Net::MailMessage: Double free if Content-Disposition header is empty #4687
Description
Describe the bug
During the fuzzing test for Poco::Net::MailMessage ASAN reports a heap-use-after-free (which is actually double-free) issue. This happens if a parsed message is a multipart message with an empty Content-Disposition header.
To Reproduce
Poco::MemoryInputStream stream(input.data(), input.size());
Poco::Net::MailMessage mail;
mail.read(stream);with the following input: crash-a50113a66f7c8d5530f3446b7c74a5cbc04668a2.txt
Expected behavior
The message is parsed without an error.
Logs
=================================================================
==575941==ERROR: AddressSanitizer: heap-use-after-free on address 0x515000615380 at pc 0x7fd7e5e2e9f9 bp 0x7ffc405f5e50 sp 0x7ffc405f5e48
READ of size 8 at 0x515000615380 thread T0
#0 0x7fd7e5e2e9f8 in Poco::Net::MailMessage::~MailMessage() poco/Net/src/MailMessage.cpp:219:3
#1 0x561b1a8ed8e3 in LLVMFuzzerTestOneInput poco/fuzzing/http_messages_fuzzer.cc:47:3
#2 0x561b1a7f9920 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4c920)
#3 0x561b1a7f9095 in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool, bool*) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4c095)
#4 0x561b1a7fa875 in fuzzer::Fuzzer::MutateAndTestOne() (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4d875)
#5 0x561b1a7fb485 in fuzzer::Fuzzer::Loop(std::vector<fuzzer::SizedFile, std::allocator<fuzzer::SizedFile>>&) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4e485)
#6 0x561b1a7e95eb in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x3c5eb)
#7 0x561b1a812622 in main (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x65622)
#8 0x7fd7e4b82d8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
#9 0x7fd7e4b82e3f in __libc_start_main csu/../csu/libc-start.c:392:3
#10 0x561b1a7dea54 in _start (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x31a54)
0x515000615380 is located 0 bytes inside of 504-byte region [0x515000615380,0x515000615578)
freed by thread T0 here:
#0 0x561b1a8ebbbd in operator delete(void*) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x13ebbd)
#1 0x7fd7e5fe99b3 in Poco::Net::StringPartSource::~StringPartSource() poco/Net/src/StringPartSource.cpp:45:1
#2 0x7fd7e5e2ea3b in Poco::Net::MailMessage::~MailMessage() poco/Net/src/MailMessage.cpp:219:3
#3 0x561b1a8ed8e3 in LLVMFuzzerTestOneInput poco/fuzzing/http_messages_fuzzer.cc:47:3
#4 0x561b1a7f9920 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4c920)
#5 0x561b1a7f9095 in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool, bool*) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4c095)
#6 0x561b1a7fa875 in fuzzer::Fuzzer::MutateAndTestOne() (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4d875)
#7 0x561b1a7fb485 in fuzzer::Fuzzer::Loop(std::vector<fuzzer::SizedFile, std::allocator<fuzzer::SizedFile>>&) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4e485)
#8 0x561b1a7e95eb in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x3c5eb)
#9 0x561b1a812622 in main (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x65622)
#10 0x7fd7e4b82d8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
previously allocated by thread T0 here:
#0 0x561b1a8eb35d in operator new(unsigned long) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x13e35d)
#1 0x7fd7e5e39176 in Poco::Net::MailMessage::createPartStore(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>> const&) poco/Net/src/MailMessage.cpp:694:30
#2 0x7fd7e5e3c197 in Poco::Net::(anonymous namespace)::MultiPartHandler::handlePart(Poco::Net::MessageHeader const&, std::istream&) poco/Net/src/MailMessage.cpp:102:30
#3 0x7fd7e5e3731d in Poco::Net::MailMessage::handlePart(std::istream&, Poco::Net::MessageHeader const&, Poco::Net::PartHandler&) poco/Net/src/MailMessage.cpp:537:10
#4 0x7fd7e5e332a8 in Poco::Net::MailMessage::readPart(std::istream&, Poco::Net::MessageHeader const&, Poco::Net::PartHandler&) poco/Net/src/MailMessage.cpp:514:9
#5 0x7fd7e5e32916 in Poco::Net::MailMessage::readMultipart(std::istream&, Poco::Net::PartHandler&) poco/Net/src/MailMessage.cpp:495:3
#6 0x7fd7e5e33be2 in Poco::Net::MailMessage::read(std::istream&) poco/Net/src/MailMessage.cpp:363:3
#7 0x561b1a8ed8b5 in LLVMFuzzerTestOneInput poco/fuzzing/http_messages_fuzzer.cc:46:10
#8 0x561b1a7f9920 in fuzzer::Fuzzer::ExecuteCallback(unsigned char const*, unsigned long) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4c920)
#9 0x561b1a7f9095 in fuzzer::Fuzzer::RunOne(unsigned char const*, unsigned long, bool, fuzzer::InputInfo*, bool, bool*) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4c095)
#10 0x561b1a7fa875 in fuzzer::Fuzzer::MutateAndTestOne() (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4d875)
#11 0x561b1a7fb485 in fuzzer::Fuzzer::Loop(std::vector<fuzzer::SizedFile, std::allocator<fuzzer::SizedFile>>&) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x4e485)
#12 0x561b1a7e95eb in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char const*, unsigned long)) (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x3c5eb)
#13 0x561b1a812622 in main (poco/fuzzing/prefix/bin/http_messages_fuzzer+0x65622)
#14 0x7fd7e4b82d8f in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
SUMMARY: AddressSanitizer: heap-use-after-free poco/Net/src/MailMessage.cpp:219:3 in Poco::Net::MailMessage::~MailMessage()
Shadow bytes around the buggy address:
0x515000615100: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x515000615180: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x515000615200: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x515000615280: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x515000615300: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x515000615380:[fd]fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x515000615400: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x515000615480: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x515000615500: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fa
0x515000615580: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
0x515000615600: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
Intra object redzone: bb
ASan internal: fe
Left alloca redzone: ca
Right alloca redzone: cb
==575941==ABORTING
MS: 1 CrossOver-; base unit: 1cb911899a10687a9b6b2eb3ef9db81abcc6c10c
artifact_prefix='./'; Test unit written to ./crash-a50113a66f7c8d5530f3446b7c74a5cbc04668a2