Fix some potential memory leaks in error handling branches while
iterating dent entries. For example, function dbg_check_dir()
forgets to free pdent if it exists.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 1e51764 ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

A detach hung is possible when a race occurs between the detach process
and the ubi background thread. The following sequences outline the race:

  ubi thread: if (list_empty(&ubi->works)...

  ubi detach: set_bit(KTHREAD_SHOULD_STOP, &kthread->flags)
              => by kthread_stop()
              wake_up_process()
              => ubi thread is still running, so 0 is returned

  ubi thread: set_current_state(TASK_INTERRUPTIBLE)
              schedule()
              => ubi thread will never be scheduled again

  ubi detach: wait_for_completion()
              => hung task!

To fix that, we need to check kthread_should_stop() after we set the
task state, so the ubi thread will either see the stop bit and exit or
the task state is reset to runnable such that it isn't scheduled out
indefinitely.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 801c135 ("UBI: Unsorted Block Images")
Reported-by: syzbot+853639d0cb16c31c7a14@syzkaller.appspotmail.com
Signed-off-by: Richard Weinberger <richard@nod.at>

…inode

Changing xattr of a temp file will trigger following assertion failed
and make ubifs turn into readonly filesystem:
  ubifs_assert_failed [ubifs]: UBIFS assert failed: host->i_nlink > 0,
  in fs/ubifs/journal.c:1801

Reproducer:
  1. fd = open(__O_TMPFILE)
  2. fsetxattr(fd, key, value2, XATTR_CREATE)
  3. fsetxattr(fd, key, value2, XATTR_REPLACE)

Fix this by removing assertion 'nlink > 0' for host inode.

Reported-by: Chengsong Ke <kechengsong@huawei.com>
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

…re() fails

Following process will trigger ubifs_err:
  1. useradd -m freg                                        (Under root)
  2. cd /home/freg && mkdir mp                              (Under freg)
  3. mount -t ubifs /dev/ubi0_0 /home/freg/mp               (Under root)
  4. cd /home/freg && echo 123 > mp/a			    (Under root)
  5. cd mp && chown freg a && chgrp freg a && chmod 777 a   (Under root)
  6. chattr +i a                                            (Under freg)

UBIFS error (ubi0:0 pid 1723): ubifs_ioctl [ubifs]: can't modify inode
65 attributes
chattr: Operation not permitted while setting flags on a

This is not an UBIFS problem, it was caused by task priviliage checking
on file operations. Remove error message printing from kernel just like
other filesystems (eg. ext4), since we already have enough information
from userspace tools.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Fixes the following W=1 kernel build warning(s):

fs/ubifs/auth.c:66: warning: Excess function parameter 'hash' description in 'ubifs_prepare_auth_node'

Rename hash to inhash.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Fixes the following W=1 kernel build warning(s):

fs/ubifs/gc.c:70: warning: Excess function parameter 'buf' description in 'switch_gc_head'
fs/ubifs/gc.c:70: warning: Excess function parameter 'len' description in 'switch_gc_head'
fs/ubifs/gc.c:70: warning: Excess function parameter 'lnum' description in 'switch_gc_head'
fs/ubifs/gc.c:70: warning: Excess function parameter 'offs' description in 'switch_gc_head'

They're not in use. Remove them.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Fixes the following W=1 kernel build warning(s):

fs/ubifs/replay.c:942: warning: Excess function parameter 'ref_lnum' description in 'validate_ref'
fs/ubifs/replay.c:942: warning: Excess function parameter 'ref_offs' description in 'validate_ref'

They're not in use. Remove them.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Fixes the following W=1 kernel build warning(s):

fs/ubifs/tnc.c:3479: warning: Excess function parameter 'inum' description in 'dbg_check_inode_size'
fs/ubifs/tnc.c:366: warning: Excess function parameter 'node' description in 'lnc_free'

@Inum in 'dbg_check_inode_size' should be @iNode, fix it.
@node in 'lnc_free' is not in use, Remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

When removing the last reference of an inode the size of an auth node
is already part of write_len. So we must not call ubifs_add_auth_dirt().
Call it only when needed.

Cc: <stable@vger.kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Kristof Havasi <havasiefr@gmail.com>
Fixes: 6a98bc4 ("ubifs: Add authentication nodes to journal")
Reported-and-tested-by: Kristof Havasi <havasiefr@gmail.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

Fix a memory leak after dumping authentication mount options in error
handling branch.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>  # 4.20+
Fixes: d8a2277 ("ubifs: Enable authentication support")
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

There is no need to dump authentication options while remounting,
because authentication initialization can only be doing once in
the first mount process. Dumping authentication mount options in
remount process may cause memory leak if UBIFS has already been
mounted with old authentication mount options.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>  # 4.20+
Fixes: d8a2277 ("ubifs: Enable authentication support")
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

… path

Release the authentication related resource in some error handling
branches in mount_ubifs().

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>  # 4.20+
Fixes: d8a2277 ("ubifs: Enable authentication support")
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

The bpf_prog is being checked for !NULL after uml_kmalloc
but later its used directly for example:
bpf_prog->filter = bpf and is also later returned upon
success. Fix this, do a NULL check and return right away.

Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Use GFP_ATOMIC instead of GFP_KERNEL under spin lock to fix possible
sleep-in-atomic-context bugs.

Fixes: 9807019 ("um: Loadable BPF "Firmware" for vector drivers")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

musl toolchain and headers are a bit more strict. These fixes enable building
UML with musl as well as seem not to break on glibc.

Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

It is possible to produce a statically linked UML binary with UML_NET_VECTOR,
UML_NET_VDE and UML_NET_PCAP options enabled using alternative libc
implementations, which do not rely on NSS, such as musl.

Allow static linking in this case.

Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

As the comment here indicates, we need to do the polling in the
idle loop without blocking interrupts, since interrupts can be
vhost-user messages that we must process even while in our idle
loop.

I don't know why I explained one thing and implemented another,
but we have indeed observed random hangs due to this, depending
on the timing of the messages.

Fixes: 88ce642 ("um: Implement time-travel=ext")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

For external time travel, the protocol says to return the
incoming sequence number in the ACK message to aid debugging,
so do that.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Lockdep complains at boot:

=============================
[ BUG: Invalid wait context ]
5.7.0-05093-g46d91ecd597b #98 Not tainted
-----------------------------
swapper/1 is trying to lock:
0000000060931b98 (&desc[i].request_mutex){+.+.}-{3:3}, at: __setup_irq+0x11d/0x623
other info that might help us debug this:
context-{4:4}
1 lock held by swapper/1:
 #0: 000000006074fed8 (sigio_spinlock){+.+.}-{2:2}, at: sigio_lock+0x1a/0x1c
stack backtrace:
CPU: 0 PID: 1 Comm: swapper Not tainted 5.7.0-05093-g46d91ecd597b #98
Stack:
 7fa4fab0 6028dfd1 0000002a 6008bea5
 7fa50700 7fa50040 7fa4fac0 6028e016
 7fa4fb50 6007f6da 60959c18 00000000
Call Trace:
 [<60023a0e>] show_stack+0x13b/0x155
 [<6028e016>] dump_stack+0x2a/0x2c
 [<6007f6da>] __lock_acquire+0x515/0x15f2
 [<6007eb50>] lock_acquire+0x245/0x273
 [<6050d9f1>] __mutex_lock+0xbd/0x325
 [<6050dc76>] mutex_lock_nested+0x1d/0x1f
 [<6008e27e>] __setup_irq+0x11d/0x623
 [<6008e8ed>] request_threaded_irq+0x169/0x1a6
 [<60021eb0>] um_request_irq+0x1ee/0x24b
 [<600234ee>] write_sigio_irq+0x3b/0x76
 [<600383ca>] sigio_broken+0x146/0x2e4
 [<60020bd8>] do_one_initcall+0xde/0x281

Because we hold sigio_spinlock and then get into requesting
an interrupt with a mutex.

Change the spinlock to a mutex to avoid that.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Fix below warnings reported by coccicheck:
./arch/um/drivers/vector_user.c:403:2-7: WARNING: NULL check before some freeing functions is not needed.

Fixes: bc8f8e4 ("um: Add a generic "fd" vector transport")
Signed-off-by: Li Heng <liheng40@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

This seems like a dead artifact since TIF_IA32 is not even defined as a
TI flag for UM.  Looking back in git history, it made sense in the old
days, but it is apparently not used since UM was split out of the x86
arch/.  It is also going away from the x86 tree soon.

Also, I think the variable clean up it performs is not needed as 64-bit
UML doesn't run 32-bit binaries as far as I can tell, and 32-bit UML
has 32-bit ulong.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

pids are no longer limited to 16-bits, bump to 32-bits,
ie. 9 decimal characters.  Additionally sizeof("/") already
returns 2 - ie. it already accounts for trailing zero.

Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Linux UM Mailing List <linux-um@lists.infradead.org>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

We currently get a few stray newlines, due to the interaction
between printk() and the code here. Remove a few explicit
newline prints to neaten the output.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Provide functionality roughly compatible with the existing qemu
ifup scripting:
* invocation of an ifup script. The interface name is passed as the
  first and only argument
* allocating tap interfaces on the fly if they are not explicitly
  specified

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

…kernel/git/rw/ubifs

Pull ubifs updates from Richard Weinberger:

 - Kernel-doc fixes

 - Fixes for memory leaks in authentication option parsing

* tag 'for-linus-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubifs: mount_ubifs: Release authentication resource in error handling path
  ubifs: Don't parse authentication mount options in remount process
  ubifs: Fix a memleak after dumping authentication mount options
  ubifs: Fix some kernel-doc warnings in tnc.c
  ubifs: Fix some kernel-doc warnings in replay.c
  ubifs: Fix some kernel-doc warnings in gc.c
  ubifs: Fix 'hash' kernel-doc warning in auth.c

…linux/kernel/git/rw/ubifs

Pull more ubi and ubifs updates from Richard Weinberger:
 "UBI:
   - Correctly use kthread_should_stop in ubi worker

  UBIFS:
   - Fixes for memory leaks while iterating directory entries
   - Fix for a user triggerable error message
   - Fix for a space accounting bug in authenticated mode"

* tag 'for-linus-5.10-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubifs: journal: Make sure to not dirty twice for auth nodes
  ubifs: setflags: Don't show error message when vfs_ioc_setflags_prepare() fails
  ubifs: ubifs_jnl_change_xattr: Remove assertion 'nlink > 0' for host inode
  ubi: check kthread_should_stop() after the setting of task state
  ubifs: dent: Fix some potential memory leaks while iterating entries
  ubifs: xattr: Fix some potential memory leaks while iterating entries

…kernel/git/rw/uml

Pull UML updates from Richard Weinberger:

 - Improve support for non-glibc systems

 - Vector: Add support for scripting and dynamic tap devices

 - Various fixes for the vector networking driver

 - Various fixes for time travel mode

* tag 'for-linus-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: vector: Add dynamic tap interfaces and scripting
  um: Clean up stacktrace dump
  um: Fix incorrect assumptions about max pid length
  um: Remove dead usage of TIF_IA32
  um: Remove redundant NULL check
  um: change sigio_spinlock to a mutex
  um: time-travel: Return the sequence number in ACK messages
  um: time-travel: Fix IRQ handling in time_travel_handle_message()
  um: Allow static linking for non-glibc implementations
  um: Some fixes to build UML with musl
  um: vector: Use GFP_ATOMIC under spin lock
  um: Fix null pointer dereference in vector_user_bpf