Instant checkpoint #1

micromaomao · 2024-11-23T20:05:04Z

PR created for diff viewing purpose. Won't be merging.

Instead of solving a CTF challenge the way you're supposed to, this girl hacked the kernel to brute force it as fast as the code will run...

/*
 * ick: Instant checkpoint
 *
 * Provides a mechanism to "checkpoint" a process at some syscall entry, saving
 * its register and marking its writable memory pages as read-only, such that
 * any attempted writes will cause the current content of these pages to be
 * saved before allowing the write to proceed.
 *
 * At some later point in time, the process can be reverted back to the state
 * when it first made the checkpoint-ing syscall.
 *
 * To simplify the implementation, we only support single-threaded processes,
 * and we do not allow the process to make any syscalls other than read / write
 * to/from stdin/stdout/stderr. We also do not support things like huge pages.
 *
 * This is designed for quick brute-forcing of e.g. CTF binaries. A checkpoint
 * can be made when it first tries reading from stdin for a "password", and then
 * the whole process can be quickly reverted (in a matter of microseconds) to
 * try a different password if the one provided earlier was incorrect, and the
 * process tries to write a message to stdout saying so.
 */

…n_net In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the function `nfs4_state_destroy_net` in `nfs4_state_shutdown_net` will release all resources related to the hashed `nfs4_client`. If the `nfsd_client_shrinker` is running concurrently, the `expire_client` function will first unhash this client and then destroy it. This can lead to the following warning. Additionally, numerous use-after-free errors may occur as well. nfsd_client_shrinker echo 0 > /proc/fs/nfsd/threads expire_client nfsd_shutdown_net unhash_client ... nfs4_state_shutdown_net /* won't wait shrinker exit */ /* cancel_work(&nn->nfsd_shrinker_work) * nfsd_file for this /* won't destroy unhashed client1 */ * client1 still alive nfs4_state_destroy_net */ nfsd_file_cache_shutdown /* trigger warning */ kmem_cache_destroy(nfsd_file_slab) kmem_cache_destroy(nfsd_file_mark_slab) /* release nfsd_file and mark */ __destroy_client ==================================================================== BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on __kmem_cache_shutdown() -------------------------------------------------------------------- CPU: 4 UID: 0 PID: 764 Comm: sh Not tainted 6.12.0-rc3+ #1 dump_stack_lvl+0x53/0x70 slab_err+0xb0/0xf0 __kmem_cache_shutdown+0x15c/0x310 kmem_cache_destroy+0x66/0x160 nfsd_file_cache_shutdown+0xac/0x210 [nfsd] nfsd_destroy_serv+0x251/0x2a0 [nfsd] nfsd_svc+0x125/0x1e0 [nfsd] write_threads+0x16a/0x2a0 [nfsd] nfsctl_transaction_write+0x74/0xa0 [nfsd] vfs_write+0x1a5/0x6d0 ksys_write+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e ==================================================================== BUG nfsd_file_mark (Tainted: G B W ): Objects remaining nfsd_file_mark on __kmem_cache_shutdown() -------------------------------------------------------------------- dump_stack_lvl+0x53/0x70 slab_err+0xb0/0xf0 __kmem_cache_shutdown+0x15c/0x310 kmem_cache_destroy+0x66/0x160 nfsd_file_cache_shutdown+0xc8/0x210 [nfsd] nfsd_destroy_serv+0x251/0x2a0 [nfsd] nfsd_svc+0x125/0x1e0 [nfsd] write_threads+0x16a/0x2a0 [nfsd] nfsctl_transaction_write+0x74/0xa0 [nfsd] vfs_write+0x1a5/0x6d0 ksys_write+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e To resolve this issue, cancel `nfsd_shrinker_work` using synchronous mode in nfs4_state_shutdown_net. Fixes: 7c24fa2 ("NFSD: replace delayed_work with work_struct for nfsd_client_shrinker") Signed-off-by: Yang Erkun <yangerkun@huaweicloud.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

[BUG] Syzbot reports the following crash: BTRFS info (device loop0 state MCS): disabling free space tree BTRFS info (device loop0 state MCS): clearing compat-ro feature flag for FREE_SPACE_TREE (0x1) BTRFS info (device loop0 state MCS): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2) Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:backup_super_roots fs/btrfs/disk-io.c:1691 [inline] RIP: 0010:write_all_supers+0x97a/0x40f0 fs/btrfs/disk-io.c:4041 Call Trace: <TASK> btrfs_commit_transaction+0x1eae/0x3740 fs/btrfs/transaction.c:2530 btrfs_delete_free_space_tree+0x383/0x730 fs/btrfs/free-space-tree.c:1312 btrfs_start_pre_rw_mount+0xf28/0x1300 fs/btrfs/disk-io.c:3012 btrfs_remount_rw fs/btrfs/super.c:1309 [inline] btrfs_reconfigure+0xae6/0x2d40 fs/btrfs/super.c:1534 btrfs_reconfigure_for_mount fs/btrfs/super.c:2020 [inline] btrfs_get_tree_subvol fs/btrfs/super.c:2079 [inline] btrfs_get_tree+0x918/0x1920 fs/btrfs/super.c:2115 vfs_get_tree+0x90/0x2b0 fs/super.c:1800 do_new_mount+0x2be/0xb40 fs/namespace.c:3472 do_mount fs/namespace.c:3812 [inline] __do_sys_mount fs/namespace.c:4020 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f [CAUSE] To support mounting different subvolume with different RO/RW flags for the new mount APIs, btrfs introduced two workaround to support this feature: - Skip mount option/feature checks if we are mounting a different subvolume - Reconfigure the fs to RW if the initial mount is RO Combining these two, we can have the following sequence: - Mount the fs ro,rescue=all,clear_cache,space_cache=v1 rescue=all will mark the fs as hard read-only, so no v2 cache clearing will happen. - Mount a subvolume rw of the same fs. We go into btrfs_get_tree_subvol(), but fc_mount() returns EBUSY because our new fc is RW, different from the original fs. Now we enter btrfs_reconfigure_for_mount(), which switches the RO flag first so that we can grab the existing fs_info. Then we reconfigure the fs to RW. - During reconfiguration, option/features check is skipped This means we will restart the v2 cache clearing, and convert back to v1 cache. This will trigger fs writes, and since the original fs has "rescue=all" option, it skips the csum tree read. And eventually causing NULL pointer dereference in super block writeback. [FIX] For reconfiguration caused by different subvolume RO/RW flags, ensure we always run btrfs_check_options() to ensure we have proper hard RO requirements met. In fact the function btrfs_check_options() doesn't really do many complex checks, but hard RO requirement and some feature dependency checks, thus there is no special reason not to do the check for mount reconfiguration. Reported-by: syzbot+56360f93efa90ff15870@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/0000000000008c5d090621cb2770@google.com/ Fixes: f044b31 ("btrfs: handle the ro->rw transition for mounting different subvolumes") CC: stable@vger.kernel.org # 6.8+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

When creating a trace_probe we would set nr_args prior to truncating the arguments to MAX_TRACE_ARGS. However, we would only initialize arguments up to the limit. This caused invalid memory access when attempting to set up probes with more than 128 fetchargs. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 1769 Comm: cat Not tainted 6.11.0-rc7+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014 RIP: 0010:__set_print_fmt+0x134/0x330 Resolve the issue by applying the MAX_TRACE_ARGS limit earlier. Return an error when there are too many arguments instead of silently truncating. Link: https://lore.kernel.org/all/20240930202656.292869-1-mikel@mikelr.com/ Fixes: 035ba76 ("tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init") Signed-off-by: Mikel Rychliski <mikel@mikelr.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

…ing to satisfy some BPF verifiers In a RHEL8 kernel (4.18.0-513.11.1.el8_9.x86_64), that, as enterprise kernels go, have backports from modern kernels, the verifier complains about lack of bounds check for the index into the array of syscall arguments, on a BPF bytecode generated by clang 17, with: ; } else if (size < 0 && size >= -6) { /* buffer */ 116: (b7) r1 = -6 117: (2d) if r1 > r6 goto pc-30 R0=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=inv-6 R2=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3=inv(id=0) R5=inv40 R6=inv(id=0,umin_value=18446744073709551610,var_off=(0xffffffff00000000; 0xffffffff)) R7=map_value(id=0,off=56,ks=4,vs=8272,imm=0) R8=invP6 R9=map_value(id=0,off=20,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16=map_value fp-24=map_value fp-32=inv40 fp-40=ctx fp-48=map_value fp-56=inv1 fp-64=map_value fp-72=map_value fp-80=map_value ; index = -(size + 1); 118: (a7) r6 ^= -1 119: (67) r6 <<= 32 120: (77) r6 >>= 32 ; aug_size = args->args[index]; 121: (67) r6 <<= 3 122: (79) r1 = *(u64 *)(r10 -24) 123: (0f) r1 += r6 last_idx 123 first_idx 116 regs=40 stack=0 before 122: (79) r1 = *(u64 *)(r10 -24) regs=40 stack=0 before 121: (67) r6 <<= 3 regs=40 stack=0 before 120: (77) r6 >>= 32 regs=40 stack=0 before 119: (67) r6 <<= 32 regs=40 stack=0 before 118: (a7) r6 ^= -1 regs=40 stack=0 before 117: (2d) if r1 > r6 goto pc-30 regs=42 stack=0 before 116: (b7) r1 = -6 R0_w=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=inv1 R2_w=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3_w=inv(id=0) R5_w=inv40 R6_rw=invP(id=0,smin_value=-2147483648,smax_value=0) R7_w=map_value(id=0,off=56,ks=4,vs=8272,imm=0) R8_w=invP6 R9_w=map_value(id=0,off=20,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16_w=map_value fp-24_r=map_value fp-32_w=inv40 fp-40=ctx fp-48=map_value fp-56_w=inv1 fp-64_w=map_value fp-72=map_value fp-80=map_value parent didn't have regs=40 stack=0 marks last_idx 110 first_idx 98 regs=40 stack=0 before 110: (6d) if r1 s> r6 goto pc+5 regs=42 stack=0 before 109: (b7) r1 = 1 regs=40 stack=0 before 108: (65) if r6 s> 0x1000 goto pc+7 regs=40 stack=0 before 98: (55) if r6 != 0x1 goto pc+9 R0_w=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=invP12 R2_w=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3_rw=inv(id=0) R5_w=inv24 R6_rw=invP(id=0,smin_value=-2147483648,smax_value=2147483647) R7_w=map_value(id=0,off=40,ks=4,vs=8272,imm=0) R8_rw=invP4 R9_w=map_value(id=0,off=12,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16_rw=map_value fp-24_r=map_value fp-32_rw=invP24 fp-40_r=ctx fp-48_r=map_value fp-56_w=invP1 fp-64_rw=map_value fp-72_r=map_value fp-80_r=map_value parent already had regs=40 stack=0 marks 124: (79) r6 = *(u64 *)(r1 +16) R0=map_value(id=0,off=0,ks=4,vs=24688,imm=0) R1_w=map_value(id=0,off=0,ks=4,vs=8272,umax_value=34359738360,var_off=(0x0; 0x7fffffff8),s32_max_value=2147483640,u32_max_value=-8) R2=map_value(id=0,off=16,ks=4,vs=8272,imm=0) R3=inv(id=0) R5=inv40 R6_w=invP(id=0,umax_value=34359738360,var_off=(0x0; 0x7fffffff8),s32_max_value=2147483640,u32_max_value=-8) R7=map_value(id=0,off=56,ks=4,vs=8272,imm=0) R8=invP6 R9=map_value(id=0,off=20,ks=4,vs=24,imm=0) R10=fp0 fp-8=mmmmmmmm fp-16=map_value fp-24=map_value fp-32=inv40 fp-40=ctx fp-48=map_value fp-56=inv1 fp-64=map_value fp-72=map_value fp-80=map_value R1 unbounded memory access, make sure to bounds check any such access processed 466 insns (limit 1000000) max_states_per_insn 2 total_states 20 peak_states 20 mark_read 3 If we add this line, as used in other BPF programs, to cap that index: index &= 7; The generated BPF program is considered safe by that version of the BPF verifier, allowing perf to collect the syscall args in one more kernel using the BPF based pointer contents collector. With the above one-liner it works with that kernel: [root@dell-per740-01 ~]# uname -a Linux dell-per740-01.khw.eng.rdu2.dc.redhat.com 4.18.0-513.11.1.el8_9.x86_64 #1 SMP Thu Dec 7 03:06:13 EST 2023 x86_64 x86_64 x86_64 GNU/Linux [root@dell-per740-01 ~]# ~acme/bin/perf trace -e *sleep* sleep 1.234567890 0.000 (1234.704 ms): sleep/3863610 nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 234567890 }) = 0 [root@dell-per740-01 ~]# As well as with the one in Fedora 40: root@number:~# uname -a Linux number 6.11.3-200.fc40.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Oct 10 22:31:19 UTC 2024 x86_64 GNU/Linux root@number:~# perf trace -e *sleep* sleep 1.234567890 0.000 (1234.722 ms): sleep/14873 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 234567890 }, rmtp: 0x7ffe87311a40) = 0 root@number:~# Song Liu reported that this one-liner was being optimized out by clang 18, so I suggested and he tested that adding a compiler barrier before it made clang v18 to keep it and the verifier in the kernel in Song's case (Meta's 5.12 based kernel) also was happy with the resulting bytecode. I'll investigate using virtme-ng[1] to have all the perf BPF based functionality thoroughly tested over multiple kernels and clang versions. [1] https://kernel-recipes.org/en/2024/virtme-ng/ Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alan Maguire <alan.maguire@oracle.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrea Righi <andrea.righi@linux.dev> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/lkml/Zw7JgJc0LOwSpuvx@x1 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The purpose of btrfs_bbio_propagate_error() shall be propagating an error of split bio to its original btrfs_bio, and tell the error to the upper layer. However, it's not working well on some cases. * Case 1. Immediate (or quick) end_bio with an error When btrfs sends btrfs_bio to mirrored devices, btrfs calls btrfs_bio_end_io() when all the mirroring bios are completed. If that btrfs_bio was split, it is from btrfs_clone_bioset and its end_io function is btrfs_orig_write_end_io. For this case, btrfs_bbio_propagate_error() accesses the orig_bbio's bio context to increase the error count. That works well in most cases. However, if the end_io is called enough fast, orig_bbio's (remaining part after split) bio context may not be properly set at that time. Since the bio context is set when the orig_bbio (the last btrfs_bio) is sent to devices, that might be too late for earlier split btrfs_bio's completion. That will result in NULL pointer dereference. That bug is easily reproducible by running btrfs/146 on zoned devices [1] and it shows the following trace. [1] You need raid-stripe-tree feature as it create "-d raid0 -m raid1" FS. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 Not tainted 6.11.0-rc7-BTRFS-ZNS+ torvalds#474 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: writeback wb_workfn (flush-btrfs-5) RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs] BTRFS error (device dm-0): bdev /dev/mapper/error-test errs: wr 2, rd 0, flush 0, corrupt 0, gen 0 RSP: 0018:ffffc9000006f248 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080 RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58 R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158 FS: 0000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __die_body.cold+0x19/0x26 ? page_fault_oops+0x13e/0x2b0 ? _printk+0x58/0x73 ? do_user_addr_fault+0x5f/0x750 ? exc_page_fault+0x76/0x240 ? asm_exc_page_fault+0x22/0x30 ? btrfs_bio_end_io+0xae/0xc0 [btrfs] ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs] btrfs_orig_write_end_io+0x51/0x90 [btrfs] dm_submit_bio+0x5c2/0xa50 [dm_mod] ? find_held_lock+0x2b/0x80 ? blk_try_enter_queue+0x90/0x1e0 __submit_bio+0xe0/0x130 ? ktime_get+0x10a/0x160 ? lockdep_hardirqs_on+0x74/0x100 submit_bio_noacct_nocheck+0x199/0x410 btrfs_submit_bio+0x7d/0x150 [btrfs] btrfs_submit_chunk+0x1a1/0x6d0 [btrfs] ? lockdep_hardirqs_on+0x74/0x100 ? __folio_start_writeback+0x10/0x2c0 btrfs_submit_bbio+0x1c/0x40 [btrfs] submit_one_bio+0x44/0x60 [btrfs] submit_extent_folio+0x13f/0x330 [btrfs] ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs] extent_writepage_io+0x18b/0x360 [btrfs] extent_write_locked_range+0x17c/0x340 [btrfs] ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs] run_delalloc_cow+0x71/0xd0 [btrfs] btrfs_run_delalloc_range+0x176/0x500 [btrfs] ? find_lock_delalloc_range+0x119/0x260 [btrfs] writepage_delalloc+0x2ab/0x480 [btrfs] extent_write_cache_pages+0x236/0x7d0 [btrfs] btrfs_writepages+0x72/0x130 [btrfs] do_writepages+0xd4/0x240 ? find_held_lock+0x2b/0x80 ? wbc_attach_and_unlock_inode+0x12c/0x290 ? wbc_attach_and_unlock_inode+0x12c/0x290 __writeback_single_inode+0x5c/0x4c0 ? do_raw_spin_unlock+0x49/0xb0 writeback_sb_inodes+0x22c/0x560 __writeback_inodes_wb+0x4c/0xe0 wb_writeback+0x1d6/0x3f0 wb_workfn+0x334/0x520 process_one_work+0x1ee/0x570 ? lock_is_held_type+0xc6/0x130 worker_thread+0x1d1/0x3b0 ? __pfx_worker_thread+0x10/0x10 kthread+0xee/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Modules linked in: dm_mod btrfs blake2b_generic xor raid6_pq rapl CR2: 0000000000000020 * Case 2. Earlier completion of orig_bbio for mirrored btrfs_bios btrfs_bbio_propagate_error() assumes the end_io function for orig_bbio is called last among split bios. In that case, btrfs_orig_write_end_io() sets the bio->bi_status to BLK_STS_IOERR by seeing the bioc->error [2]. Otherwise, the increased orig_bio's bioc->error is not checked by anyone and return BLK_STS_OK to the upper layer. [2] Actually, this is not true. Because we only increases orig_bioc->errors by max_errors, the condition "atomic_read(&bioc->error) > bioc->max_errors" is still not met if only one split btrfs_bio fails. * Case 3. Later completion of orig_bbio for un-mirrored btrfs_bios In contrast to the above case, btrfs_bbio_propagate_error() is not working well if un-mirrored orig_bbio is completed last. It sets orig_bbio->bio.bi_status to the btrfs_bio's error. But, that is easily over-written by orig_bbio's completion status. If the status is BLK_STS_OK, the upper layer would not know the failure. * Solution Considering the above cases, we can only save the error status in the orig_bbio (remaining part after split) itself as it is always available. Also, the saved error status should be propagated when all the split btrfs_bios are finished (i.e, bbio->pending_ios == 0). This commit introduces "status" to btrfs_bbio and saves the first error of split bios to original btrfs_bio's "status" variable. When all the split bios are finished, the saved status is loaded into original btrfs_bio's status. With this commit, btrfs/146 on zoned devices does not hit the NULL pointer dereference anymore. Fixes: 852eee6 ("btrfs: allow btrfs_submit_bio to split bios") CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>

Running rcutorture scenario TREE05, the below warning is triggered. [ 32.604594] WARNING: suspicious RCU usage [ 32.605928] 6.11.0-rc5-00040-g4ba4f1afb6a9 #55238 Not tainted [ 32.607812] ----------------------------- [ 32.609140] kernel/events/core.c:13946 RCU-list traversed in non-reader section!! [ 32.611595] other info that might help us debug this: [ 32.614247] rcu_scheduler_active = 2, debug_locks = 1 [ 32.616392] 3 locks held by cpuhp/4/35: [ 32.617687] #0: ffffffffb666a650 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.620563] #1: ffffffffb666cd20 (cpuhp_state-down){+.+.}-{0:0}, at: cpuhp_thread_fun+0x4e/0x200 [ 32.623412] #2: ffffffffb677c288 (pmus_lock){+.+.}-{3:3}, at: perf_event_exit_cpu_context+0x32/0x2f0 In perf_event_clear_cpumask(), uses list_for_each_entry_rcu() without an obvious RCU read-side critical section. Either pmus_srcu or pmus_lock is good enough to protect the pmus list. In the current context, pmus_lock is already held. The list_for_each_entry_rcu() is not required. Fixes: 4ba4f1a ("perf: Generic hotplug support for a PMU with a scope") Closes: https://lore.kernel.org/lkml/2b66dff8-b827-494b-b151-1ad8d56f13e6@paulmck-laptop/ Closes: https://lore.kernel.org/oe-lkp/202409131559.545634cc-oliver.sang@intel.com Reported-by: "Paul E. McKenney" <paulmck@kernel.org> Reported-by: kernel test robot <oliver.sang@intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: "Paul E. McKenney" <paulmck@kernel.org> Link: https://lore.kernel.org/r/20240913162340.2142976-1-kan.liang@linux.intel.com

Add check for the return value of spi_get_csgpiod() to avoid passing a NULL pointer to gpiod_direction_output(), preventing a crash when GPIO chip select is not used. Fix below crash: [ 4.251960] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 4.260762] Mem abort info: [ 4.263556] ESR = 0x0000000096000004 [ 4.267308] EC = 0x25: DABT (current EL), IL = 32 bits [ 4.272624] SET = 0, FnV = 0 [ 4.275681] EA = 0, S1PTW = 0 [ 4.278822] FSC = 0x04: level 0 translation fault [ 4.283704] Data abort info: [ 4.286583] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 4.292074] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 4.297130] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 4.302445] [0000000000000000] user address but active_mm is swapper [ 4.308805] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 4.315072] Modules linked in: [ 4.318124] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc4-next-20241023-00008-ga20ec42c5fc1 torvalds#359 [ 4.328130] Hardware name: LS1046A QDS Board (DT) [ 4.332832] pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 4.339794] pc : gpiod_direction_output+0x34/0x5c [ 4.344505] lr : gpiod_direction_output+0x18/0x5c [ 4.349208] sp : ffff80008003b8f0 [ 4.352517] x29: ffff80008003b8f0 x28: 0000000000000000 x27: ffffc96bcc7e9068 [ 4.359659] x26: ffffc96bcc6e00b0 x25: ffffc96bcc598398 x24: ffff447400132810 [ 4.366800] x23: 0000000000000000 x22: 0000000011e1a300 x21: 0000000000020002 [ 4.373940] x20: 0000000000000000 x19: 0000000000000000 x18: ffffffffffffffff [ 4.381081] x17: ffff44740016e600 x16: 0000000500000003 x15: 0000000000000007 [ 4.388221] x14: 0000000000989680 x13: 0000000000020000 x12: 000000000000001e [ 4.395362] x11: 0044b82fa09b5a53 x10: 0000000000000019 x9 : 0000000000000008 [ 4.402502] x8 : 0000000000000002 x7 : 0000000000000007 x6 : 0000000000000000 [ 4.409641] x5 : 0000000000000200 x4 : 0000000002000000 x3 : 0000000000000000 [ 4.416781] x2 : 0000000000022202 x1 : 0000000000000000 x0 : 0000000000000000 [ 4.423921] Call trace: [ 4.426362] gpiod_direction_output+0x34/0x5c (P) [ 4.431067] gpiod_direction_output+0x18/0x5c (L) [ 4.435771] dspi_setup+0x220/0x334 Fixes: 9e264f3 ("spi: Replace all spi->chip_select and spi->cs_gpiod references with function call") Cc: stable@vger.kernel.org Signed-off-by: Frank Li <Frank.Li@nxp.com> Link: https://patch.msgid.link/20241023203032.1388491-1-Frank.Li@nxp.com Signed-off-by: Mark Brown <broonie@kernel.org>

… non-PCI device The function cxl_endpoint_gather_bandwidth() invokes pci_bus_read/write_XXX(), however, not all CXL devices are presently implemented via PCI. It is recognized that the cxl_test has realized a CXL device using a platform device. Calling pci_bus_read/write_XXX() in cxl_test will cause kernel panic: platform cxl_host_bridge.3: host supports CXL (restricted) Oops: general protection fault, probably for non-canonical address 0x3ef17856fcae4fbd: 0000 [#1] PREEMPT SMP PTI Call Trace: <TASK> ? __die_body.cold+0x19/0x27 ? die_addr+0x38/0x60 ? exc_general_protection+0x1f5/0x4b0 ? asm_exc_general_protection+0x22/0x30 ? pci_bus_read_config_word+0x1c/0x60 pcie_capability_read_word+0x93/0xb0 pcie_link_speed_mbps+0x18/0x50 cxl_pci_get_bandwidth+0x18/0x60 [cxl_core] cxl_endpoint_gather_bandwidth.constprop.0+0xf4/0x230 [cxl_core] ? xas_store+0x54/0x660 ? preempt_count_add+0x69/0xa0 ? _raw_spin_lock+0x13/0x40 ? __kmalloc_cache_noprof+0xe7/0x270 cxl_region_shared_upstream_bandwidth_update+0x9c/0x790 [cxl_core] cxl_region_attach+0x520/0x7e0 [cxl_core] store_targetN+0xf2/0x120 [cxl_core] kernfs_fop_write_iter+0x13a/0x1f0 vfs_write+0x23b/0x410 ksys_write+0x53/0xd0 do_syscall_64+0x62/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e And Ying also reported a KASAN error with similar calltrace. Reported-by: Huang, Ying <ying.huang@intel.com> Closes: http://lore.kernel.org/87y12w9vp5.fsf@yhuang6-desk2.ccr.corp.intel.com Fixes: a5ab0de ("cxl: Calculate region bandwidth of targets with shared upstream link") Signed-off-by: Li Zhijian <lizhijian@fujitsu.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Huang, Ying <ying.huang@intel.com> Link: https://patch.msgid.link/20241022030054.258942-1-lizhijian@fujitsu.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>

In support of investigating an initialization failure report [1], cxl_test was updated to register mock memory-devices after the mock root-port/bus device had been registered. That led to cxl_test crashing with a use-after-free bug with the following signature: cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1 cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1 cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0 1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1 [..] cxld_unregister: cxl decoder14.0: cxl_region_decode_reset: cxl_region region3: mock_decoder_reset: cxl_port port3: decoder3.0 reset 2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1 cxl_endpoint_decoder_release: cxl decoder14.0: [..] cxld_unregister: cxl decoder7.0: 3) cxl_region_decode_reset: cxl_region region3: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI [..] RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core] [..] Call Trace: <TASK> cxl_region_decode_reset+0x69/0x190 [cxl_core] cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x5d/0x60 [cxl_core] At 1) a region has been established with 2 endpoint decoders (7.0 and 14.0). Those endpoints share a common switch-decoder in the topology (3.0). At teardown, 2), decoder14.0 is the first to be removed and hits the "out of order reset case" in the switch decoder. The effect though is that region3 cleanup is aborted leaving it in-tact and referencing decoder14.0. At 3) the second attempt to teardown region3 trips over the stale decoder14.0 object which has long since been deleted. The fix here is to recognize that the CXL specification places no mandate on in-order shutdown of switch-decoders, the driver enforces in-order allocation, and hardware enforces in-order commit. So, rather than fail and leave objects dangling, always remove them. In support of making cxl_region_decode_reset() always succeed, cxl_region_invalidate_memregion() failures are turned into warnings. Crashing the kernel is ok there since system integrity is at risk if caches cannot be managed around physical address mutation events like CXL region destruction. A new device_for_each_child_reverse_from() is added to cleanup port->commit_end after all dependent decoders have been disabled. In other words if decoders are allocated 0->1->2 and disabled 1->2->0 then port->commit_end only decrements from 2 after 2 has been disabled, and it decrements all the way to zero since 1 was disabled previously. Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Cc: stable@vger.kernel.org Fixes: 176baef ("cxl/hdm: Commit decoder state to hardware") Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Zijun Hu <quic_zijuhu@quicinc.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Under memory pressure it's possible for GFP_ATOMIC order-0 allocations to fail even though free pages are available in the highatomic reserves. GFP_ATOMIC allocations cannot trigger unreserve_highatomic_pageblock() since it's only run from reclaim. Given that such allocations will pass the watermarks in __zone_watermark_unusable_free(), it makes sense to fallback to highatomic reserves the same way that ALLOC_OOM can. This fixes order-0 page allocation failures observed on Cloudflare's fleet when handling network packets: kswapd1: page allocation failure: order:0, mode:0x820(GFP_ATOMIC), nodemask=(null),cpuset=/,mems_allowed=0-7 CPU: 10 PID: 696 Comm: kswapd1 Kdump: loaded Tainted: G O 6.6.43-CUSTOM #1 Hardware name: MACHINE Call Trace: <IRQ> dump_stack_lvl+0x3c/0x50 warn_alloc+0x13a/0x1c0 __alloc_pages_slowpath.constprop.0+0xc9d/0xd10 __alloc_pages+0x327/0x340 __napi_alloc_skb+0x16d/0x1f0 bnxt_rx_page_skb+0x96/0x1b0 [bnxt_en] bnxt_rx_pkt+0x201/0x15e0 [bnxt_en] __bnxt_poll_work+0x156/0x2b0 [bnxt_en] bnxt_poll+0xd9/0x1c0 [bnxt_en] __napi_poll+0x2b/0x1b0 bpf_trampoline_6442524138+0x7d/0x1000 __napi_poll+0x5/0x1b0 net_rx_action+0x342/0x740 handle_softirqs+0xcf/0x2b0 irq_exit_rcu+0x6c/0x90 sysvec_apic_timer_interrupt+0x72/0x90 </IRQ> [mfleming@cloudflare.com: update comment] Link: https://lkml.kernel.org/r/20241015125158.3597702-1-matt@readmodwrite.com Link: https://lkml.kernel.org/r/20241011120737.3300370-1-matt@readmodwrite.com Link: https://lore.kernel.org/all/CAGis_TWzSu=P7QJmjD58WWiu3zjMTVKSzdOwWE8ORaGytzWJwQ@mail.gmail.com/ Fixes: 1d91df8 ("mm/page_alloc: handle a missing case for memalloc_nocma_{save/restore} APIs") Signed-off-by: Matt Fleming <mfleming@cloudflare.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

walk_system_ram_res_rev() erroneously discards resource flags when passing the information to the callback. This causes systems with IORESOURCE_SYSRAM_DRIVER_MANAGED memory to have these resources selected during kexec to store kexec buffers if that memory happens to be at placed above normal system ram. This leads to undefined behavior after reboot. If the kexec buffer is never touched, nothing happens. If the kexec buffer is touched, it could lead to a crash (like below) or undefined behavior. Tested on a system with CXL memory expanders with driver managed memory, TPM enabled, and CONFIG_IMA_KEXEC=y. Adding printk's showed the flags were being discarded and as a result the check for IORESOURCE_SYSRAM_DRIVER_MANAGED passes. find_next_iomem_res: name(System RAM (kmem)) start(10000000000) end(1034fffffff) flags(83000200) locate_mem_hole_top_down: start(10000000000) end(1034fffffff) flags(0) [.] BUG: unable to handle page fault for address: ffff89834ffff000 [.] #PF: supervisor read access in kernel mode [.] #PF: error_code(0x0000) - not-present page [.] PGD c04c8bf067 P4D c04c8bf067 PUD c04c8be067 PMD 0 [.] Oops: 0000 [#1] SMP [.] RIP: 0010:ima_restore_measurement_list+0x95/0x4b0 [.] RSP: 0018:ffffc900000d3a80 EFLAGS: 00010286 [.] RAX: 0000000000001000 RBX: 0000000000000000 RCX: ffff89834ffff000 [.] RDX: 0000000000000018 RSI: ffff89834ffff000 RDI: ffff89834ffff018 [.] RBP: ffffc900000d3ba0 R08: 0000000000000020 R09: ffff888132b8a900 [.] R10: 4000000000000000 R11: 000000003a616d69 R12: 0000000000000000 [.] R13: ffffffff8404ac28 R14: 0000000000000000 R15: ffff89834ffff000 [.] FS: 0000000000000000(0000) GS:ffff893d44640000(0000) knlGS:0000000000000000 [.] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [.] ata5: SATA link down (SStatus 0 SControl 300) [.] CR2: ffff89834ffff000 CR3: 000001034d00f001 CR4: 0000000000770ef0 [.] PKRU: 55555554 [.] Call Trace: [.] <TASK> [.] ? __die+0x78/0xc0 [.] ? page_fault_oops+0x2a8/0x3a0 [.] ? exc_page_fault+0x84/0x130 [.] ? asm_exc_page_fault+0x22/0x30 [.] ? ima_restore_measurement_list+0x95/0x4b0 [.] ? template_desc_init_fields+0x317/0x410 [.] ? crypto_alloc_tfm_node+0x9c/0xc0 [.] ? init_ima_lsm+0x30/0x30 [.] ima_load_kexec_buffer+0x72/0xa0 [.] ima_init+0x44/0xa0 [.] __initstub__kmod_ima__373_1201_init_ima7+0x1e/0xb0 [.] ? init_ima_lsm+0x30/0x30 [.] do_one_initcall+0xad/0x200 [.] ? idr_alloc_cyclic+0xaa/0x110 [.] ? new_slab+0x12c/0x420 [.] ? new_slab+0x12c/0x420 [.] ? number+0x12a/0x430 [.] ? sysvec_apic_timer_interrupt+0xa/0x80 [.] ? asm_sysvec_apic_timer_interrupt+0x16/0x20 [.] ? parse_args+0xd4/0x380 [.] ? parse_args+0x14b/0x380 [.] kernel_init_freeable+0x1c1/0x2b0 [.] ? rest_init+0xb0/0xb0 [.] kernel_init+0x16/0x1a0 [.] ret_from_fork+0x2f/0x40 [.] ? rest_init+0xb0/0xb0 [.] ret_from_fork_asm+0x11/0x20 [.] </TASK> Link: https://lore.kernel.org/all/20231114091658.228030-1-bhe@redhat.com/ Link: https://lkml.kernel.org/r/20241017190347.5578-1-gourry@gourry.net Fixes: 7acf164 ("resource: add walk_system_ram_res_rev()") Signed-off-by: Gregory Price <gourry@gourry.net> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The following BUG was triggered: ============================= [ BUG: Invalid wait context ] 6.12.0-rc2-XXX torvalds#406 Not tainted ----------------------------- kworker/1:1/62 is trying to lock: ffffff8801593030 (&cpc_ptr->rmw_lock){+.+.}-{3:3}, at: cpc_write+0xcc/0x370 other info that might help us debug this: context-{5:5} 2 locks held by kworker/1:1/62: #0: ffffff897ef5ec98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x50 #1: ffffff880154e238 (&sg_policy->update_lock){....}-{2:2}, at: sugov_update_shared+0x3c/0x280 stack backtrace: CPU: 1 UID: 0 PID: 62 Comm: kworker/1:1 Not tainted 6.12.0-rc2-g9654bd3e8806 torvalds#406 Workqueue: 0x0 (events) Call trace: dump_backtrace+0xa4/0x130 show_stack+0x20/0x38 dump_stack_lvl+0x90/0xd0 dump_stack+0x18/0x28 __lock_acquire+0x480/0x1ad8 lock_acquire+0x114/0x310 _raw_spin_lock+0x50/0x70 cpc_write+0xcc/0x370 cppc_set_perf+0xa0/0x3a8 cppc_cpufreq_fast_switch+0x40/0xc0 cpufreq_driver_fast_switch+0x4c/0x218 sugov_update_shared+0x234/0x280 update_load_avg+0x6ec/0x7b8 dequeue_entities+0x108/0x830 dequeue_task_fair+0x58/0x408 __schedule+0x4f0/0x1070 schedule+0x54/0x130 worker_thread+0xc0/0x2e8 kthread+0x130/0x148 ret_from_fork+0x10/0x20 sugov_update_shared() locks a raw_spinlock while cpc_write() locks a spinlock. To have a correct wait-type order, update rmw_lock to a raw spinlock and ensure that interrupts will be disabled on the CPU holding it. Fixes: 60949b7 ("ACPI: CPPC: Fix MASK_VAL() usage") Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Link: https://patch.msgid.link/20241028125657.1271512-1-pierre.gondois@arm.com [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

I got a syzbot report without a repro [1] crashing in nf_send_reset6() I think the issue is that dev->hard_header_len is zero, and we attempt later to push an Ethernet header. Use LL_MAX_HEADER, as other functions in net/ipv6/netfilter/nf_reject_ipv6.c. [1] skbuff: skb_under_panic: text:ffffffff89b1d008 len:74 put:14 head:ffff88803123aa00 data:ffff88803123a9f2 tail:0x3c end:0x140 dev:syz_tun kernel BUG at net/core/skbuff.c:206 ! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 UID: 0 PID: 7373 Comm: syz.1.568 Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline] RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216 Code: 0d 8d 48 c7 c6 60 a6 29 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 ba 30 38 02 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 RSP: 0018:ffffc900045269b0 EFLAGS: 00010282 RAX: 0000000000000088 RBX: dffffc0000000000 RCX: cd66dacdc5d8e800 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000000 RBP: ffff88802d39a3d0 R08: ffffffff8174afec R09: 1ffff920008a4ccc R10: dffffc0000000000 R11: fffff520008a4ccd R12: 0000000000000140 R13: ffff88803123aa00 R14: ffff88803123a9f2 R15: 000000000000003c FS: 00007fdbee5ff6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000005d322000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> skb_push+0xe5/0x100 net/core/skbuff.c:2636 eth_header+0x38/0x1f0 net/ethernet/eth.c:83 dev_hard_header include/linux/netdevice.h:3208 [inline] nf_send_reset6+0xce6/0x1270 net/ipv6/netfilter/nf_reject_ipv6.c:358 nft_reject_inet_eval+0x3b9/0x690 net/netfilter/nft_reject_inet.c:48 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_pre_routing_ipv6+0x63e/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x13e8/0x4570 net/core/dev.c:5562 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5781 netif_receive_skb_internal net/core/dev.c:5867 [inline] netif_receive_skb+0x1e8/0x890 net/core/dev.c:5926 tun_rx_batched+0x1b7/0x8f0 drivers/net/tun.c:1550 tun_get_user+0x3056/0x47e0 drivers/net/tun.c:2007 tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2053 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6d/0xc90 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdbeeb7d1ff Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 c9 8d 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 1c 8e 02 00 48 RSP: 002b:00007fdbee5ff000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fdbeed36058 RCX: 00007fdbeeb7d1ff RDX: 000000000000008e RSI: 0000000020000040 RDI: 00000000000000c8 RBP: 00007fdbeebf12be R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000008e R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdbeed36058 R15: 00007ffc38de06e8 </TASK> Fixes: c8d7b98 ("netfilter: move nf_send_resetX() code to nf_reject_ipvX modules") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Hou Tao says: ==================== The patch set fixes several issues in bits iterator. Patch #1 fixes the kmemleak problem of bits iterator. Patch #2~#3 fix the overflow problem of nr_bits. Patch #4 fixes the potential stack corruption when bits iterator is used on 32-bit host. Patch #5 adds more test cases for bits iterator. Please see the individual patches for more details. And comments are always welcome. --- v4: * patch #1: add ack from Yafang * patch #3: revert code-churn like changes: (1) compute nr_bytes and nr_bits before the check of nr_words. (2) use nr_bits == 64 to check for single u64, preventing build warning on 32-bit hosts. * patch #4: use "BITS_PER_LONG == 32" instead of "!defined(CONFIG_64BIT)" v3: https://lore.kernel.org/bpf/20241025013233.804027-1-houtao@huaweicloud.com/T/#t * split the bits-iterator related patches from "Misc fixes for bpf" patch set * patch #1: use "!nr_bits || bits >= nr_bits" to stop the iteration * patch #2: add a new helper for the overflow problem * patch #3: decrease the limitation from 512 to 511 and check whether nr_bytes is too large for bpf memory allocator explicitly * patch #5: add two more test cases for bit iterator v2: http://lore.kernel.org/bpf/d49fa2f4-f743-c763-7579-c3cab4dd88cb@huaweicloud.com ==================== Link: https://lore.kernel.org/r/20241030100516.3633640-1-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Petr Machata says: ==================== mlxsw: Fixes In this patchset: - Tx header should be pushed for each packet which is transmitted via Spectrum ASICs. Patch #1 adds a missing call to skb_cow_head() to make sure that there is both enough room to push the Tx header and that the SKB header is not cloned and can be modified. - Commit b5b60bb ("mlxsw: pci: Use page pool for Rx buffers allocation") converted mlxsw to use page pool for Rx buffers allocation. Sync for CPU and for device should be done for Rx pages. In patches #2 and #3, add the missing calls to sync pages for, respectively, CPU and the device. - Patch #4 then fixes a bug to IPv6 GRE forwarding offload. Patch #5 adds a generic forwarding test that fails with mlxsw ports prior to the fix. ==================== Link: https://patch.msgid.link/cover.1729866134.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

When we compile and load lib/slub_kunit.c,it will cause a panic. The root cause is that __kmalloc_cache_noprof was directly called instead of kmem_cache_alloc,which resulted in no alloc_tag being allocated.This caused current->alloc_tag to be null,leading to a null pointer dereference in alloc_tag_ref_set. Despite the fact that my colleague Pei Xiao will later fix the code in slub_kunit.c,we still need fix null pointer check logic for ref and tag to avoid panic caused by a null pointer dereference. Here is the log for the panic: [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020 [ 74.780130][ T2158] Mem abort info: [ 74.780406][ T2158] ESR = 0x0000000096000004 [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits [ 74.781225][ T2158] SET = 0, FnV = 0 [ 74.781529][ T2158] EA = 0, S1PTW = 0 [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault [ 74.782288][ T2158] Data abort info: [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000 [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000 [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4 [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2 [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.794095][ T2158] sp : ffff800084d33cd0 [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000 [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314 [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088 [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00 [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537 [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0 [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001 [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000 [ 74.801656][ T2158] Call trace: [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit] [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit] [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit] [ 74.804768][ T2158] kthread+0x10c/0x118 [ 74.805141][ T2158] ret_from_fork+0x10/0x20 [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3) [ 74.806176][ T2158] SMP: stopping secondary CPUs [ 74.808130][ T2158] Starting crashdump kernel... Link: https://lkml.kernel.org/r/20241020070819.307944-1-hao.ge@linux.dev Fixes: e0a955b ("mm/codetag: add pgalloc_tag_copy()") Signed-off-by: Hao Ge <gehao@kylinos.cn> Acked-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Yu Zhao <yuzhao@google.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Enqueue packets in dql after dma engine starts causes race condition. Tx transfer starts once dma engine is started and may execute dql dequeue in completion before it gets queued. It results in following kernel crash while running iperf stress test: kernel BUG at lib/dynamic_queue_limits.c:99! <snip> Internal error: Oops - BUG: 00000000f2000800 [#1] SMP pc : dql_completed+0x238/0x248 lr : dql_completed+0x3c/0x248 Call trace: dql_completed+0x238/0x248 axienet_dma_tx_cb+0xa0/0x170 xilinx_dma_do_tasklet+0xdc/0x290 tasklet_action_common+0xf8/0x11c tasklet_action+0x30/0x3c handle_softirqs+0xf8/0x230 <snip> Start dmaengine after enqueue in dql fixes the crash. Fixes: 6a91b84 ("net: axienet: Introduce dmaengine support") Signed-off-by: Suraj Gupta <suraj.gupta2@amd.com> Link: https://patch.msgid.link/20241030062533.2527042-2-suraj.gupta2@amd.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Recently, we got a customer report that CIFS triggers oops while reconnecting to a server. [0] The workload runs on Kubernetes, and some pods mount CIFS servers in non-root network namespaces. The problem rarely happened, but it was always while the pod was dying. The root cause is wrong reference counting for network namespace. CIFS uses kernel sockets, which do not hold refcnt of the netns that the socket belongs to. That means CIFS must ensure the socket is always freed before its netns; otherwise, use-after-free happens. The repro steps are roughly: 1. mount CIFS in a non-root netns 2. drop packets from the netns 3. destroy the netns 4. unmount CIFS We can reproduce the issue quickly with the script [1] below and see the splat [2] if CONFIG_NET_NS_REFCNT_TRACKER is enabled. When the socket is TCP, it is hard to guarantee the netns lifetime without holding refcnt due to async timers. Let's hold netns refcnt for each socket as done for SMC in commit 9744d2b ("smc: Fix use-after-free in tcp_write_timer_handler()."). Note that we need to move put_net() from cifs_put_tcp_session() to clean_demultiplex_info(); otherwise, __sock_create() still could touch a freed netns while cifsd tries to reconnect from cifs_demultiplex_thread(). Also, maybe_get_net() cannot be put just before __sock_create() because the code is not under RCU and there is a small chance that the same address happened to be reallocated to another netns. [0]: CIFS: VFS: \\XXXXXXXXXXX has not responded in 15 seconds. Reconnecting... CIFS: Serverclose failed 4 times, giving up Unable to handle kernel paging request at virtual address 14de99e461f84a07 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [14de99e461f84a07] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: cls_bpf sch_ingress nls_utf8 cifs cifs_arc4 cifs_md4 dns_resolver tcp_diag inet_diag veth xt_state xt_connmark nf_conntrack_netlink xt_nat xt_statistic xt_MASQUERADE xt_mark xt_addrtype ipt_REJECT nf_reject_ipv4 nft_chain_nat nf_nat xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_comment nft_compat nf_tables nfnetlink overlay nls_ascii nls_cp437 sunrpc vfat fat aes_ce_blk aes_ce_cipher ghash_ce sm4_ce_cipher sm4 sm3_ce sm3 sha3_ce sha512_ce sha512_arm64 sha1_ce ena button sch_fq_codel loop fuse configfs dmi_sysfs sha2_ce sha256_arm64 dm_mirror dm_region_hash dm_log dm_mod dax efivarfs CPU: 5 PID: 2690970 Comm: cifsd Not tainted 6.1.103-109.184.amzn2023.aarch64 #1 Hardware name: Amazon EC2 r7g.4xlarge/, BIOS 1.0 11/1/2018 pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : fib_rules_lookup+0x44/0x238 lr : __fib_lookup+0x64/0xbc sp : ffff8000265db790 x29: ffff8000265db790 x28: 0000000000000000 x27: 000000000000bd01 x26: 0000000000000000 x25: ffff000b4baf8000 x24: ffff00047b5e4580 x23: ffff8000265db7e0 x22: 0000000000000000 x21: ffff00047b5e4500 x20: ffff0010e3f694f8 x19: 14de99e461f849f7 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 3f92800abd010002 x11: 0000000000000001 x10: ffff0010e3f69420 x9 : ffff800008a6f294 x8 : 0000000000000000 x7 : 0000000000000006 x6 : 0000000000000000 x5 : 0000000000000001 x4 : ffff001924354280 x3 : ffff8000265db7e0 x2 : 0000000000000000 x1 : ffff0010e3f694f8 x0 : ffff00047b5e4500 Call trace: fib_rules_lookup+0x44/0x238 __fib_lookup+0x64/0xbc ip_route_output_key_hash_rcu+0x2c4/0x398 ip_route_output_key_hash+0x60/0x8c tcp_v4_connect+0x290/0x488 __inet_stream_connect+0x108/0x3d0 inet_stream_connect+0x50/0x78 kernel_connect+0x6c/0xac generic_ip_connect+0x10c/0x6c8 [cifs] __reconnect_target_unlocked+0xa0/0x214 [cifs] reconnect_dfs_server+0x144/0x460 [cifs] cifs_reconnect+0x88/0x148 [cifs] cifs_readv_from_socket+0x230/0x430 [cifs] cifs_read_from_socket+0x74/0xa8 [cifs] cifs_demultiplex_thread+0xf8/0x704 [cifs] kthread+0xd0/0xd4 Code: aa0003f8 f8480f13 eb18027f 540006c0 (b9401264) [1]: CIFS_CRED="/root/cred.cifs" CIFS_USER="Administrator" CIFS_PASS="Password" CIFS_IP="X.X.X.X" CIFS_PATH="//${CIFS_IP}/Users/Administrator/Desktop/CIFS_TEST" CIFS_MNT="/mnt/smb" DEV="enp0s3" cat <<EOF > ${CIFS_CRED} username=${CIFS_USER} password=${CIFS_PASS} domain=EXAMPLE.COM EOF unshare -n bash -c " mkdir -p ${CIFS_MNT} ip netns attach root 1 ip link add eth0 type veth peer veth0 netns root ip link set eth0 up ip -n root link set veth0 up ip addr add 192.168.0.2/24 dev eth0 ip -n root addr add 192.168.0.1/24 dev veth0 ip route add default via 192.168.0.1 dev eth0 ip netns exec root sysctl net.ipv4.ip_forward=1 ip netns exec root iptables -t nat -A POSTROUTING -s 192.168.0.2 -o ${DEV} -j MASQUERADE mount -t cifs ${CIFS_PATH} ${CIFS_MNT} -o vers=3.0,sec=ntlmssp,credentials=${CIFS_CRED},rsize=65536,wsize=65536,cache=none,echo_interval=1 touch ${CIFS_MNT}/a.txt ip netns exec root iptables -t nat -D POSTROUTING -s 192.168.0.2 -o ${DEV} -j MASQUERADE " umount ${CIFS_MNT} [2]: ref_tracker: net notrefcnt@000000004bbc008d has 1/1 users at sk_alloc (./include/net/net_namespace.h:339 net/core/sock.c:2227) inet_create (net/ipv4/af_inet.c:326 net/ipv4/af_inet.c:252) __sock_create (net/socket.c:1576) generic_ip_connect (fs/smb/client/connect.c:3075) cifs_get_tcp_session.part.0 (fs/smb/client/connect.c:3160 fs/smb/client/connect.c:1798) cifs_mount_get_session (fs/smb/client/trace.h:959 fs/smb/client/connect.c:3366) dfs_mount_share (fs/smb/client/dfs.c:63 fs/smb/client/dfs.c:285) cifs_mount (fs/smb/client/connect.c:3622) cifs_smb3_do_mount (fs/smb/client/cifsfs.c:949) smb3_get_tree (fs/smb/client/fs_context.c:784 fs/smb/client/fs_context.c:802 fs/smb/client/fs_context.c:794) vfs_get_tree (fs/super.c:1800) path_mount (fs/namespace.c:3508 fs/namespace.c:3834) __x64_sys_mount (fs/namespace.c:3848 fs/namespace.c:4057 fs/namespace.c:4034 fs/namespace.c:4034) do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Fixes: 26abe14 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Tom Talpey <tom@talpey.com> Signed-off-by: Steve French <stfrench@microsoft.com>

Unloading the ice driver while switchdev port representors are added to a bridge can lead to kernel panic. Reproducer: modprobe ice devlink dev eswitch set $PF1_PCI mode switchdev ip link add $BR type bridge ip link set $BR up echo 2 > /sys/class/net/$PF1/device/sriov_numvfs sleep 2 ip link set $PF1 master $BR ip link set $VF1_PR master $BR ip link set $VF2_PR master $BR ip link set $PF1 up ip link set $VF1_PR up ip link set $VF2_PR up ip link set $VF1 up rmmod irdma ice When unloading the driver, ice_eswitch_detach() is eventually called as part of VF freeing. First, it removes a port representor from xarray, then unregister_netdev() is called (via repr->ops.rem()), finally representor is deallocated. The problem comes from the bridge doing its own deinit at the same time. unregister_netdev() triggers a notifier chain, resulting in ice_eswitch_br_port_deinit() being called. It should set repr->br_port = NULL, but this does not happen since repr has already been removed from xarray and is not found. Regardless, it finishes up deallocating br_port. At this point, repr is still not freed and an fdb event can happen, in which ice_eswitch_br_fdb_event_work() takes repr->br_port and tries to use it, which causes a panic (use after free). Note that this only happens with 2 or more port representors added to the bridge, since with only one representor port, the bridge deinit is slightly different (ice_eswitch_br_port_deinit() is called via ice_eswitch_br_ports_flush(), not ice_eswitch_br_port_unlink()). Trace: Oops: general protection fault, probably for non-canonical address 0xf129010fd1a93284: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: maybe wild-memory-access in range [0x8948287e8d499420-0x8948287e8d499427] (...) Workqueue: ice_bridge_wq ice_eswitch_br_fdb_event_work [ice] RIP: 0010:__rht_bucket_nested+0xb4/0x180 (...) Call Trace: (...) ice_eswitch_br_fdb_find+0x3fa/0x550 [ice] ? __pfx_ice_eswitch_br_fdb_find+0x10/0x10 [ice] ice_eswitch_br_fdb_event_work+0x2de/0x1e60 [ice] ? __schedule+0xf60/0x5210 ? mutex_lock+0x91/0xe0 ? __pfx_ice_eswitch_br_fdb_event_work+0x10/0x10 [ice] ? ice_eswitch_br_update_work+0x1f4/0x310 [ice] (...) A workaround is available: brctl setageing $BR 0, which stops the bridge from adding fdb entries altogether. Change the order of operations in ice_eswitch_detach(): move the call to unregister_netdev() before removing repr from xarray. This way repr->br_port will be correctly set to NULL in ice_eswitch_br_port_deinit(), preventing a panic. Fixes: fff292b ("ice: add VF representors one by one") Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Marcin Szycik <marcin.szycik@linux.intel.com> Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

The RTC update work involves runtime resuming the UFS controller. Hence, only start the RTC update work after runtime power management in the UFS driver has been fully initialized. This patch fixes the following kernel crash: Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Workqueue: events ufshcd_rtc_work Call trace: _raw_spin_lock_irqsave+0x34/0x8c (P) pm_runtime_get_if_active+0x24/0x9c (L) pm_runtime_get_if_active+0x24/0x9c ufshcd_rtc_work+0x138/0x1b4 process_one_work+0x148/0x288 worker_thread+0x2cc/0x3d4 kthread+0x110/0x114 ret_from_fork+0x10/0x20 Reported-by: Neil Armstrong <neil.armstrong@linaro.org> Closes: https://lore.kernel.org/linux-scsi/0c0bc528-fdc2-4106-bc99-f23ae377f6f5@linaro.org/ Fixes: 6bf999e ("scsi: ufs: core: Add UFS RTC support") Cc: Bean Huo <beanhuo@micron.com> Cc: stable@vger.kernel.org Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20241031212632.2799127-1-bvanassche@acm.org Reviewed-by: Peter Wang <peter.wang@mediatek.com> Reviewed-by: Bean Huo <beanhuo@micron.com> Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-HDK Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

In unlikely event that we fail during sending the new VF GGTT configuration to the GuC, we will free only the GGTT node data struct but will miss to release the actual GGTT allocation. This will later lead to list corruption, GGTT space leak and finally risking crash when unloading the driver: [ ] ... [drm] GT0: PF: Failed to provision VF1 with 1073741824 (1.00 GiB) GGTT (-EIO) [ ] ... [drm] GT0: PF: VF1 provisioning remains at 0 (0 B) GGTT [ ] list_add corruption. next->prev should be prev (ffff88813cfcd628), but was 0000000000000000. (next=ffff88813cfe2028). [ ] RIP: 0010:__list_add_valid_or_report+0x6b/0xb0 [ ] Call Trace: [ ] drm_mm_insert_node_in_range+0x2c0/0x4e0 [ ] xe_ggtt_node_insert+0x46/0x70 [xe] [ ] pf_provision_vf_ggtt+0x7f5/0xa70 [xe] [ ] xe_gt_sriov_pf_config_set_ggtt+0x5e/0x770 [xe] [ ] ggtt_set+0x4b/0x70 [xe] [ ] simple_attr_write_xsigned.constprop.0.isra.0+0xb0/0x110 [ ] ... [drm] GT0: PF: Failed to provision VF1 with 1073741824 (1.00 GiB) GGTT (-ENOSPC) [ ] ... [drm] GT0: PF: VF1 provisioning remains at 0 (0 B) GGTT [ ] Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b7b: 0000 [#1] PREEMPT SMP NOPTI [ ] RIP: 0010:drm_mm_remove_node+0x1b7/0x390 [ ] Call Trace: [ ] <TASK> [ ] ? die_addr+0x2e/0x80 [ ] ? exc_general_protection+0x1a1/0x3e0 [ ] ? asm_exc_general_protection+0x22/0x30 [ ] ? drm_mm_remove_node+0x1b7/0x390 [ ] ggtt_node_remove+0xa5/0xf0 [xe] [ ] xe_ggtt_node_remove+0x35/0x70 [xe] [ ] xe_ttm_bo_destroy+0x123/0x220 [xe] [ ] intel_user_framebuffer_destroy+0x44/0x70 [xe] [ ] intel_plane_destroy_state+0x3b/0xc0 [xe] [ ] drm_atomic_state_default_clear+0x1cd/0x2f0 [ ] intel_atomic_state_clear+0x9/0x20 [xe] [ ] __drm_atomic_state_free+0x1d/0xb0 Fix that by using pf_release_ggtt() on the error path, which now works regardless if the node has GGTT allocation or not. Fixes: 34e8042 ("drm/xe: Make xe_ggtt_node struct independent") Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Matthew Auld <matthew.auld@intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20241104144901.1903-1-michal.wajdeczko@intel.com (cherry picked from commit 43b1dd2) Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

vp_modern_avq_cleanup() and vp_del_vqs() clean up admin vq resources by virtio_pci_vq_info pointer. The info pointer of admin vq is stored in vp_dev->admin_vq.info instead of vp_dev->vqs[]. Using the info pointer from vp_dev->vqs[] for admin vq causes a kernel NULL pointer dereference bug. In vp_modern_avq_cleanup() and vp_del_vqs(), get the info pointer from vp_dev->admin_vq.info for admin vq to clean up the resources. Also make info ptr as argument of vp_del_vq() to be symmetric with vp_setup_vq(). vp_reset calls vp_modern_avq_cleanup, and causes the Call Trace: ================================================================== BUG: kernel NULL pointer dereference, address:0000000000000000 ... CPU: 49 UID: 0 PID: 4439 Comm: modprobe Not tainted 6.11.0-rc5 #1 RIP: 0010:vp_reset+0x57/0x90 [virtio_pci] Call Trace: <TASK> ... ? vp_reset+0x57/0x90 [virtio_pci] ? vp_reset+0x38/0x90 [virtio_pci] virtio_reset_device+0x1d/0x30 remove_vq_common+0x1c/0x1a0 [virtio_net] virtnet_remove+0xa1/0xc0 [virtio_net] virtio_dev_remove+0x46/0xa0 ... virtio_pci_driver_exit+0x14/0x810 [virtio_pci] ================================================================== Fixes: 4c3b54a ("virtio_pci_modern: use completion instead of busy loop to wait on admin cmd result") Signed-off-by: Feng Liu <feliu@nvidia.com> Signed-off-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Parav Pandit <parav@nvidia.com> Message-Id: <20241024135406.81388-1-feliu@nvidia.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

In the error recovery path of mlx5_vdpa_dev_add(), the cleanup is executed and at the end put_device() is called which ends up calling mlx5_vdpa_free(). This function will execute the same cleanup all over again. Most resources support being cleaned up twice, but the recent mlx5_vdpa_destroy_mr_resources() doesn't. This change drops the explicit cleanup from within the mlx5_vdpa_dev_add() and lets mlx5_vdpa_free() do its work. This issue was discovered while trying to add 2 vdpa devices with the same name: $> vdpa dev add name vdpa-0 mgmtdev auxiliary/mlx5_core.sf.2 $> vdpa dev add name vdpa-0 mgmtdev auxiliary/mlx5_core.sf.3 ... yields the following dump: BUG: kernel NULL pointer dereference, address: 00000000000000b8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP CPU: 4 UID: 0 PID: 2811 Comm: vdpa Not tainted 6.12.0-rc6 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:destroy_workqueue+0xe/0x2a0 Code: ... RSP: 0018:ffff88814920b9a8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff888105c10000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffff888100400168 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff888100120c00 R09: ffffffff828578c0 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888131fd99a0 R14: 0000000000000000 R15: ffff888105c10580 FS: 00007fdfa6b4f740(0000) GS:ffff88852ca00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000b8 CR3: 000000018db09006 CR4: 0000000000372eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __die+0x20/0x60 ? page_fault_oops+0x150/0x3e0 ? exc_page_fault+0x74/0x130 ? asm_exc_page_fault+0x22/0x30 ? destroy_workqueue+0xe/0x2a0 mlx5_vdpa_destroy_mr_resources+0x2b/0x40 [mlx5_vdpa] mlx5_vdpa_free+0x45/0x150 [mlx5_vdpa] vdpa_release_dev+0x1e/0x50 [vdpa] device_release+0x31/0x90 kobject_put+0x8d/0x230 mlx5_vdpa_dev_add+0x328/0x8b0 [mlx5_vdpa] vdpa_nl_cmd_dev_add_set_doit+0x2b8/0x4c0 [vdpa] genl_family_rcv_msg_doit+0xd0/0x120 genl_rcv_msg+0x180/0x2b0 ? __vdpa_alloc_device+0x1b0/0x1b0 [vdpa] ? genl_family_rcv_msg_dumpit+0xf0/0xf0 netlink_rcv_skb+0x54/0x100 genl_rcv+0x24/0x40 netlink_unicast+0x1fc/0x2d0 netlink_sendmsg+0x1e4/0x410 __sock_sendmsg+0x38/0x60 ? sockfd_lookup_light+0x12/0x60 __sys_sendto+0x105/0x160 ? __count_memcg_events+0x53/0xe0 ? handle_mm_fault+0x100/0x220 ? do_user_addr_fault+0x40d/0x620 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x4c/0x100 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7fdfa6c66b57 Code: ... RSP: 002b:00007ffeace22998 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055a498608350 RCX: 00007fdfa6c66b57 RDX: 000000000000006c RSI: 000055a498608350 RDI: 0000000000000003 RBP: 00007ffeace229c0 R08: 00007fdfa6d35200 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 000055a4986082a0 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffeace233f3 </TASK> Modules linked in: ... CR2: 00000000000000b8 Fixes: 6211165 ("vdpa/mlx5: Postpone MR deletion") Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com> Message-Id: <20241105185101.1323272-2-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Eugenio Pérez <eperezma@redhat.com>

Currently, an interrupt can be triggered during a GPU reset, which can lead to GPU hangs and NULL pointer dereference in an interrupt context as shown in the following trace: [ 314.035040] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0 [ 314.043822] Mem abort info: [ 314.046606] ESR = 0x0000000096000005 [ 314.050347] EC = 0x25: DABT (current EL), IL = 32 bits [ 314.055651] SET = 0, FnV = 0 [ 314.058695] EA = 0, S1PTW = 0 [ 314.061826] FSC = 0x05: level 1 translation fault [ 314.066694] Data abort info: [ 314.069564] ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 [ 314.075039] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 314.080080] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 314.085382] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000102728000 [ 314.091814] [00000000000000c0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000 [ 314.100511] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP [ 314.106770] Modules linked in: v3d i2c_brcmstb vc4 snd_soc_hdmi_codec gpu_sched drm_shmem_helper drm_display_helper cec drm_dma_helper drm_kms_helper drm drm_panel_orientation_quirks snd_soc_core snd_compress snd_pcm_dmaengine snd_pcm snd_timer snd backlight [ 314.129654] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.25+rpt-rpi-v8 #1 Debian 1:6.12.25-1+rpt1 [ 314.139388] Hardware name: Raspberry Pi 4 Model B Rev 1.4 (DT) [ 314.145211] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 314.152165] pc : v3d_irq+0xec/0x2e0 [v3d] [ 314.156187] lr : v3d_irq+0xe0/0x2e0 [v3d] [ 314.160198] sp : ffffffc080003ea0 [ 314.163502] x29: ffffffc080003ea0 x28: ffffffec1f184980 x27: 021202b000000000 [ 314.170633] x26: ffffffec1f17f630 x25: ffffff8101372000 x24: ffffffec1f17d9f0 [ 314.177764] x23: 000000000000002a x22: 000000000000002a x21: ffffff8103252000 [ 314.184895] x20: 0000000000000001 x19: 00000000deadbeef x18: 0000000000000000 [ 314.192026] x17: ffffff94e51d2000 x16: ffffffec1dac3cb0 x15: c306000000000000 [ 314.199156] x14: 0000000000000000 x13: b2fc982e03cc5168 x12: 0000000000000001 [ 314.206286] x11: ffffff8103f8bcc0 x10: ffffffec1f196868 x9 : ffffffec1dac3874 [ 314.213416] x8 : 0000000000000000 x7 : 0000000000042a3a x6 : ffffff810017a180 [ 314.220547] x5 : ffffffec1ebad400 x4 : ffffffec1ebad320 x3 : 00000000000bebeb [ 314.227677] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 [ 314.234807] Call trace: [ 314.237243] v3d_irq+0xec/0x2e0 [v3d] [ 314.240906] __handle_irq_event_percpu+0x58/0x218 [ 314.245609] handle_irq_event+0x54/0xb8 [ 314.249439] handle_fasteoi_irq+0xac/0x240 [ 314.253527] handle_irq_desc+0x48/0x68 [ 314.257269] generic_handle_domain_irq+0x24/0x38 [ 314.261879] gic_handle_irq+0x48/0xd8 [ 314.265533] call_on_irq_stack+0x24/0x58 [ 314.269448] do_interrupt_handler+0x88/0x98 [ 314.273624] el1_interrupt+0x34/0x68 [ 314.277193] el1h_64_irq_handler+0x18/0x28 [ 314.281281] el1h_64_irq+0x64/0x68 [ 314.284673] default_idle_call+0x3c/0x168 [ 314.288675] do_idle+0x1fc/0x230 [ 314.291895] cpu_startup_entry+0x3c/0x50 [ 314.295810] rest_init+0xe4/0xf0 [ 314.299030] start_kernel+0x5e8/0x790 [ 314.302684] __primary_switched+0x80/0x90 [ 314.306691] Code: 940029eb 360ffc13 f9442ea0 52800001 (f9406017) [ 314.312775] ---[ end trace 0000000000000000 ]--- [ 314.317384] Kernel panic - not syncing: Oops: Fatal exception in interrupt [ 314.324249] SMP: stopping secondary CPUs [ 314.328167] Kernel Offset: 0x2b9da00000 from 0xffffffc080000000 [ 314.334076] PHYS_OFFSET: 0x0 [ 314.336946] CPU features: 0x08,00002013,c0200000,0200421b [ 314.342337] Memory Limit: none [ 314.345382] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]--- Before resetting the GPU, it's necessary to disable all interrupts and deal with any interrupt handler still in-flight. Otherwise, the GPU might reset with jobs still running, or yet, an interrupt could be handled during the reset. Cc: stable@vger.kernel.org Fixes: 57692c9 ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+") Reviewed-by: Juan A. Suarez <jasuarez@igalia.com> Reviewed-by: Iago Toral Quiroga <itoral@igalia.com> Link: https://lore.kernel.org/r/20250628224243.47599-1-mcanal@igalia.com Signed-off-by: Maíra Canal <mcanal@igalia.com>

virtio-serial does not work with kgdboc. I know it's an unusual use case as one can always just use the qemu gdbserver, but still... root@aa98fce09d67:/# echo a > /dev/hvc0 root@aa98fce09d67:/# echo a > /dev/hvc1 a root@aa98fce09d67:/# echo g > /proc/sysrq-trigger [ 11.997004][ T146] sysrq: DEBUG [ 11.998003][ C9] BUG: kernel NULL pointer dereference, address: 0000000000000248 [ 11.998003][ C9] #PF: supervisor read access in kernel mode [ 11.998003][ C9] #PF: error_code(0x0000) - not-present page [ 11.998003][ C9] PGD 0 P4D 0 [ 11.998003][ C9] Oops: Oops: 0000 [#1] PREEMPT SMP [ 11.998003][ C9] CPU: 9 UID: 0 PID: 146 Comm: bash Not tainted 6.14.0-dev-00032-g11aa3e204678-dirty torvalds#122 [ 11.998003][ C9] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 [ 11.998003][ C9] RIP: 0010:hvc_poll_put_char (drivers/tty/hvc/hvc_console.c:879) [ 11.998003][ C9] Code: 00 00 ff 00 eb e8 e8 e0 7d 2a 00 f3 0f 1e fa 0f 1f 44 00 00 55 48 89 e5 53 48 83 ec 08 48 8b 87 80 00 00 00 88 55 f4 48 8b 00 <48> 8b 98 48 02 00 00 48 8b 83 90 01 00 00 8b bb 8c 01 00 00 ba 01 All code ======== 0: 00 00 add %al,(%rax) 2: ff 00 incl (%rax) 4: eb e8 jmp 0xffffffffffffffee 6: e8 e0 7d 2a 00 call 0x2a7deb b: f3 0f 1e fa endbr64 f: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 14: 55 push %rbp 15: 48 89 e5 mov %rsp,%rbp 18: 53 push %rbx 19: 48 83 ec 08 sub $0x8,%rsp 1d: 48 8b 87 80 00 00 00 mov 0x80(%rdi),%rax 24: 88 55 f4 mov %dl,-0xc(%rbp) 27: 48 8b 00 mov (%rax),%rax 2a:* 48 8b 98 48 02 00 00 mov 0x248(%rax),%rbx <-- trapping instruction 31: 48 8b 83 90 01 00 00 mov 0x190(%rbx),%rax 38: 8b bb 8c 01 00 00 mov 0x18c(%rbx),%edi 3e: ba .byte 0xba 3f: 01 .byte 0x1 Code starting with the faulting instruction =========================================== 0: 48 8b 98 48 02 00 00 mov 0x248(%rax),%rbx 7: 48 8b 83 90 01 00 00 mov 0x190(%rbx),%rax e: 8b bb 8c 01 00 00 mov 0x18c(%rbx),%edi 14: ba .byte 0xba 15: 01 .byte 0x1 [ 11.998003][ C9] RSP: 0018:ffffc90000507950 EFLAGS: 00010086 [ 11.998003][ C9] RAX: 0000000000000000 RBX: ffffffff8279c241 RCX: ffffffff81c712c0 [ 11.998003][ C9] RDX: 000000000000000a RSI: 0000000000000000 RDI: ffff888100a81180 [ 11.998003][ C9] RBP: ffffc90000507960 R08: 0000000000000034 R09: 0000000000000000 [ 11.998003][ C9] R10: 0000000000000001 R11: 0000000000000004 R12: 0000000000000034 [ 11.998003][ C9] R13: ffffffff8279c240 R14: ffffffff8279c274 R15: 00000000ffffffff [ 11.998003][ C9] FS: 00007fcb62844740(0000) GS:ffff88817bc40000(0000) knlGS:0000000000000000 [ 11.998003][ C9] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 11.998003][ C9] CR2: 0000000000000248 CR3: 0000000101d68003 CR4: 0000000000370ef0 [ 11.998003][ C9] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 11.998003][ C9] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 11.998003][ C9] Call Trace: [ 11.998003][ C9] <TASK> [ 11.998003][ C9] ? show_regs (arch/x86/kernel/dumpstack.c:479) [ 11.998003][ C9] ? __die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434) [ 11.998003][ C9] ? page_fault_oops (arch/x86/mm/fault.c:714) [ 11.998003][ C9] ? do_user_addr_fault (arch/x86/mm/fault.c:1235) [ 11.998003][ C9] ? exc_page_fault (./arch/x86/include/asm/irqflags.h:37 ./arch/x86/include/asm/irqflags.h:92 arch/x86/mm/fault.c:1488 arch/x86/mm/fault.c:1538) [ 11.998003][ C9] ? asm_exc_page_fault (./arch/x86/include/asm/idtentry.h:623) [ 11.998003][ C9] ? hvc_poll_put_char (drivers/tty/hvc/hvc_console.c:879) [ 11.998003][ C9] kgdboc_put_char (drivers/tty/serial/kgdboc.c:354) [ 11.998003][ C9] kdb_msg_write.part.0 (kernel/debug/kdb/kdb_io.c:574) [ 11.998003][ C9] vkdb_printf (kernel/debug/kdb/kdb_io.c:568 kernel/debug/kdb/kdb_io.c:766) [ 11.998003][ C9] kdb_printf (kernel/debug/kdb/kdb_io.c:901) [ 11.998003][ C9] kdb_main_loop (kernel/debug/kdb/kdb_main.c:1207 kernel/debug/kdb/kdb_main.c:1426) [ 11.998003][ C9] ? module_event (kernel/debug/debug_core.c:880) [ 11.998003][ C9] kdb_stub (kernel/debug/kdb/kdb_debugger.c:47 kernel/debug/kdb/kdb_debugger.c:141) [ 11.998003][ C9] kgdb_cpu_enter (kernel/debug/debug_core.c:740) [ 11.998003][ C9] kgdb_handle_exception (kernel/debug/debug_core.c:865) [ 11.998003][ C9] __kgdb_notify (arch/x86/kernel/kgdb.c:548) [ 11.998003][ C9] kgdb_notify (./arch/x86/include/asm/irqflags.h:154 arch/x86/kernel/kgdb.c:582) [ 11.998003][ C9] notifier_call_chain (kernel/notifier.c:87) [ 11.998003][ C9] notify_die (kernel/notifier.c:223 kernel/notifier.c:588) [ 11.998003][ C9] exc_int3 (arch/x86/kernel/traps.c:811) [ 11.998003][ C9] asm_exc_int3 (./arch/x86/include/asm/idtentry.h:622) [ 11.998003][ C9] RIP: 0010:kgdb_breakpoint (kernel/debug/debug_core.c:1222) [ 11.998003][ C9] Code: e5 5d c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 f3 0f 1e fa 0f 1f 44 00 00 55 48 89 e5 f0 ff 05 b4 88 42 01 0f ae f8 cc <0f> ae f8 f0 ff 0d a6 88 42 01 5d c3 66 66 2e 0f 1f 84 00 00 00 00 All code ======== 0: e5 5d in $0x5d,%eax 2: c3 ret 3: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) a: 00 00 00 00 e: 0f 1f 40 00 nopl 0x0(%rax) 12: f3 0f 1e fa endbr64 16: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1b: 55 push %rbp 1c: 48 89 e5 mov %rsp,%rbp 1f: f0 ff 05 b4 88 42 01 lock incl 0x14288b4(%rip) # 0x14288da 26: 0f ae f8 sfence 29: cc int3 2a:* 0f ae f8 sfence <-- trapping instruction 2d: f0 ff 0d a6 88 42 01 lock decl 0x14288a6(%rip) # 0x14288da 34: 5d pop %rbp 35: c3 ret 36: 66 data16 37: 66 data16 38: 2e cs 39: 0f .byte 0xf 3a: 1f (bad) 3b: 84 00 test %al,(%rax) 3d: 00 00 add %al,(%rax) ... Code starting with the faulting instruction =========================================== 0: 0f ae f8 sfence 3: f0 ff 0d a6 88 42 01 lock decl 0x14288a6(%rip) # 0x14288b0 a: 5d pop %rbp b: c3 ret c: 66 data16 d: 66 data16 e: 2e cs f: 0f .byte 0xf 10: 1f (bad) 11: 84 00 test %al,(%rax) 13: 00 00 add %al,(%rax) ... [ 11.998003][ C9] RSP: 0018:ffffc90000507da8 EFLAGS: 00000202 [ 11.998003][ C9] RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00000000ffffefff [ 11.998003][ C9] RDX: 0000000000000000 RSI: ffffc90000507c48 RDI: 0000000000000067 [ 11.998003][ C9] RBP: ffffc90000507da8 R08: 0000000000004ffb R09: 00000000ffffefff [ 11.998003][ C9] R10: 0000000000000001 R11: ffffffff8244fd20 R12: ffffffff81c1f240 [ 11.998003][ C9] R13: 0000000000000000 R14: 0000000000000067 R15: 000055ce20745a40 [ 11.998003][ C9] ? kgdb_breakpoint (kernel/debug/debug_core.c:1222) [ 11.998003][ C9] sysrq_handle_dbg (kernel/debug/debug_core.c:987) [ 11.998003][ C9] __handle_sysrq (./include/linux/rcupdate.h:882 drivers/tty/sysrq.c:634) [ 11.998003][ C9] write_sysrq_trigger (drivers/tty/sysrq.c:1182) [ 11.998003][ C9] proc_reg_write (./arch/x86/include/asm/atomic.h:85 ./include/linux/atomic/atomic-arch-fallback.h:787 ./include/linux/atomic/atomic-arch-fallback.h:1238 ./include/linux/atomic/atomic-instrumented.h:611 fs/proc/inode.c:205 fs/proc/inode.c:343) [ 11.998003][ C9] vfs_write (fs/read_write.c:677) [ 11.998003][ C9] ksys_write (fs/read_write.c:731) [ 11.998003][ C9] __x64_sys_write (fs/read_write.c:739) [ 11.998003][ C9] x64_sys_call (arch/x86/entry/syscall_64.c:36) [ 11.998003][ C9] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) [ 11.998003][ C9] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 11.998003][ C9] RIP: 0033:0x7fcb6293f300 [ 11.998003][ C9] Code: 40 00 48 8b 15 01 9b 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d e1 22 0e 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89 All code ======== 0: 40 00 48 8b rex add %cl,-0x75(%rax) 4: 15 01 9b 0d 00 adc $0xd9b01,%eax 9: f7 d8 neg %eax b: 64 89 02 mov %eax,%fs:(%rdx) e: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax 15: eb b7 jmp 0xffffffffffffffce 17: 0f 1f 00 nopl (%rax) 1a: 80 3d e1 22 0e 00 00 cmpb $0x0,0xe22e1(%rip) # 0xe2302 21: 74 17 je 0x3a 23: b8 01 00 00 00 mov $0x1,%eax 28: 0f 05 syscall 2a:* 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction 30: 77 58 ja 0x8a 32: c3 ret 33: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 3a: 48 83 ec 28 sub $0x28,%rsp 3e: 48 rex.W 3f: 89 .byte 0x89 Code starting with the faulting instruction =========================================== 0: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax 6: 77 58 ja 0x60 8: c3 ret 9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 10: 48 83 ec 28 sub $0x28,%rsp 14: 48 rex.W 15: 89 .byte 0x89 [ 11.998003][ C9] RSP: 002b:00007fffbfbfcf78 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 [ 11.998003][ C9] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fcb6293f300 [ 11.998003][ C9] RDX: 0000000000000002 RSI: 000055ce20745a40 RDI: 0000000000000001 [ 11.998003][ C9] RBP: 000055ce20745a40 R08: 0000000000000007 R09: 0000000000000073 [ 11.998003][ C9] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002 [ 11.998003][ C9] R13: 00007fcb62a1a760 R14: 0000000000000002 R15: 00007fcb62a159e0 [ 11.998003][ C9] </TASK> [ 11.998003][ C9] Modules linked in: [ 11.998003][ C9] KGDB: re-enter exception: ALL breakpoints killed [ 11.998003][ C9] CR2: 0000000000000248 [ 11.998003][ C9] ---[ end trace 0000000000000000 ]---

get_id_range() expects a positive value as first argument but get_random_u8() can return 0. Fix this by clamping it. Validated by running the test in a for loop for 1000 times. Note that MAX() is wrong as it is only supposed to be used for constants, but max() is good here. [..] ok 9 test_range2_rand1 [..] ok 10 test_range2_rand2 [..] ok 11 test_range2_rand15 [..] ------------[ cut here ]------------ [..] WARNING: CPU: 6 PID: 104 at security/landlock/id.c:99 test_range2_rand16 (security/landlock/id.c:99 (discriminator 1) security/landlock/id.c:234 (discriminator 1)) [..] Modules linked in: [..] CPU: 6 UID: 0 PID: 104 Comm: kunit_try_catch Tainted: G N 6.16.0-rc1-dev-00001-g314a2f98b65f #1 PREEMPT(undef) [..] Tainted: [N]=TEST [..] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [..] RIP: 0010:test_range2_rand16 (security/landlock/id.c:99 (discriminator 1) security/landlock/id.c:234 (discriminator 1)) [..] Code: 49 c7 c0 10 70 30 82 4c 89 ff 48 c7 c6 a0 63 1e 83 49 c7 45 a0 e0 63 1e 83 e8 3f 95 17 00 e9 1f ff ff ff 0f 0b e9 df fd ff ff <0f> 0b ba 01 00 00 00 e9 68 fe ff ff 49 89 45 a8 49 8d 4d a0 45 31 [..] RSP: 0000:ffff888104eb7c78 EFLAGS: 00010246 [..] RAX: 0000000000000000 RBX: 000000000870822c RCX: 0000000000000000 ^^^^^^^^^^^^^^^^ [..] [..] Call Trace: [..] [..] ---[ end trace 0000000000000000 ]--- [..] ok 12 test_range2_rand16 [..] # landlock_id: pass:12 fail:0 skip:0 total:12 [..] # Totals: pass:12 fail:0 skip:0 total:12 [..] ok 1 landlock_id Fixes: d9d2a68 ("landlock: Add unique ID generator") Signed-off-by: Tingmao Wang <m@maowtm.org> Link: https://lore.kernel.org/r/73e28efc5b8cc394608b99d5bc2596ca917d7c4a.1750003733.git.m@maowtm.org [mic: Minor cosmetic improvements] Signed-off-by: Mickaël Salaün <mic@digikod.net>

When gmin_get_config_var() calls efi.get_variable() and the EFI variable is larger than the expected buffer size, two behaviors combine to create a stack buffer overflow: 1. gmin_get_config_var() does not return the proper error code when efi.get_variable() fails. It returns the stale 'ret' value from earlier operations instead of indicating the EFI failure. 2. When efi.get_variable() returns EFI_BUFFER_TOO_SMALL, it updates *out_len to the required buffer size but writes no data to the output buffer. However, due to bug #1, gmin_get_var_int() believes the call succeeded. The caller gmin_get_var_int() then performs: - Allocates val[CFG_VAR_NAME_MAX + 1] (65 bytes) on stack - Calls gmin_get_config_var(dev, is_gmin, var, val, &len) with len=64 - If EFI variable is >64 bytes, efi.get_variable() sets len=required_size - Due to bug #1, thinks call succeeded with len=required_size - Executes val[len] = 0, writing past end of 65-byte stack buffer This creates a stack buffer overflow when EFI variables are larger than 64 bytes. Since EFI variables can be controlled by firmware or system configuration, this could potentially be exploited for code execution. Fix the bug by returning proper error codes from gmin_get_config_var() based on EFI status instead of stale 'ret' value. The gmin_get_var_int() function is called during device initialization for camera sensor configuration on Intel Bay Trail and Cherry Trail platforms using the atomisp camera stack. Reported-by: zepta <z3ptaa@gmail.com> Closes: https://lore.kernel.org/all/CAPBS6KoQyM7FMdPwOuXteXsOe44X4H3F8Fw+y_qWq6E+OdmxQA@mail.gmail.com Fixes: 38d4f74 ("media: atomisp_gmin_platform: stop abusing efivar API") Reviewed-by: Hans de Goede <hansg@kernel.org> Link: https://lore.kernel.org/r/20250724080756.work.741-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>

…l/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.17, round #1 - Host driver for GICv5, the next generation interrupt controller for arm64, including support for interrupt routing, MSIs, interrupt translation and wired interrupts. - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on GICv5 hardware, leveraging the legacy VGIC interface. - Userspace control of the 'nASSGIcap' GICv3 feature, allowing userspace to disable support for SGIs w/o an active state on hardware that previously advertised it unconditionally. - Map supporting endpoints with cacheable memory attributes on systems with FEAT_S2FWB and DIC where KVM no longer needs to perform cache maintenance on the address range. - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest hypervisor to inject external aborts into an L2 VM and take traps of masked external aborts to the hypervisor. - Convert more system register sanitization to the config-driven implementation. - Fixes to the visibility of EL2 registers, namely making VGICv3 system registers accessible through the VGIC device instead of the ONE_REG vCPU ioctls. - Various cleanups and minor fixes.

When sending a packet with virtio_net_hdr to tun device, if the gso_type in virtio_net_hdr is SKB_GSO_UDP and the gso_size is less than udphdr size, below crash may happen. ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:4572! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 62 Comm: mytest Not tainted 6.16.0-rc7 torvalds#203 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:skb_pull_rcsum+0x8e/0xa0 Code: 00 00 5b c3 cc cc cc cc 8b 93 88 00 00 00 f7 da e8 37 44 38 00 f7 d8 89 83 88 00 00 00 48 8b 83 c8 00 00 00 5b c3 cc cc cc cc <0f> 0b 0f 0b 66 66 2e 0f 1f 84 00 000 RSP: 0018:ffffc900001fba38 EFLAGS: 00000297 RAX: 0000000000000004 RBX: ffff8880040c1000 RCX: ffffc900001fb948 RDX: ffff888003e6d700 RSI: 0000000000000008 RDI: ffff88800411a062 RBP: ffff8880040c1000 R08: 0000000000000000 R09: 0000000000000001 R10: ffff888003606c00 R11: 0000000000000001 R12: 0000000000000000 R13: ffff888004060900 R14: ffff888004050000 R15: ffff888004060900 FS: 000000002406d3c0(0000) GS:ffff888084a19000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000040 CR3: 0000000004007000 CR4: 00000000000006f0 Call Trace: <TASK> udp_queue_rcv_one_skb+0x176/0x4b0 net/ipv4/udp.c:2445 udp_queue_rcv_skb+0x155/0x1f0 net/ipv4/udp.c:2475 udp_unicast_rcv_skb+0x71/0x90 net/ipv4/udp.c:2626 __udp4_lib_rcv+0x433/0xb00 net/ipv4/udp.c:2690 ip_protocol_deliver_rcu+0xa6/0x160 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x72/0x90 net/ipv4/ip_input.c:233 ip_sublist_rcv_finish+0x5f/0x70 net/ipv4/ip_input.c:579 ip_sublist_rcv+0x122/0x1b0 net/ipv4/ip_input.c:636 ip_list_rcv+0xf7/0x130 net/ipv4/ip_input.c:670 __netif_receive_skb_list_core+0x21d/0x240 net/core/dev.c:6067 netif_receive_skb_list_internal+0x186/0x2b0 net/core/dev.c:6210 napi_complete_done+0x78/0x180 net/core/dev.c:6580 tun_get_user+0xa63/0x1120 drivers/net/tun.c:1909 tun_chr_write_iter+0x65/0xb0 drivers/net/tun.c:1984 vfs_write+0x300/0x420 fs/read_write.c:593 ksys_write+0x60/0xd0 fs/read_write.c:686 do_syscall_64+0x50/0x1c0 arch/x86/entry/syscall_64.c:63 </TASK> To trigger gso segment in udp_queue_rcv_skb(), we should also set option UDP_ENCAP_ESPINUDP to enable udp_sk(sk)->encap_rcv. When the encap_rcv hook return 1 in udp_queue_rcv_one_skb(), udp_csum_pull_header() will try to pull udphdr, but the skb size has been segmented to gso size, which leads to this crash. Previous commit cf329aa ("udp: cope with UDP GRO packet misdirection") introduces segmentation in UDP receive path only for GRO, which was never intended to be used for UFO, so drop UFO packets in udp_rcv_segment(). Link: https://lore.kernel.org/netdev/20250724083005.3918375-1-wangliang74@huawei.com/ Link: https://lore.kernel.org/netdev/20250729123907.3318425-1-wangliang74@huawei.com/ Fixes: cf329aa ("udp: cope with UDP GRO packet misdirection") Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Signed-off-by: Wang Liang <wangliang74@huawei.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250730101458.3470788-1-wangliang74@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Our testcase trigger panic: BUG: kernel NULL pointer dereference, address: 00000000000000e0 ... Oops: Oops: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 85 Comm: kworker/2:1 Not tainted 6.16.0+ torvalds#94 PREEMPT(none) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 Workqueue: md_misc md_start_sync RIP: 0010:rdev_addable+0x4d/0xf0 ... Call Trace: <TASK> md_start_sync+0x329/0x480 process_one_work+0x226/0x6d0 worker_thread+0x19e/0x340 kthread+0x10f/0x250 ret_from_fork+0x14d/0x180 ret_from_fork_asm+0x1a/0x30 </TASK> Modules linked in: raid10 CR2: 00000000000000e0 ---[ end trace 0000000000000000 ]--- RIP: 0010:rdev_addable+0x4d/0xf0 md_spares_need_change in md_start_sync will call rdev_addable which protected by rcu_read_lock/rcu_read_unlock. This rcu context will help protect rdev won't be released, but rdev->mddev will be set to NULL before we call synchronize_rcu in md_kick_rdev_from_array. Fix this by using READ_ONCE and check does rdev->mddev still alive. Fixes: bc08041 ("md: suspend array in md_start_sync() if array need reconfiguration") Fixes: 570b914 ("md: use RCU lock to protect traversal in md_spares_need_change()") Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://lore.kernel.org/linux-raid/20250731114530.776670-1-yangerkun@huawei.com Signed-off-by: Yu Kuai <yukuai3@huawei.com>

profile allocation is wrongly setting the number of entries on the rules vector before any ruleset is assigned. If profile allocation fails between ruleset allocation and assigning the first ruleset, free_ruleset() will be called with a null pointer resulting in an oops. [ 107.350226] kernel BUG at mm/slub.c:545! [ 107.350912] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 107.351447] CPU: 1 UID: 0 PID: 27 Comm: ksoftirqd/1 Not tainted 6.14.6-hwe-rlee287-dev+ #5 [ 107.353279] Hardware name:[ 107.350218] -QE-----------[ cutMU here ]--------- Ub--- [ 107.3502untu26] kernel BUG a 24t mm/slub.c:545.!04 P [ 107.350912]C ( Oops: invalid oi4pcode: 0000 [#1]40 PREEMPT SMP NOPFXTI + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 107.356054] RIP: 0010:__slab_free+0x152/0x340 [ 107.356444] Code: 00 4c 89 ff e8 0f ac df 00 48 8b 14 24 48 8b 4c 24 20 48 89 44 24 08 48 8b 03 48 c1 e8 09 83 e0 01 88 44 24 13 e9 71 ff ff ff <0f> 0b 41 f7 44 24 08 87 04 00 00 75 b2 eb a8 41 f7 44 24 08 87 04 [ 107.357856] RSP: 0018:ffffad4a800fbbb0 EFLAGS: 00010246 [ 107.358937] RAX: ffff97ebc2a88e70 RBX: ffffd759400aa200 RCX: 0000000000800074 [ 107.359976] RDX: ffff97ebc2a88e60 RSI: ffffd759400aa200 RDI: ffffad4a800fbc20 [ 107.360600] RBP: ffffad4a800fbc50 R08: 0000000000000001 R09: ffffffff86f02cf2 [ 107.361254] R10: 0000000000000000 R11: 0000000000000000 R12: ffff97ecc0049400 [ 107.361934] R13: ffff97ebc2a88e60 R14: ffff97ecc0049400 R15: 0000000000000000 [ 107.362597] FS: 0000000000000000(0000) GS:ffff97ecfb200000(0000) knlGS:0000000000000000 [ 107.363332] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 107.363784] CR2: 000061c9545ac000 CR3: 0000000047aa6000 CR4: 0000000000750ef0 [ 107.364331] PKRU: 55555554 [ 107.364545] Call Trace: [ 107.364761] <TASK> [ 107.364931] ? local_clock+0x15/0x30 [ 107.365219] ? srso_alias_return_thunk+0x5/0xfbef5 [ 107.365593] ? kfree_sensitive+0x32/0x70 [ 107.365900] kfree+0x29d/0x3a0 [ 107.366144] ? srso_alias_return_thunk+0x5/0xfbef5 [ 107.366510] ? local_clock_noinstr+0xe/0xd0 [ 107.366841] ? srso_alias_return_thunk+0x5/0xfbef5 [ 107.367209] kfree_sensitive+0x32/0x70 [ 107.367502] aa_free_profile.part.0+0xa2/0x400 [ 107.367850] ? rcu_do_batch+0x1e6/0x5e0 [ 107.368148] aa_free_profile+0x23/0x60 [ 107.368438] label_free_switch+0x4c/0x80 [ 107.368751] label_free_rcu+0x1c/0x50 [ 107.369038] rcu_do_batch+0x1e8/0x5e0 [ 107.369324] ? rcu_do_batch+0x157/0x5e0 [ 107.369626] rcu_core+0x1b0/0x2f0 [ 107.369888] rcu_core_si+0xe/0x20 [ 107.370156] handle_softirqs+0x9b/0x3d0 [ 107.370460] ? smpboot_thread_fn+0x26/0x210 [ 107.370790] run_ksoftirqd+0x3a/0x70 [ 107.371070] smpboot_thread_fn+0xf9/0x210 [ 107.371383] ? __pfx_smpboot_thread_fn+0x10/0x10 [ 107.371746] kthread+0x10d/0x280 [ 107.372010] ? __pfx_kthread+0x10/0x10 [ 107.372310] ret_from_fork+0x44/0x70 [ 107.372655] ? __pfx_kthread+0x10/0x10 [ 107.372974] ret_from_fork_asm+0x1a/0x30 [ 107.373316] </TASK> [ 107.373505] Modules linked in: af_packet_diag mptcp_diag tcp_diag udp_diag raw_diag inet_diag snd_seq_dummy snd_hrtimer snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer snd soundcore qrtr binfmt_misc intel_rapl_msr intel_rapl_common kvm_amd ccp kvm irqbypass polyval_clmulni polyval_generic ghash_clmulni_intel sha256_ssse3 sha1_ssse3 aesni_intel crypto_simd cryptd i2c_piix4 i2c_smbus input_leds joydev sch_fq_codel msr parport_pc ppdev lp parport efi_pstore nfnetlink vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vsock vmw_vmci dmi_sysfs qemu_fw_cfg ip_tables x_tables autofs4 hid_generic usbhid hid psmouse serio_raw floppy bochs pata_acpi [ 107.379086] ---[ end trace 0000000000000000 ]--- Don't set the count until a ruleset is actually allocated and guard against free_ruleset() being called with a null pointer. Reported-by: Ryan Lee <ryan.lee@canonical.com> Fixes: 217af7e ("apparmor: refactor profile rules and attachments") Signed-off-by: John Johansen <john.johansen@canonical.com>

benet crashes as soon as SRIOV VFs are created: kernel BUG at mm/vmalloc.c:3457! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 4 UID: 0 PID: 7408 Comm: test.sh Kdump: loaded Not tainted 6.16.0+ #1 PREEMPT(voluntary) [...] RIP: 0010:vunmap+0x5f/0x70 [...] Call Trace: <TASK> __iommu_dma_free+0xe8/0x1c0 be_cmd_set_mac_list+0x3fe/0x640 [be2net] be_cmd_set_mac+0xaf/0x110 [be2net] be_vf_eth_addr_config+0x19f/0x330 [be2net] be_vf_setup+0x4f7/0x990 [be2net] be_pci_sriov_configure+0x3a1/0x470 [be2net] sriov_numvfs_store+0x20b/0x380 kernfs_fop_write_iter+0x354/0x530 vfs_write+0x9b9/0xf60 ksys_write+0xf3/0x1d0 do_syscall_64+0x8c/0x3d0 be_cmd_set_mac_list() calls dma_free_coherent() under a spin_lock_bh. Fix it by freeing only after the lock has been released. Fixes: 1a82d19 ("be2net: fix sleeping while atomic bugs in be_ndo_bridge_getlink") Signed-off-by: Michal Schmidt <mschmidt@redhat.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20250801101338.72502-1-mschmidt@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

A kernel panic can be triggered by reading /proc/fs/cifs/debug_dirs. The crash is a null-ptr-deref inside spin_lock(), caused by the use of the uninitialized global spinlock cifs_tcp_ses_lock. init_cifs() └── cifs_proc_init() └── // User can access /proc/fs/cifs/debug_dirs here └── cifs_debug_dirs_proc_show() └── spin_lock(&cifs_tcp_ses_lock); // Uninitialized! KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] Mem abort info: ESR = 0x0000000096000005 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x05: level 1 translation fault Data abort info: ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [dfff800000000000] address between user and kernel address ranges Internal error: Oops: 0000000096000005 [#1] SMP Modules linked in: CPU: 3 UID: 0 PID: 16435 Comm: stress-ng-procf Not tainted 6.16.0-10385-g79f14b5d84c6 torvalds#37 PREEMPT Hardware name: QEMU KVM Virtual Machine, BIOS 2025.02-8ubuntu1 06/11/2025 pstate: 23400005 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : do_raw_spin_lock+0x84/0x2cc lr : _raw_spin_lock+0x24/0x34 sp : ffff8000966477e0 x29: ffff800096647860 x28: ffff800096647b88 x27: ffff0001c0c22070 x26: ffff0003eb2b60c8 x25: ffff0001c0c22018 x24: dfff800000000000 x23: ffff0000f624e000 x22: ffff0003eb2b6020 x21: ffff0000f624e768 x20: 0000000000000004 x19: 0000000000000000 x18: 0000000000000000 x17: 0000000000000000 x16: ffff8000804b9600 x15: ffff700012cc8f04 x14: 1ffff00012cc8f04 x13: 0000000000000004 x12: ffffffffffffffff x11: 1ffff00012cc8f00 x10: ffff80008d9af0d2 x9 : f3f3f304f1f1f1f1 x8 : 0000000000000000 x7 : 7365733c203e6469 x6 : 20656572743c2023 x5 : ffff0000e0ce0044 x4 : ffff80008a4deb6e x3 : ffff8000804b9718 x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: do_raw_spin_lock+0x84/0x2cc (P) _raw_spin_lock+0x24/0x34 cifs_debug_dirs_proc_show+0x1ac/0x4c0 seq_read_iter+0x3b0/0xc28 proc_reg_read_iter+0x178/0x2a8 vfs_read+0x5f8/0x88c ksys_read+0x120/0x210 __arm64_sys_read+0x7c/0x90 invoke_syscall+0x98/0x2b8 el0_svc_common+0x130/0x23c do_el0_svc+0x48/0x58 el0_svc+0x40/0x140 el0t_64_sync_handler+0x84/0x12c el0t_64_sync+0x1ac/0x1b0 Code: aa0003f3 f9000feb f2fe7e69 f8386969 (38f86908) ---[ end trace 0000000000000000 ]--- The root cause is an initialization order problem. The lock is declared as a global variable and intended to be initialized during module startup. However, the procfs entry that uses this lock can be accessed by userspace before the spin_lock_init() call has run. This creates a race window where reading the proc file will attempt to use the lock before it is initialized, leading to the crash. For a global lock with a static lifetime, the correct and robust approach is to use compile-time initialization. Fixes: 844e5c0 ("smb3 client: add way to show directory leases for improved debugging") Signed-off-by: Yunseong Kim <ysk@kzalloc.com> Signed-off-by: Steve French <stfrench@microsoft.com>

I accidentally added a bug in pptp_xmit() that syzbot caught for us. Only call ip_rt_put() if a route has been allocated. BUG: unable to handle page fault for address: ffffffffffffffdb PGD df3b067 P4D df3b067 PUD df3d067 PMD 0 Oops: Oops: 0002 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 6346 Comm: syz.0.336 Not tainted 6.16.0-next-20250804-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:85 [inline] RIP: 0010:raw_atomic_sub_return_release include/linux/atomic/atomic-arch-fallback.h:846 [inline] RIP: 0010:atomic_sub_return_release include/linux/atomic/atomic-instrumented.h:327 [inline] RIP: 0010:__rcuref_put include/linux/rcuref.h:109 [inline] RIP: 0010:rcuref_put+0x172/0x210 include/linux/rcuref.h:173 Call Trace: <TASK> dst_release+0x24/0x1b0 net/core/dst.c:167 ip_rt_put include/net/route.h:285 [inline] pptp_xmit+0x14b/0x1a90 drivers/net/ppp/pptp.c:267 __ppp_channel_push+0xf2/0x1c0 drivers/net/ppp/ppp_generic.c:2166 ppp_channel_push+0x123/0x660 drivers/net/ppp/ppp_generic.c:2198 ppp_write+0x2b0/0x400 drivers/net/ppp/ppp_generic.c:544 vfs_write+0x27b/0xb30 fs/read_write.c:684 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: de9c486 ("pptp: ensure minimal skb length in pptp_xmit()") Reported-by: syzbot+27d7cfbc93457e472e00@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/689095a5.050a0220.1fc43d.0009.GAE@google.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250807142146.2877060-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

There is a potential deadlock that can happen in try_release_subpage_extent_buffer() because the irq-safe xarray spin lock fs_info->buffer_tree is being acquired before the irq-unsafe eb->refs_lock. This leads to the potential race: // T1 (random eb->refs user) // T2 (release folio) spin_lock(&eb->refs_lock); // interrupt end_bbio_meta_write() btrfs_meta_folio_clear_writeback() btree_release_folio() folio_test_writeback() //false try_release_extent_buffer() try_release_subpage_extent_buffer() xa_lock_irq(&fs_info->buffer_tree) spin_lock(&eb->refs_lock); // blocked; held by T1 buffer_tree_clear_mark() xas_lock_irqsave() // blocked; held by T2 I believe that the spin lock can safely be replaced by an rcu_read_lock. The xa_for_each loop does not need the spin lock as it's already internally protected by the rcu_read_lock. The extent buffer is also protected by the rcu_read_lock so it won't be freed before we take the eb->refs_lock and check the ref count. The rcu_read_lock is taken and released every iteration, just like the spin lock, which means we're not protected against concurrent insertions into the xarray. This is fine because we rely on folio->private to detect if there are any ebs remaining in the folio. There is already some precedent for this with find_extent_buffer_nolock, which loads an extent buffer from the xarray with only rcu_read_lock. lockdep warning: ===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 6.16.0-0_fbk701_debug_rc0_123_g4c06e63b9203 #1 Tainted: G E N ----------------------------------------------------- kswapd0/66 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff000011ffd600 (&eb->refs_lock){+.+.}-{3:3}, at: try_release_extent_buffer+0x18c/0x560 and this task is already holding: ffff0000c1d91b88 (&buffer_xa_class){-.-.}-{3:3}, at: try_release_extent_buffer+0x13c/0x560 which would create a new lock dependency: (&buffer_xa_class){-.-.}-{3:3} -> (&eb->refs_lock){+.+.}-{3:3} but this new dependency connects a HARDIRQ-irq-safe lock: (&buffer_xa_class){-.-.}-{3:3} ... which became HARDIRQ-irq-safe at: lock_acquire+0x178/0x358 _raw_spin_lock_irqsave+0x60/0x88 buffer_tree_clear_mark+0xc4/0x160 end_bbio_meta_write+0x238/0x398 btrfs_bio_end_io+0x1f8/0x330 btrfs_orig_write_end_io+0x1c4/0x2c0 bio_endio+0x63c/0x678 blk_update_request+0x1c4/0xa00 blk_mq_end_request+0x54/0x88 virtblk_request_done+0x124/0x1d0 blk_mq_complete_request+0x84/0xa0 virtblk_done+0x130/0x238 vring_interrupt+0x130/0x288 __handle_irq_event_percpu+0x1e8/0x708 handle_irq_event+0x98/0x1b0 handle_fasteoi_irq+0x264/0x7c0 generic_handle_domain_irq+0xa4/0x108 gic_handle_irq+0x7c/0x1a0 do_interrupt_handler+0xe4/0x148 el1_interrupt+0x30/0x50 el1h_64_irq_handler+0x14/0x20 el1h_64_irq+0x6c/0x70 _raw_spin_unlock_irq+0x38/0x70 __run_timer_base+0xdc/0x5e0 run_timer_softirq+0xa0/0x138 handle_softirqs.llvm.13542289750107964195+0x32c/0xbd0 ____do_softirq.llvm.17674514681856217165+0x18/0x28 call_on_irq_stack+0x24/0x30 __irq_exit_rcu+0x164/0x430 irq_exit_rcu+0x18/0x88 el1_interrupt+0x34/0x50 el1h_64_irq_handler+0x14/0x20 el1h_64_irq+0x6c/0x70 arch_local_irq_enable+0x4/0x8 do_idle+0x1a0/0x3b8 cpu_startup_entry+0x60/0x80 rest_init+0x204/0x228 start_kernel+0x394/0x3f0 __primary_switched+0x8c/0x8958 to a HARDIRQ-irq-unsafe lock: (&eb->refs_lock){+.+.}-{3:3} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x178/0x358 _raw_spin_lock+0x4c/0x68 free_extent_buffer_stale+0x2c/0x170 btrfs_read_sys_array+0x1b0/0x338 open_ctree+0xeb0/0x1df8 btrfs_get_tree+0xb60/0x1110 vfs_get_tree+0x8c/0x250 fc_mount+0x20/0x98 btrfs_get_tree+0x4a4/0x1110 vfs_get_tree+0x8c/0x250 do_new_mount+0x1e0/0x6c0 path_mount+0x4ec/0xa58 __arm64_sys_mount+0x370/0x490 invoke_syscall+0x6c/0x208 el0_svc_common+0x14c/0x1b8 do_el0_svc+0x4c/0x60 el0_svc+0x4c/0x160 el0t_64_sync_handler+0x70/0x100 el0t_64_sync+0x168/0x170 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&eb->refs_lock); local_irq_disable(); lock(&buffer_xa_class); lock(&eb->refs_lock); <Interrupt> lock(&buffer_xa_class); *** DEADLOCK *** 2 locks held by kswapd0/66: #0: ffff800085506e40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xe8/0xe50 #1: ffff0000c1d91b88 (&buffer_xa_class){-.-.}-{3:3}, at: try_release_extent_buffer+0x13c/0x560 Link: https://www.kernel.org/doc/Documentation/locking/lockdep-design.rst#:~:text=Multi%2Dlock%20dependency%20rules%3A Fixes: 19d7f65 ("btrfs: convert the buffer_radix to an xarray") CC: stable@vger.kernel.org # 6.16+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Leo Martins <loemra.dev@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>

The check_pmd_still_valid() call during collapse is currently only protected by the mmap_lock in write mode, which was sufficient when pt_reclaim always ran under mmap_lock in read mode. However, since madvise_dontneed can now execute under a per-VMA lock, this assumption is no longer valid. As a result, a race condition can occur between collapse and PT_RECLAIM, potentially leading to a kernel panic. [ 38.151897] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] SMP KASI [ 38.153519] KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] [ 38.154605] CPU: 0 UID: 0 PID: 721 Comm: repro Not tainted 6.16.0-next-20250801-next-2025080 #1 PREEMPT(voluntary) [ 38.155929] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org4 [ 38.157418] RIP: 0010:kasan_byte_accessible+0x15/0x30 [ 38.158125] Code: 03 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 b8 00 00 00 00 00 fc0 [ 38.160461] RSP: 0018:ffff88800feef678 EFLAGS: 00010286 [ 38.161220] RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 1ffffffff0dde60c [ 38.162232] RDX: 0000000000000000 RSI: ffffffff85da1e18 RDI: dffffc0000000003 [ 38.163176] RBP: ffff88800feef698 R08: 0000000000000001 R09: 0000000000000000 [ 38.164195] R10: 0000000000000000 R11: ffff888016a8ba58 R12: 0000000000000018 [ 38.165189] R13: 0000000000000018 R14: ffffffff85da1e18 R15: 0000000000000000 [ 38.166100] FS: 0000000000000000(0000) GS:ffff8880e3b40000(0000) knlGS:0000000000000000 [ 38.167137] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 38.167891] CR2: 00007f97fadfe504 CR3: 0000000007088005 CR4: 0000000000770ef0 [ 38.168812] PKRU: 55555554 [ 38.169275] Call Trace: [ 38.169647] <TASK> [ 38.169975] ? __kasan_check_byte+0x19/0x50 [ 38.170581] lock_acquire+0xea/0x310 [ 38.171083] ? rcu_is_watching+0x19/0xc0 [ 38.171615] ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20 [ 38.172343] ? __sanitizer_cov_trace_const_cmp8+0x1c/0x30 [ 38.173130] _raw_spin_lock+0x38/0x50 [ 38.173707] ? __pte_offset_map_lock+0x1a2/0x3c0 [ 38.174390] __pte_offset_map_lock+0x1a2/0x3c0 [ 38.174987] ? __pfx___pte_offset_map_lock+0x10/0x10 [ 38.175724] ? __pfx_pud_val+0x10/0x10 [ 38.176308] ? __sanitizer_cov_trace_const_cmp1+0x1e/0x30 [ 38.177183] unmap_page_range+0xb60/0x43e0 [ 38.177824] ? __pfx_unmap_page_range+0x10/0x10 [ 38.178485] ? mas_next_slot+0x133a/0x1a50 [ 38.179079] unmap_single_vma.constprop.0+0x15b/0x250 [ 38.179830] unmap_vmas+0x1fa/0x460 [ 38.180373] ? __pfx_unmap_vmas+0x10/0x10 [ 38.180994] ? __sanitizer_cov_trace_const_cmp4+0x1a/0x20 [ 38.181877] exit_mmap+0x1a2/0xb40 [ 38.182396] ? lock_release+0x14f/0x2c0 [ 38.182929] ? __pfx_exit_mmap+0x10/0x10 [ 38.183474] ? __pfx___mutex_unlock_slowpath+0x10/0x10 [ 38.184188] ? mutex_unlock+0x16/0x20 [ 38.184704] mmput+0x132/0x370 [ 38.185208] do_exit+0x7e7/0x28c0 [ 38.185682] ? __this_cpu_preempt_check+0x21/0x30 [ 38.186328] ? do_group_exit+0x1d8/0x2c0 [ 38.186873] ? __pfx_do_exit+0x10/0x10 [ 38.187401] ? __this_cpu_preempt_check+0x21/0x30 [ 38.188036] ? _raw_spin_unlock_irq+0x2c/0x60 [ 38.188634] ? lockdep_hardirqs_on+0x89/0x110 [ 38.189313] do_group_exit+0xe4/0x2c0 [ 38.189831] __x64_sys_exit_group+0x4d/0x60 [ 38.190413] x64_sys_call+0x2174/0x2180 [ 38.190935] do_syscall_64+0x6d/0x2e0 [ 38.191449] entry_SYSCALL_64_after_hwframe+0x76/0x7e This patch moves the vma_start_write() call to precede check_pmd_still_valid(), ensuring that the check is also properly protected by the per-VMA lock. Link: https://lkml.kernel.org/r/20250805035447.7958-1-21cnbao@gmail.com Fixes: a6fde7a ("mm: use per_vma lock for MADV_DONTNEED") Signed-off-by: Barry Song <v-songbaohua@oppo.com> Tested-by: "Lai, Yi" <yi1.lai@linux.intel.com> Reported-by: "Lai, Yi" <yi1.lai@linux.intel.com> Closes: https://lore.kernel.org/all/aJAFrYfyzGpbm+0m@ly-workstation/ Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Lokesh Gidra <lokeshgidra@google.com> Cc: Tangquan Zheng <zhengtangquan@oppo.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Nico Pache <npache@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Dev Jain <dev.jain@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Since EROFS handles decompression in non-atomic contexts due to uncontrollable decompression latencies and vmap() usage, it tries to detect atomic contexts and only kicks off a kworker on demand in order to reduce unnecessary scheduling overhead. However, the current approach is insufficient and can lead to sleeping function calls in invalid contexts, causing kernel warnings and potential system instability. See the stacktrace [1] and previous discussion [2]. The current implementation only checks rcu_read_lock_any_held(), which behaves inconsistently across different kernel configurations: - When CONFIG_DEBUG_LOCK_ALLOC is enabled: correctly detects RCU critical sections by checking rcu_lock_map - When CONFIG_DEBUG_LOCK_ALLOC is disabled: compiles to "!preemptible()", which only checks preempt_count and misses RCU critical sections This patch introduces z_erofs_in_atomic() to provide comprehensive atomic context detection: 1. Check RCU preemption depth when CONFIG_PREEMPTION is enabled, as RCU critical sections may not affect preempt_count but still require atomic handling 2. Always use async processing when CONFIG_PREEMPT_COUNT is disabled, as preemption state cannot be reliably determined 3. Fall back to standard preemptible() check for remaining cases The function replaces the previous complex condition check and ensures that z_erofs always uses (kthread_)work in atomic contexts to minimize scheduling overhead and prevent sleeping in invalid contexts. [1] Problem stacktrace [ 61.266692] BUG: sleeping function called from invalid context at kernel/locking/rtmutex_api.c:510 [ 61.266702] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 107, name: irq/54-ufshcd [ 61.266704] preempt_count: 0, expected: 0 [ 61.266705] RCU nest depth: 2, expected: 0 [ 61.266710] CPU: 0 UID: 0 PID: 107 Comm: irq/54-ufshcd Tainted: G W O 6.12.17 #1 [ 61.266714] Tainted: [W]=WARN, [O]=OOT_MODULE [ 61.266715] Hardware name: schumacher (DT) [ 61.266717] Call trace: [ 61.266718] dump_backtrace+0x9c/0x100 [ 61.266727] show_stack+0x20/0x38 [ 61.266728] dump_stack_lvl+0x78/0x90 [ 61.266734] dump_stack+0x18/0x28 [ 61.266736] __might_resched+0x11c/0x180 [ 61.266743] __might_sleep+0x64/0xc8 [ 61.266745] mutex_lock+0x2c/0xc0 [ 61.266748] z_erofs_decompress_queue+0xe8/0x978 [ 61.266753] z_erofs_decompress_kickoff+0xa8/0x190 [ 61.266756] z_erofs_endio+0x168/0x288 [ 61.266758] bio_endio+0x160/0x218 [ 61.266762] blk_update_request+0x244/0x458 [ 61.266766] scsi_end_request+0x38/0x278 [ 61.266770] scsi_io_completion+0x4c/0x600 [ 61.266772] scsi_finish_command+0xc8/0xe8 [ 61.266775] scsi_complete+0x88/0x148 [ 61.266777] blk_mq_complete_request+0x3c/0x58 [ 61.266780] scsi_done_internal+0xcc/0x158 [ 61.266782] scsi_done+0x1c/0x30 [ 61.266783] ufshcd_compl_one_cqe+0x12c/0x438 [ 61.266786] __ufshcd_transfer_req_compl+0x2c/0x78 [ 61.266788] ufshcd_poll+0xf4/0x210 [ 61.266789] ufshcd_transfer_req_compl+0x50/0x88 [ 61.266791] ufshcd_intr+0x21c/0x7c8 [ 61.266792] irq_forced_thread_fn+0x44/0xd8 [ 61.266796] irq_thread+0x1a4/0x358 [ 61.266799] kthread+0x12c/0x138 [ 61.266802] ret_from_fork+0x10/0x20 [2] https://lore.kernel.org/r/58b661d0-0ebb-4b45-a10d-c5927fb791cd@paulmck-laptop Signed-off-by: Junli Liu <liujunli@lixiang.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20250805011957.911186-1-liujunli@lixiang.com [ Gao Xiang: Use the original trace in v1. ] Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

The existing code move the VF NIC to new namespace when NETDEV_REGISTER is received on netvsc NIC. During deletion of the namespace, default_device_exit_batch() >> default_device_exit_net() is called. When netvsc NIC is moved back and registered to the default namespace, it automatically brings VF NIC back to the default namespace. This will cause the default_device_exit_net() >> for_each_netdev_safe loop unable to detect the list end, and hit NULL ptr: [ 231.449420] mana 7870:00:00.0 enP30832s1: Moved VF to namespace with: eth0 [ 231.449656] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 231.450246] #PF: supervisor read access in kernel mode [ 231.450579] #PF: error_code(0x0000) - not-present page [ 231.450916] PGD 17b8a8067 P4D 0 [ 231.451163] Oops: Oops: 0000 [#1] SMP NOPTI [ 231.451450] CPU: 82 UID: 0 PID: 1394 Comm: kworker/u768:1 Not tainted 6.16.0-rc4+ #3 VOLUNTARY [ 231.452042] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024 [ 231.452692] Workqueue: netns cleanup_net [ 231.452947] RIP: 0010:default_device_exit_batch+0x16c/0x3f0 [ 231.453326] Code: c0 0c f5 b3 e8 d5 db fe ff 48 85 c0 74 15 48 c7 c2 f8 fd ca b2 be 10 00 00 00 48 8d 7d c0 e8 7b 77 25 00 49 8b 86 28 01 00 00 <48> 8b 50 10 4c 8b 2a 4c 8d 62 f0 49 83 ed 10 4c 39 e0 0f 84 d6 00 [ 231.454294] RSP: 0018:ff75fc7c9bf9fd00 EFLAGS: 00010246 [ 231.454610] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 61c8864680b583eb [ 231.455094] RDX: ff1fa9f71462d800 RSI: ff75fc7c9bf9fd38 RDI: 0000000030766564 [ 231.455686] RBP: ff75fc7c9bf9fd78 R08: 0000000000000000 R09: 0000000000000000 [ 231.456126] R10: 0000000000000001 R11: 0000000000000004 R12: ff1fa9f70088e340 [ 231.456621] R13: ff1fa9f70088e340 R14: ffffffffb3f50c20 R15: ff1fa9f7103e6340 [ 231.457161] FS: 0000000000000000(0000) GS:ff1faa6783a08000(0000) knlGS:0000000000000000 [ 231.457707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.458031] CR2: 0000000000000010 CR3: 0000000179ab2006 CR4: 0000000000b73ef0 [ 231.458434] Call Trace: [ 231.458600] <TASK> [ 231.458777] ops_undo_list+0x100/0x220 [ 231.459015] cleanup_net+0x1b8/0x300 [ 231.459285] process_one_work+0x184/0x340 To fix it, move the ns change to a workqueue, and take rtnl_lock to avoid changing the netdev list when default_device_exit_net() is using it. Cc: stable@vger.kernel.org Fixes: 4c26280 ("hv_netvsc: Fix VF namespace also in synthetic NIC NETDEV_REGISTER event") Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Link: https://patch.msgid.link/1754511711-11188-1-git-send-email-haiyangz@linux.microsoft.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

syzbot reported the splat below. [0] When nsim_queue_uninit() is called from nsim_init_netdevsim(), register_netdevice() has not been called, thus dev->dstats has not been allocated. Let's not call dev_dstats_rx_dropped_add() in such a case. [0] BUG: unable to handle page fault for address: ffff88809782c020 PF: supervisor write access in kernel mode PF: error_code(0x0002) - not-present page PGD 1b401067 P4D 1b401067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN NOPTI CPU: 3 UID: 0 PID: 8476 Comm: syz.1.251 Not tainted 6.16.0-syzkaller-06699-ge8d780dcd957 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:local_add arch/x86/include/asm/local.h:33 [inline] RIP: 0010:u64_stats_add include/linux/u64_stats_sync.h:89 [inline] RIP: 0010:dev_dstats_rx_dropped_add include/linux/netdevice.h:3027 [inline] RIP: 0010:nsim_queue_free+0xba/0x120 drivers/net/netdevsim/netdev.c:714 Code: 07 77 6c 4a 8d 3c ed 20 7e f1 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 46 4a 03 1c ed 20 7e f1 8d <4c> 01 63 20 be 00 02 00 00 48 8d 3d 00 00 00 00 e8 61 2f 58 fa 48 RSP: 0018:ffffc900044af150 EFLAGS: 00010286 RAX: dffffc0000000000 RBX: ffff88809782c000 RCX: 00000000000079c3 RDX: 1ffffffff1be2fc7 RSI: ffffffff8c15f380 RDI: ffffffff8df17e38 RBP: ffff88805f59d000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000003 R14: ffff88806ceb3d00 R15: ffffed100dfd308e FS: 0000000000000000(0000) GS:ffff88809782c000(0063) knlGS:00000000f505db40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: ffff88809782c020 CR3: 000000006fc6a000 CR4: 0000000000352ef0 Call Trace: <TASK> nsim_queue_uninit drivers/net/netdevsim/netdev.c:993 [inline] nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline] nsim_create+0xd0a/0x1260 drivers/net/netdevsim/netdev.c:1101 __nsim_dev_port_add+0x435/0x7d0 drivers/net/netdevsim/dev.c:1438 nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1494 [inline] nsim_dev_reload_create drivers/net/netdevsim/dev.c:1546 [inline] nsim_dev_reload_up+0x5b8/0x860 drivers/net/netdevsim/dev.c:1003 devlink_reload+0x322/0x7c0 net/devlink/dev.c:474 devlink_nl_reload_doit+0xe31/0x1410 net/devlink/dev.c:584 genl_family_rcv_msg_doit+0x206/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg net/socket.c:729 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2614 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668 __sys_sendmsg+0x16d/0x220 net/socket.c:2700 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf708e579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f505d55c EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 0000000080000080 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: CR2: ffff88809782c020 Fixes: 2a68a22 ("netdevsim: account dropped packet length in stats on queue free") Reported-by: syzbot+8aa80c6232008f7b957d@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/688bb9ca.a00a0220.26d0e1.0050.GAE@google.com/ Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250812162130.4129322-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Shuang reported sch_ets test-case [1] crashing in ets_class_qlen_notify() after recent changes from Lion [2]. The problem is: in ets_qdisc_change() we purge unused DWRR queues; the value of 'q->nbands' is the new one, and the cleanup should be done with the old one. The problem is here since my first attempts to fix ets_qdisc_change(), but it surfaced again after the recent qdisc len accounting fixes. Fix it purging idle DWRR queues before assigning a new value of 'q->nbands', so that all purge operations find a consistent configuration: - old 'q->nbands' because it's needed by ets_class_find() - old 'q->nstrict' because it's needed by ets_class_is_strict() BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 62 UID: 0 PID: 39457 Comm: tc Kdump: loaded Not tainted 6.12.0-116.el10.x86_64 #1 PREEMPT(voluntary) Hardware name: Dell Inc. PowerEdge R640/06DKY5, BIOS 2.12.2 07/09/2021 RIP: 0010:__list_del_entry_valid_or_report+0x4/0x80 Code: ff 4c 39 c7 0f 84 39 19 8e ff b8 01 00 00 00 c3 cc cc cc cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> 8b 17 48 8b 4f 08 48 85 d2 0f 84 56 19 8e ff 48 85 c9 0f 84 ab RSP: 0018:ffffba186009f400 EFLAGS: 00010202 RAX: 00000000000000d6 RBX: 0000000000000000 RCX: 0000000000000004 RDX: ffff9f0fa29b69c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffffc12c2400 R08: 0000000000000008 R09: 0000000000000004 R10: ffffffffffffffff R11: 0000000000000004 R12: 0000000000000000 R13: ffff9f0f8cfe0000 R14: 0000000000100005 R15: 0000000000000000 FS: 00007f2154f37480(0000) GS:ffff9f269c1c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000001530be001 CR4: 00000000007726f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ets_class_qlen_notify+0x65/0x90 [sch_ets] qdisc_tree_reduce_backlog+0x74/0x110 ets_qdisc_change+0x630/0xa40 [sch_ets] __tc_modify_qdisc.constprop.0+0x216/0x7f0 tc_modify_qdisc+0x7c/0x120 rtnetlink_rcv_msg+0x145/0x3f0 netlink_rcv_skb+0x53/0x100 netlink_unicast+0x245/0x390 netlink_sendmsg+0x21b/0x470 ____sys_sendmsg+0x39d/0x3d0 ___sys_sendmsg+0x9a/0xe0 __sys_sendmsg+0x7a/0xd0 do_syscall_64+0x7d/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f2155114084 Code: 89 02 b8 ff ff ff ff eb bb 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 80 3d 25 f0 0c 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 89 54 24 1c 48 89 RSP: 002b:00007fff1fd7a988 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000560ec063e5e0 RCX: 00007f2155114084 RDX: 0000000000000000 RSI: 00007fff1fd7a9f0 RDI: 0000000000000003 RBP: 00007fff1fd7aa60 R08: 0000000000000010 R09: 000000000000003f R10: 0000560ee9b3a010 R11: 0000000000000202 R12: 00007fff1fd7aae0 R13: 000000006891ccde R14: 0000560ec063e5e0 R15: 00007fff1fd7aad0 </TASK> [1] https://lore.kernel.org/netdev/e08c7f4a6882f260011909a868311c6e9b54f3e4.1639153474.git.dcaratti@redhat.com/ [2] https://lore.kernel.org/netdev/d912cbd7-193b-4269-9857-525bee8bbb6a@gmail.com/ Cc: stable@vger.kernel.org Fixes: 103406b ("net/sched: Always pass notifications when child class becomes empty") Fixes: c062f2a ("net/sched: sch_ets: don't remove idle classes from the round-robin list") Fixes: dcc68b4 ("net: sch_ets: Add a new Qdisc") Reported-by: Li Shuang <shuali@redhat.com> Closes: https://issues.redhat.com/browse/RHEL-108026 Reviewed-by: Petr Machata <petrm@nvidia.com> Co-developed-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: Ivan Vecera <ivecera@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Link: https://patch.msgid.link/7928ff6d17db47a2ae7cc205c44777b1f1950545.1755016081.git.dcaratti@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

btrfs_subpage_set_writeback() calls folio_start_writeback() the first time a folio is written back, and it also clears the PAGECACHE_TAG_TOWRITE tag even if there are still dirty blocks in the folio. This can break ordering guarantees, such as those required by btrfs_wait_ordered_extents(). That ordering breakage leads to a real failure. For example, running generic/464 on a zoned setup will hit the following ASSERT. This happens because the broken ordering fails to flush existing dirty pages before the file size is truncated. assertion failed: !list_empty(&ordered->list) :: 0, in fs/btrfs/zoned.c:1899 ------------[ cut here ]------------ kernel BUG at fs/btrfs/zoned.c:1899! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 1906169 Comm: kworker/u130:2 Kdump: loaded Not tainted 6.16.0-rc6-BTRFS-ZNS+ torvalds#554 PREEMPT(voluntary) Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021 Workqueue: btrfs-endio-write btrfs_work_helper [btrfs] RIP: 0010:btrfs_finish_ordered_zoned.cold+0x50/0x52 [btrfs] RSP: 0018:ffffc9002efdbd60 EFLAGS: 00010246 RAX: 000000000000004c RBX: ffff88811923c4e0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff827e38b1 RDI: 00000000ffffffff RBP: ffff88810005d000 R08: 00000000ffffdfff R09: ffffffff831051c8 R10: ffffffff83055220 R11: 0000000000000000 R12: ffff8881c2458c00 R13: ffff88811923c540 R14: ffff88811923c5e8 R15: ffff8881c1bd9680 FS: 0000000000000000(0000) GS:ffff88a04acd0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f907c7a918c CR3: 0000000004024000 CR4: 0000000000350ef0 Call Trace: <TASK> ? srso_return_thunk+0x5/0x5f btrfs_finish_ordered_io+0x4a/0x60 [btrfs] btrfs_work_helper+0xf9/0x490 [btrfs] process_one_work+0x204/0x590 ? srso_return_thunk+0x5/0x5f worker_thread+0x1d6/0x3d0 ? __pfx_worker_thread+0x10/0x10 kthread+0x118/0x230 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x205/0x260 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Consider process A calling writepages() with WB_SYNC_NONE. In zoned mode or for compressed writes, it locks several folios for delalloc and starts writing them out. Let's call the last locked folio folio X. Suppose the write range only partially covers folio X, leaving some pages dirty. Process A calls btrfs_subpage_set_writeback() when building a bio. This function call clears the TOWRITE tag of folio X, whose size = 8K and the block size = 4K. It is following state. 0 4K 8K |/////|/////| (flag: DIRTY, tag: DIRTY) <-----> Process A will write this range. Now suppose process B concurrently calls writepages() with WB_SYNC_ALL. It calls tag_pages_for_writeback() to tag dirty folios with PAGECACHE_TAG_TOWRITE. Since folio X is still dirty, it gets tagged. Then, B collects tagged folios using filemap_get_folios_tag() and must wait for folio X to be written before returning from writepages(). 0 4K 8K |/////|/////| (flag: DIRTY, tag: DIRTY|TOWRITE) However, between tagging and collecting, process A may call btrfs_subpage_set_writeback() and clear folio X's TOWRITE tag. 0 4K 8K | |/////| (flag: DIRTY|WRITEBACK, tag: DIRTY) As a result, process B won't see folio X in its batch, and returns without waiting for it. This breaks the WB_SYNC_ALL ordering requirement. Fix this by using btrfs_subpage_set_writeback_keepwrite(), which retains the TOWRITE tag. We now manually clear the tag only after the folio becomes clean, via the xas operation. Fixes: 3470da3 ("btrfs: subpage: introduce helpers for writeback status") CC: stable@vger.kernel.org # 6.12+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>

An use-after-free issue occurred when __mark_inode_dirty() get the bdi_writeback that was in the progress of switching. CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1 ...... pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __mark_inode_dirty+0x124/0x418 lr : __mark_inode_dirty+0x118/0x418 sp : ffffffc08c9dbbc0 ........ Call trace: __mark_inode_dirty+0x124/0x418 generic_update_time+0x4c/0x60 file_modified+0xcc/0xd0 ext4_buffered_write_iter+0x58/0x124 ext4_file_write_iter+0x54/0x704 vfs_write+0x1c0/0x308 ksys_write+0x74/0x10c __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x40/0xe4 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x194/0x198 Root cause is: systemd-random-seed kworker ---------------------------------------------------------------------- ___mark_inode_dirty inode_switch_wbs_work_fn spin_lock(&inode->i_lock); inode_attach_wb locked_inode_to_wb_and_lock_list get inode->i_wb spin_unlock(&inode->i_lock); spin_lock(&wb->list_lock) spin_lock(&inode->i_lock) inode_io_list_move_locked spin_unlock(&wb->list_lock) spin_unlock(&inode->i_lock) spin_lock(&old_wb->list_lock) inode_do_switch_wbs spin_lock(&inode->i_lock) inode->i_wb = new_wb spin_unlock(&inode->i_lock) spin_unlock(&old_wb->list_lock) wb_put_many(old_wb, nr_switched) cgwb_release old wb released wb_wakeup_delayed() accesses wb, then trigger the use-after-free issue Fix this race condition by holding inode spinlock until wb_wakeup_delayed() finished. Signed-off-by: Jiufei Xue <jiufei.xue@samsung.com> Link: https://lore.kernel.org/20250728100715.3863241-1-jiufei.xue@samsung.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>

…dlock When a user creates a dualpi2 qdisc it automatically sets a timer. This timer will run constantly and update the qdisc's probability field. The issue is that the timer acquires the qdisc root lock and runs in hardirq. The qdisc root lock is also acquired in dev.c whenever a packet arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq, it may interrupt the packet processing running in softirq. If that happens and it runs on the same CPU, it will acquire the same lock and cause a deadlock. The following splat shows up when running a kernel compiled with lock debugging: [ +0.000224] WARNING: inconsistent lock state [ +0.000224] 6.16.0+ #10 Not tainted [ +0.000169] -------------------------------- [ +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. [ +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes: [ +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140 [ +0.000000] {IN-HARDIRQ-W} state was registered at: [ +0.000000] lock_acquire.part.0+0xb6/0x220 [ +0.000000] _raw_spin_lock+0x31/0x80 [ +0.000000] dualpi2_timer+0x6f/0x270 [ +0.000000] __hrtimer_run_queues+0x1c5/0x360 [ +0.000000] hrtimer_interrupt+0x115/0x260 [ +0.000000] __sysvec_apic_timer_interrupt+0x6d/0x1a0 [ +0.000000] sysvec_apic_timer_interrupt+0x6e/0x80 [ +0.000000] asm_sysvec_apic_timer_interrupt+0x1a/0x20 [ +0.000000] pv_native_safe_halt+0xf/0x20 [ +0.000000] default_idle+0x9/0x10 [ +0.000000] default_idle_call+0x7e/0x1e0 [ +0.000000] do_idle+0x1e8/0x250 [ +0.000000] cpu_startup_entry+0x29/0x30 [ +0.000000] rest_init+0x151/0x160 [ +0.000000] start_kernel+0x6f3/0x700 [ +0.000000] x86_64_start_reservations+0x24/0x30 [ +0.000000] x86_64_start_kernel+0xc8/0xd0 [ +0.000000] common_startup_64+0x13e/0x148 [ +0.000000] irq event stamp: 6884 [ +0.000000] hardirqs last enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270 [ +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270 [ +0.000000] softirqs last enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270 [ +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140 [ +0.000000] other info that might help us debug this: [ +0.000000] Possible unsafe locking scenario: [ +0.000000] CPU0 [ +0.000000] ---- [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] <Interrupt> [ +0.000000] lock(&sch->root_lock_key); [ +0.000000] *** DEADLOCK *** [ +0.000000] 4 locks held by ping/156: [ +0.000000] #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40 [ +0.000000] #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190 [ +0.000000] #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950 [ +0.000000] #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140 I am able to reproduce it consistently when running the following: tc qdisc add dev lo handle 1: root dualpi2 ping -f 127.0.0.1 To fix it, make the timer run in softirq. Fixes: 320d031 ("sched: Struct definition and parsing of dualpi2 qdisc") Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

BPF CI testing report a UAF issue: [ 16.446633] BUG: kernel NULL pointer dereference, address: 000000000000003 0 [ 16.447134] #PF: supervisor read access in kernel mod e [ 16.447516] #PF: error_code(0x0000) - not-present pag e [ 16.447878] PGD 0 P4D 0 [ 16.448063] Oops: Oops: 0000 [#1] PREEMPT SMP NOPT I [ 16.448409] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Tainted: G OE 6.13.0-rc3-g89e8a75fda73-dirty #4 2 [ 16.449124] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODUL E [ 16.449502] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/201 4 [ 16.450201] Workqueue: smc_hs_wq smc_listen_wor k [ 16.450531] RIP: 0010:smc_listen_work+0xc02/0x159 0 [ 16.452158] RSP: 0018:ffffb5ab40053d98 EFLAGS: 0001024 6 [ 16.452526] RAX: 0000000000000001 RBX: 0000000000000002 RCX: 000000000000030 0 [ 16.452994] RDX: 0000000000000280 RSI: 00003513840053f0 RDI: 000000000000000 0 [ 16.453492] RBP: ffffa097808e3800 R08: ffffa09782dba1e0 R09: 000000000000000 5 [ 16.453987] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa0978274640 0 [ 16.454497] R13: 0000000000000000 R14: 0000000000000000 R15: ffffa09782d4092 0 [ 16.454996] FS: 0000000000000000(0000) GS:ffffa097bbc00000(0000) knlGS:000000000000000 0 [ 16.455557] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003 3 [ 16.455961] CR2: 0000000000000030 CR3: 0000000102788004 CR4: 0000000000770ef 0 [ 16.456459] PKRU: 5555555 4 [ 16.456654] Call Trace : [ 16.456832] <TASK > [ 16.456989] ? __die+0x23/0x7 0 [ 16.457215] ? page_fault_oops+0x180/0x4c 0 [ 16.457508] ? __lock_acquire+0x3e6/0x249 0 [ 16.457801] ? exc_page_fault+0x68/0x20 0 [ 16.458080] ? asm_exc_page_fault+0x26/0x3 0 [ 16.458389] ? smc_listen_work+0xc02/0x159 0 [ 16.458689] ? smc_listen_work+0xc02/0x159 0 [ 16.458987] ? lock_is_held_type+0x8f/0x10 0 [ 16.459284] process_one_work+0x1ea/0x6d 0 [ 16.459570] worker_thread+0x1c3/0x38 0 [ 16.459839] ? __pfx_worker_thread+0x10/0x1 0 [ 16.460144] kthread+0xe0/0x11 0 [ 16.460372] ? __pfx_kthread+0x10/0x1 0 [ 16.460640] ret_from_fork+0x31/0x5 0 [ 16.460896] ? __pfx_kthread+0x10/0x1 0 [ 16.461166] ret_from_fork_asm+0x1a/0x3 0 [ 16.461453] </TASK > [ 16.461616] Modules linked in: bpf_testmod(OE) [last unloaded: bpf_testmod(OE) ] [ 16.462134] CR2: 000000000000003 0 [ 16.462380] ---[ end trace 0000000000000000 ]--- [ 16.462710] RIP: 0010:smc_listen_work+0xc02/0x1590 The direct cause of this issue is that after smc_listen_out_connected(), newclcsock->sk may be NULL since it will releases the smcsk. Therefore, if the application closes the socket immediately after accept, newclcsock->sk can be NULL. A possible execution order could be as follows: smc_listen_work | userspace ----------------------------------------------------------------- lock_sock(sk) | smc_listen_out_connected() | | \- smc_listen_out | | | \- release_sock | | |- sk->sk_data_ready() | | fd = accept(); | close(fd); | \- socket->sk = NULL; /* newclcsock->sk is NULL now */ SMC_STAT_SERV_SUCC_INC(sock_net(newclcsock->sk)) Since smc_listen_out_connected() will not fail, simply swapping the order of the code can easily fix this issue. Fixes: 3b2dec2 ("net/smc: restructure client and server code in af_smc") Signed-off-by: D. Wythe <alibuda@linux.alibaba.com> Reviewed-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Reviewed-by: Dust Li <dust.li@linux.alibaba.com> Link: https://patch.msgid.link/20250818054618.41615-1-alibuda@linux.alibaba.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Receiving HSR frame with insufficient space to hold HSR tag in the skb can result in a crash (kernel BUG): [ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1 [ 45.392559] ------------[ cut here ]------------ [ 45.392912] kernel BUG at net/core/skbuff.c:211! [ 45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI [ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef) [ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0 <snip registers, remove unreliable trace> [ 45.402911] Call Trace: [ 45.403105] <IRQ> [ 45.404470] skb_push+0xcd/0xf0 [ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0 [ 45.406513] br_forward_finish+0x128/0x260 [ 45.408483] __br_forward+0x42d/0x590 [ 45.409464] maybe_deliver+0x2eb/0x420 [ 45.409763] br_flood+0x174/0x4a0 [ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0 [ 45.411618] br_handle_frame+0xac3/0x1230 [ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0 [ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0 [ 45.424478] __netif_receive_skb+0x22/0x170 [ 45.424806] process_backlog+0x242/0x6d0 [ 45.425116] __napi_poll+0xbb/0x630 [ 45.425394] net_rx_action+0x4d1/0xcc0 [ 45.427613] handle_softirqs+0x1a4/0x580 [ 45.427926] do_softirq+0x74/0x90 [ 45.428196] </IRQ> This issue was found by syzkaller. The panic happens in br_dev_queue_push_xmit() once it receives a corrupted skb with ETH header already pushed in linear data. When it attempts the skb_push() call, there's not enough headroom and skb_push() panics. The corrupted skb is put on the queue by HSR layer, which makes a sequence of unintended transformations when it receives a specific corrupted HSR frame (with incomplete TAG). Fix it by dropping and consuming frames that are not long enough to contain both ethernet and hsr headers. Alternative fix would be to check for enough headroom before skb_push() in br_dev_queue_push_xmit(). In the reproducer, this is injected via AF_PACKET, but I don't easily see why it couldn't be sent over the wire from adjacent network. Further Details: In the reproducer, the following network interface chain is set up: ┌────────────────┐ ┌────────────────┐ │ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐ └────────────────┘ └────────────────┘ │ │ ┌──────┐ ├─┤ hsr0 ├───┐ │ └──────┘ │ ┌────────────────┐ ┌────────────────┐ │ │┌────────┐ │ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │ └────────────────┘ └────────────────┘ ┌┼ bridge │ ││ │ │└────────┘ │ ┌───────┐ │ │ ... ├──────┘ └───────┘ To trigger the events leading up to crash, reproducer sends a corrupted HSR frame with incomplete TAG, via AF_PACKET socket on 'veth0_to_hsr'. The first HSR-layer function to process this frame is hsr_handle_frame(). It and then checks if the protocol is ETH_P_PRP or ETH_P_HSR. If it is, it calls skb_set_network_header(skb, ETH_HLEN + HSR_HLEN), without checking that the skb is long enough. For the crashing frame it is not, and hence the skb->network_header and skb->mac_len fields are set incorrectly, pointing after the end of the linear buffer. I will call this a BUG#1 and it is what is addressed by this patch. In the crashing scenario before the fix, the skb continues to go down the hsr path as follows. hsr_handle_frame() then calls this sequence hsr_forward_skb() fill_frame_info() hsr->proto_ops->fill_frame_info() hsr_fill_frame_info() hsr_fill_frame_info() contains a check that intends to check whether the skb actually contains the HSR header. But the check relies on the skb->mac_len field which was erroneously setup due to BUG#1, so the check passes and the execution continues back in the hsr_forward_skb(): hsr_forward_skb() hsr_forward_do() hsr->proto_ops->get_untagged_frame() hsr_get_untagged_frame() create_stripped_skb_hsr() In create_stripped_skb_hsr(), a copy of the skb is created and is further corrupted by operation that attempts to strip the HSR tag in a call to __pskb_copy(). The skb enters create_stripped_skb_hsr() with ethernet header pushed in linear buffer. The skb_pull(skb_in, HSR_HLEN) thus pulls 6 bytes of ethernet header into the headroom, creating skb_in with a headroom of size 8. The subsequent __pskb_copy() then creates an skb with headroom of just 2 and skb->len of just 12, this is how it looks after the copy: gdb) p skb->len $10 = 12 (gdb) p skb->data $11 = (unsigned char *) 0xffff888041e45382 "\252\252\252\252\252!\210\373", (gdb) p skb->head $12 = (unsigned char *) 0xffff888041e45380 "" It seems create_stripped_skb_hsr() assumes that ETH header is pulled in the headroom when it's entered, because it just pulls HSR header on top. But that is not the case in our code-path and we end up with the corrupted skb instead. I will call this BUG#2 *I got confused here because it seems that under no conditions can create_stripped_skb_hsr() work well, the assumption it makes is not true during the processing of hsr frames - since the skb_push() in hsr_handle_frame to skb_pull in hsr_deliver_master(). I wonder whether I missed something here.* Next, the execution arrives in hsr_deliver_master(). It calls skb_pull(ETH_HLEN), which just returns NULL - the SKB does not have enough space for the pull (as it only has 12 bytes in total at this point). *The skb_pull() here further suggests that ethernet header is meant to be pushed through the whole hsr processing and create_stripped_skb_hsr() should pull it before doing the HSR header pull.* hsr_deliver_master() then puts the corrupted skb on the queue, it is then picked up from there by bridge frame handling layer and finally lands in br_dev_queue_push_xmit where it panics. Cc: stable@kernel.org Fixes: 48b491a ("net: hsr: fix mac_len checks") Reported-by: syzbot+a81f2759d022496b40ab@syzkaller.appspotmail.com Signed-off-by: Jakub Acs <acsjakub@amazon.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250819082842.94378-1-acsjakub@amazon.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The mm/debug_vm_pagetable test allocates manually page table entries for the tests it runs, using also its manually allocated mm_struct. That in itself is ok, but when it exits, at destroy_args() it fails to clear those entries with the *_clear functions. The problem is that leaves stale entries. If another process allocates an mm_struct with a pgd at the same address, it may end up running into the stale entry. This is happening in practice on a debug kernel with CONFIG_DEBUG_VM_PGTABLE=y, for example this is the output with some extra debugging I added (it prints a warning trace if pgtables_bytes goes negative, in addition to the warning at check_mm() function): [ 2.539353] debug_vm_pgtable: [get_random_vaddr ]: random_vaddr is 0x7ea247140000 [ 2.539366] kmem_cache info [ 2.539374] kmem_cachep 0x000000002ce82385 - freelist 0x0000000000000000 - offset 0x508 [ 2.539447] debug_vm_pgtable: [init_args ]: args->mm is 0x000000002267cc9e (...) [ 2.552800] WARNING: CPU: 5 PID: 116 at include/linux/mm.h:2841 free_pud_range+0x8bc/0x8d0 [ 2.552816] Modules linked in: [ 2.552843] CPU: 5 UID: 0 PID: 116 Comm: modprobe Not tainted 6.12.0-105.debug_vm2.el10.ppc64le+debug #1 VOLUNTARY [ 2.552859] Hardware name: IBM,9009-41A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW910.00 (VL910_062) hv:phyp pSeries [ 2.552872] NIP: c0000000007eef3c LR: c0000000007eef30 CTR: c0000000003d8c90 [ 2.552885] REGS: c0000000622e73b0 TRAP: 0700 Not tainted (6.12.0-105.debug_vm2.el10.ppc64le+debug) [ 2.552899] MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002822 XER: 0000000a [ 2.552954] CFAR: c0000000008f03f0 IRQMASK: 0 [ 2.552954] GPR00: c0000000007eef30 c0000000622e7650 c000000002b1ac00 0000000000000001 [ 2.552954] GPR04: 0000000000000008 0000000000000000 c0000000007eef30 ffffffffffffffff [ 2.552954] GPR08: 00000000ffff00f5 0000000000000001 0000000000000048 0000000000004000 [ 2.552954] GPR12: 00000003fa440000 c000000017ffa300 c0000000051d9f80 ffffffffffffffdb [ 2.552954] GPR16: 0000000000000000 0000000000000008 000000000000000a 60000000000000e0 [ 2.552954] GPR20: 4080000000000000 c0000000113af038 00007fffcf130000 0000700000000000 [ 2.552954] GPR24: c000000062a6a000 0000000000000001 8000000062a68000 0000000000000001 [ 2.552954] GPR28: 000000000000000a c000000062ebc600 0000000000002000 c000000062ebc760 [ 2.553170] NIP [c0000000007eef3c] free_pud_range+0x8bc/0x8d0 [ 2.553185] LR [c0000000007eef30] free_pud_range+0x8b0/0x8d0 [ 2.553199] Call Trace: [ 2.553207] [c0000000622e7650] [c0000000007eef30] free_pud_range+0x8b0/0x8d0 (unreliable) [ 2.553229] [c0000000622e7750] [c0000000007f40b4] free_pgd_range+0x284/0x3b0 [ 2.553248] [c0000000622e7800] [c0000000007f4630] free_pgtables+0x450/0x570 [ 2.553274] [c0000000622e78e0] [c0000000008161c0] exit_mmap+0x250/0x650 [ 2.553292] [c0000000622e7a30] [c0000000001b95b8] __mmput+0x98/0x290 [ 2.558344] [c0000000622e7a80] [c0000000001d1018] exit_mm+0x118/0x1b0 [ 2.558361] [c0000000622e7ac0] [c0000000001d141c] do_exit+0x2ec/0x870 [ 2.558376] [c0000000622e7b60] [c0000000001d1ca8] do_group_exit+0x88/0x150 [ 2.558391] [c0000000622e7bb0] [c0000000001d1db8] sys_exit_group+0x48/0x50 [ 2.558407] [c0000000622e7be0] [c00000000003d810] system_call_exception+0x1e0/0x4c0 [ 2.558423] [c0000000622e7e50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec (...) [ 2.558892] ---[ end trace 0000000000000000 ]--- [ 2.559022] BUG: Bad rss-counter state mm:000000002267cc9e type:MM_ANONPAGES val:1 [ 2.559037] BUG: non-zero pgtables_bytes on freeing mm: -6144 Here the modprobe process ended up with an allocated mm_struct from the mm_struct slab that was used before by the debug_vm_pgtable test. That is not a problem, since the mm_struct is initialized again etc., however, if it ends up using the same pgd table, it bumps into the old stale entry when clearing/freeing the page table entries, so it tries to free an entry already gone (that one which was allocated by the debug_vm_pgtable test), which also explains the negative pgtables_bytes since it's accounting for not allocated entries in the current process. As far as I looked pgd_{alloc,free} etc. does not clear entries, and clearing of the entries is explicitly done in the free_pgtables-> free_pgd_range->free_p4d_range->free_pud_range->free_pmd_range-> free_pte_range path. However, the debug_vm_pgtable test does not call free_pgtables, since it allocates mm_struct and entries manually for its test and eg. not goes through page faults. So it also should clear manually the entries before exit at destroy_args(). This problem was noticed on a reboot X number of times test being done on a powerpc host, with a debug kernel with CONFIG_DEBUG_VM_PGTABLE enabled. Depends on the system, but on a 100 times reboot loop the problem could manifest once or twice, if a process ends up getting the right mm->pgd entry with the stale entries used by mm/debug_vm_pagetable. After using this patch, I couldn't reproduce/experience the problems anymore. I was able to reproduce the problem as well on latest upstream kernel (6.16). I also modified destroy_args() to use mmput() instead of mmdrop(), there is no reason to hold mm_users reference and not release the mm_struct entirely, and in the output above with my debugging prints I already had patched it to use mmput, it did not fix the problem, but helped in the debugging as well. Link: https://lkml.kernel.org/r/20250731214051.4115182-1-herton@redhat.com Fixes: 3c9b84f ("mm/debug_vm_pgtable: introduce struct pgtable_debug_args") Signed-off-by: Herton R. Krzesinski <herton@redhat.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Gavin Shan <gshan@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") introduced an IRQ lock inversion issue. Fix this lock inversion by changing the spin_lock_irq() calls into spin_lock_irqsave() calls in code that can be called either from interrupt context or from thread context. This patch fixes the following lockdep complaint: WARNING: possible irq lock inversion dependency detected 6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G W OE -------------------------------------------------------- kworker/u28:0/12 just changed the state of lock: ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110 but this lock took another, HARDIRQ-unsafe lock in the past: (shost->host_lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(shost->host_lock); local_irq_disable(); lock(&hba->clk_gating.lock); lock(shost->host_lock); <Interrupt> lock(&hba->clk_gating.lock); *** DEADLOCK *** 4 locks held by kworker/u28:0/12: #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104 the shortest dependencies between 2nd lock and 1st lock: -> (shost->host_lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 SOFTIRQ-ON-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock+0x48/0x64 ufshcd_sl_intr+0x4c/0xa08 ufshcd_threaded_intr+0x70/0x12c irq_thread_fn+0x48/0xa8 irq_thread+0x130/0x1ec kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10 ... acquired at: _raw_spin_lock_irqsave+0x5c/0x80 __ufshcd_release+0x78/0x118 ufshcd_send_uic_cmd+0xe4/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 -> (&hba->clk_gating.lock){-...}-{2:2} { IN-HARDIRQ-W at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 INITIAL USE at: lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_hold+0x34/0x14c ufshcd_send_uic_cmd+0x28/0x118 ufshcd_dme_set_attr+0x88/0x1c8 ufs_google_phy_initialization+0x68/0x418 [ufs] ufs_google_link_startup_notify+0x78/0x27c [ufs] ufshcd_link_startup+0x84/0x720 ufshcd_init+0xf3c/0x1330 ufshcd_pltfrm_init+0x728/0x7d8 ufs_google_probe+0x30/0x84 [ufs] platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa4/0x160 driver_probe_device+0x44/0x23c __driver_attach_async_helper+0x60/0xd4 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 } ... key at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10 ... acquired at: mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 stack backtrace: CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G W OE 6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: async async_run_entry_fn Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_irq_inversion_bug+0x2fc/0x304 mark_lock_irq+0x388/0x4fc mark_lock+0x1c4/0x224 __lock_acquire+0x438/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 ufshcd_release_scsi_cmd+0x60/0x110 ufshcd_compl_one_cqe+0x2c0/0x3f4 ufshcd_mcq_poll_cqe_lock+0xb0/0x104 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a] __handle_irq_event_percpu+0x104/0x32c handle_irq_event+0x40/0x9c handle_fasteoi_irq+0x170/0x2e8 generic_handle_domain_irq+0x58/0x80 gic_handle_irq+0x48/0x104 call_on_irq_stack+0x3c/0x50 do_interrupt_handler+0x7c/0xd8 el1_interrupt+0x34/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c _raw_spin_unlock_irqrestore+0x3c/0x6c debug_object_assert_init+0x16c/0x21c __mod_timer+0x4c/0x48c schedule_timeout+0xd4/0x16c io_schedule_timeout+0x48/0x70 do_wait_for_common+0x100/0x194 wait_for_completion_io_timeout+0x48/0x6c blk_execute_rq+0x124/0x17c scsi_execute_cmd+0x18c/0x3f8 scsi_probe_and_add_lun+0x204/0xd74 __scsi_add_device+0xbc/0x120 ufshcd_async_scan+0x80/0x3c0 async_run_entry_fn+0x4c/0x17c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: Neil Armstrong <neil.armstrong@linaro.org> Cc: André Draszik <andre.draszik@linaro.org> Reviewed-by: Peter Wang <peter.wang@mediatek.com> Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20250815155842.472867-2-bvanassche@acm.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

These iterations require the read lock, otherwise RCU lockdep will splat: ============================= WARNING: suspicious RCU usage 6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G O ----------------------------- drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 5 locks held by rtcwake/547: #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98 stack backtrace: CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G O 6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY Tainted: [O]=OOT_MODULE Stack: 223721b3a80 6089eac6 00000001 00000001 ffffff00 6089eac6 00000535 6086e528 721b3ac0 6003c294 00000000 60031fc0 Call Trace: [<600407ed>] show_stack+0x10e/0x127 [<6003c294>] dump_stack_lvl+0x77/0xc6 [<6003c2fd>] dump_stack+0x1a/0x20 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e [<603d980f>] device_suspend+0x528/0x541 [<603da24b>] dpm_suspend+0x1a2/0x267 [<603da837>] dpm_suspend_start+0x5d/0x72 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736 [...] Add the fourth argument to the iteration to annotate this and avoid the splat. Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents") Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

syzbot reported the splat below. [0] When atmtcp_v_open() or atmtcp_v_close() is called via connect() or close(), atmtcp_send_control() is called to send an in-kernel special message. The message has ATMTCP_HDR_MAGIC in atmtcp_control.hdr.length. Also, a pointer of struct atm_vcc is set to atmtcp_control.vcc. The notable thing is struct atmtcp_control is uAPI but has a space for an in-kernel pointer. struct atmtcp_control { struct atmtcp_hdr hdr; /* must be first */ ... atm_kptr_t vcc; /* both directions */ ... } __ATM_API_ALIGN; typedef struct { unsigned char _[8]; } __ATM_API_ALIGN atm_kptr_t; The special message is processed in atmtcp_recv_control() called from atmtcp_c_send(). atmtcp_c_send() is vcc->dev->ops->send() and called from 2 paths: 1. .ndo_start_xmit() (vcc->send() == atm_send_aal0()) 2. vcc_sendmsg() The problem is sendmsg() does not validate the message length and userspace can abuse atmtcp_recv_control() to overwrite any kptr by atmtcp_control. Let's add a new ->pre_send() hook to validate messages from sendmsg(). [0]: Oops: general protection fault, probably for non-canonical address 0xdffffc00200000ab: 0000 [#1] SMP KASAN PTI KASAN: probably user-memory-access in range [0x0000000100000558-0x000000010000055f] CPU: 0 UID: 0 PID: 5865 Comm: syz-executor331 Not tainted 6.17.0-rc1-syzkaller-00215-gbab3ce404553 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:atmtcp_recv_control drivers/atm/atmtcp.c:93 [inline] RIP: 0010:atmtcp_c_send+0x1da/0x950 drivers/atm/atmtcp.c:297 Code: 4d 8d 75 1a 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 15 06 00 00 41 0f b7 1e 4d 8d b7 60 05 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 13 06 00 00 66 41 89 1e 4d 8d 75 1c 4c RSP: 0018:ffffc90003f5f810 EFLAGS: 00010203 RAX: 00000000200000ab RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802a510000 RSI: 00000000ffffffff RDI: ffff888030a6068c RBP: ffff88802699fb40 R08: ffff888030a606eb R09: 1ffff1100614c0dd R10: dffffc0000000000 R11: ffffffff8718fc40 R12: dffffc0000000000 R13: ffff888030a60680 R14: 000000010000055f R15: 00000000ffffffff FS: 00007f8d7e9236c0(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045ad50 CR3: 0000000075bde000 CR4: 00000000003526f0 Call Trace: <TASK> vcc_sendmsg+0xa10/0xc60 net/atm/common.c:645 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8d7e96a4a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8d7e923198 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8d7e9f4308 RCX: 00007f8d7e96a4a9 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000005 RBP: 00007f8d7e9f4300 R08: 65732f636f72702f R09: 65732f636f72702f R10: 65732f636f72702f R11: 0000000000000246 R12: 00007f8d7e9c10ac R13: 00007f8d7e9231a0 R14: 0000200000000200 R15: 0000200000000250 </TASK> Modules linked in: Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+1741b56d54536f4ec349@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/68a6767c.050a0220.3d78fd.0011.GAE@google.com/ Tested-by: syzbot+1741b56d54536f4ec349@syzkaller.appspotmail.com Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250821021901.2814721-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

If preparing a write bio fails then blk_zone_wplug_bio_work() calls bio_endio() with zwplug->lock held. If a device mapper driver is stacked on top of the zoned block device then this results in nested locking of zwplug->lock. The resulting lockdep complaint is a false positive because this is nested locking and not recursive locking. Suppress this false positive by calling blk_zone_wplug_bio_io_error() without holding zwplug->lock. This is safe because no code in blk_zone_wplug_bio_io_error() depends on zwplug->lock being held. This patch suppresses the following lockdep complaint: WARNING: possible recursive locking detected -------------------------------------------- kworker/3:0H/46 is trying to acquire lock: ffffff882968b830 (&zwplug->lock){-...}-{2:2}, at: blk_zone_write_plug_bio_endio+0x64/0x1f0 but task is already holding lock: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&zwplug->lock); lock(&zwplug->lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kworker/3:0H/46: #0: ffffff8809486758 ((wq_completion)sdd_zwplugs){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c #1: ffffffc085de3d70 ((work_completion)(&zwplug->bio_work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c #2: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c stack backtrace: CPU: 3 UID: 0 PID: 46 Comm: kworker/3:0H Tainted: G W OE 6.12.38-android16-5-maybe-dirty-4k #1 8b362b6f76e3645a58cd27d86982bce10d150025 Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: Spacecraft board based on MALIBU (DT) Workqueue: sdd_zwplugs blk_zone_wplug_bio_work Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 print_deadlock_bug+0x38c/0x398 __lock_acquire+0x13e8/0x2e1c lock_acquire+0x134/0x2b4 _raw_spin_lock_irqsave+0x5c/0x80 blk_zone_write_plug_bio_endio+0x64/0x1f0 bio_endio+0x9c/0x240 __dm_io_complete+0x214/0x260 clone_endio+0xe8/0x214 bio_endio+0x218/0x240 blk_zone_wplug_bio_work+0x204/0x48c process_one_work+0x26c/0x65c worker_thread+0x33c/0x498 kthread+0x110/0x134 ret_from_fork+0x10/0x20 Cc: stable@vger.kernel.org Cc: Damien Le Moal <dlemoal@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Fixes: dd291d7 ("block: Introduce zone write plugging") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20250825182720.1697203-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>

into HEAD KVM/riscv fixes for 6.17, take #1 - Fix pte settings within kvm_riscv_gstage_ioremap() - Fix comments in kvm_riscv_check_vcpu_requests() - Fix stack overrun when setting vlenb via ONE_REG

commit c652887 ("KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap") makes the allocation of vPEs depend on nASSGIcap for GICv4.1 hosts. While the vGIC v4 initialization and teardown is handled correctly, it erroneously attempts to establish a vLPI mapping to a VM that has no vPEs allocated: Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a8 Mem abort info: ESR = 0x0000000096000044 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000 CM = 0, WnR = 1, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000073a453b000 [00000000000000a8] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000044 [#1] SMP pstate: 23400009 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : its_irq_set_vcpu_affinity+0x58c/0x95c lr : its_irq_set_vcpu_affinity+0x1e0/0x95c sp : ffff8001029bb9e0 pmr_save: 00000060 x29: ffff8001029bba20 x28: ffff0001ca5e28c0 x27: 0000000000000000 x26: 0000000000000000 x25: ffff00019eee9f80 x24: ffff0001992b3f00 x23: ffff8001029bbab8 x22: ffff00001159fb80 x21: 00000000000024a7 x20: 00000000000024a7 x19: ffff00019eee9fb4 x18: 0000000000000494 x17: 000000000000000e x16: 0000000000000494 x15: 0000000000000002 x14: ffff0001a7f34600 x13: ffffccaad1203000 x12: 0000000000000018 x11: ffff000011991000 x10: 0000000000000000 x9 : 00000000000000a2 x8 : 00000000000020a8 x7 : 0000000000000000 x6 : 000000000000003f x5 : 0000000000000040 x4 : 0000000000000000 x3 : 0000000000000004 x2 : 0000000000000000 x1 : ffff8001029bbab8 x0 : 00000000000000a8 Call trace: its_irq_set_vcpu_affinity+0x58c/0x95c irq_set_vcpu_affinity+0x74/0xc8 its_map_vlpi+0x4c/0x94 kvm_vgic_v4_set_forwarding+0x134/0x298 kvm_arch_irq_bypass_add_producer+0x28/0x34 irq_bypass_register_producer+0xf8/0x1d8 vfio_msi_set_vector_signal+0x2c8/0x308 vfio_pci_set_msi_trigger+0x198/0x2d4 vfio_pci_set_irqs_ioctl+0xf0/0x104 vfio_pci_core_ioctl+0x6ac/0xc5c vfio_device_fops_unl_ioctl+0x128/0x370 __arm64_sys_ioctl+0x98/0xd0 el0_svc_common+0xd8/0x1d8 do_el0_svc+0x28/0x34 el0_svc+0x40/0xb8 el0t_64_sync_handler+0x70/0xbc el0t_64_sync+0x1a8/0x1ac Code: 321f0129 f940094a 8b08014 d1400900 (39000009) ---[ end trace 0000000000000000 ]--- Fix it by moving the GICv4.1 special-casing to vgic_supports_direct_msis(), returning false if the user explicitly disabled nASSGIcap for the VM. Fixes: c652887 ("KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap") Suggested-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Link: https://lore.kernel.org/r/20250729210644.830364-1-rananta@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

In gicv5_irs_of_init_affinity() a WARN_ON() is triggered if: 1) a phandle in the "cpus" property does not correspond to a valid OF node 2 a CPU logical id does not exist for a given OF cpu_node #1 is a firmware bug and should be reported as such but does not warrant a WARN_ON() backtrace. #2 is not necessarily an error condition (eg a kernel can be booted with nr_cpus=X limiting the number of cores artificially) and therefore there is no reason to clutter the kernel log with WARN_ON() output when the condition is hit. Rework the IRS affinity parsing code to remove undue WARN_ON()s thus making it less noisy. Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250814094138.1611017-1-lpieralisi@kernel.org

micromaomao added 6 commits November 23, 2024 18:21

Very basic instant checkpoint implementation with read/write syscall PoC

fdc8c87

Allow revert without re-checkpointing

5e948fc

Clean up, document issue

765b948

Remove confusing note

b176966

Merge branch 'dev' into ick

1f3f81a

make oldconfig

9f4d4a2

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