406506ca92
In short the easy handle needs to be disconnected from its connection at this point since the connection still is serving other easy handles. In our app we can reliably reproduce a crash in our http2 stress test that is fixed by this change. I can't easily reproduce the same test in a small example. This is the gdb/asan output: ==11785==ERROR: AddressSanitizer: heap-use-after-free on address 0xe9f4fb80 at pc 0x09f41f19 bp 0xf27be688 sp 0xf27be67c READ of size 4 at 0xe9f4fb80 thread T13 (RESOURCE_HTTP) #0 0x9f41f18 in curl_multi_remove_handle /path/to/source/3rdparty/curl/lib/multi.c:666 0xe9f4fb80 is located 0 bytes inside of 1128-byte region [0xe9f4fb80,0xe9f4ffe8) freed by thread T13 (RESOURCE_HTTP) here: #0 0xf7b1b5c2 in __interceptor_free /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_malloc_linux.cc:45 #1 0x9f7862d in conn_free /path/to/source/3rdparty/curl/lib/url.c:2808 #2 0x9f78c6a in Curl_disconnect /path/to/source/3rdparty/curl/lib/url.c:2876 #3 0x9f41b09 in multi_done /path/to/source/3rdparty/curl/lib/multi.c:615 #4 0x9f48017 in multi_runsingle /path/to/source/3rdparty/curl/lib/multi.c:1896 #5 0x9f490f1 in curl_multi_perform /path/to/source/3rdparty/curl/lib/multi.c:2123 #6 0x9c4443c in perform /path/to/source/src/net/resourcemanager/ResourceManagerCurlThread.cpp:854 #7 0x9c445e0 in ... #8 0x9c4cf1d in ... #9 0xa2be6b5 in ... #10 0xf7aa5780 in asan_thread_start /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_interceptors.cc:226 #11 0xf4d3a16d in __clone (/lib/i386-linux-gnu/libc.so.6+0xe716d) previously allocated by thread T13 (RESOURCE_HTTP) here: #0 0xf7b1ba27 in __interceptor_calloc /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_malloc_linux.cc:70 #1 0x9f7dfa6 in allocate_conn /path/to/source/3rdparty/curl/lib/url.c:3904 #2 0x9f88ca0 in create_conn /path/to/source/3rdparty/curl/lib/url.c:5797 #3 0x9f8c928 in Curl_connect /path/to/source/3rdparty/curl/lib/url.c:6438 #4 0x9f45a8c in multi_runsingle /path/to/source/3rdparty/curl/lib/multi.c:1411 #5 0x9f490f1 in curl_multi_perform /path/to/source/3rdparty/curl/lib/multi.c:2123 #6 0x9c4443c in perform /path/to/source/src/net/resourcemanager/ResourceManagerCurlThread.cpp:854 #7 0x9c445e0 in ... #8 0x9c4cf1d in ... #9 0xa2be6b5 in ... #10 0xf7aa5780 in asan_thread_start /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_interceptors.cc:226 #11 0xf4d3a16d in __clone (/lib/i386-linux-gnu/libc.so.6+0xe716d) SUMMARY: AddressSanitizer: heap-use-after-free /path/to/source/3rdparty/curl/lib/multi.c:666 in curl_multi_remove_handle Shadow bytes around the buggy address: 0x3d3e9f20: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9f30: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9f40: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9f50: fd fd fd fd fd fd fd fd fd fd fd fd fd fa fa fa 0x3d3e9f60: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa =>0x3d3e9f70:[fd]fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9f80: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9f90: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9fa0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9fb0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x3d3e9fc0: 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 Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 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 ==11785==ABORTING Thread 14 "RESOURCE_HTTP" received signal SIGABRT, Aborted. [Switching to Thread 0xf27bfb40 (LWP 12324)] 0xf7fd8be9 in __kernel_vsyscall () (gdb) bt #0 0xf7fd8be9 in __kernel_vsyscall () #1 0xf4c7ee89 in __GI_raise (sig=6) at ../sysdeps/unix/sysv/linux/raise.c:54 #2 0xf4c803e7 in __GI_abort () at abort.c:89 #3 0xf7b2ef2e in __sanitizer::Abort () at /opt/toolchain/src/gcc-6.2.0/libsanitizer/sanitizer_common/sanitizer_posix_libcdep.cc:122 #4 0xf7b262fa in __sanitizer::Die () at /opt/toolchain/src/gcc-6.2.0/libsanitizer/sanitizer_common/sanitizer_common.cc:145 #5 0xf7b21ab3 in __asan::ScopedInErrorReport::~ScopedInErrorReport (this=0xf27be171, __in_chrg=<optimized out>) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_report.cc:689 #6 0xf7b214a5 in __asan::ReportGenericError (pc=166993689, bp=4068206216, sp=4068206204, addr=3925146496, is_write=false, access_size=4, exp=0, fatal=true) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_report.cc:1074 #7 0xf7b21fce in __asan::__asan_report_load4 (addr=3925146496) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_rtl.cc:129 #8 0x09f41f19 in curl_multi_remove_handle (multi=0xf3406080, data=0xde582400) at /path/to/source3rdparty/curl/lib/multi.c:666 #9 0x09f6b277 in Curl_close (data=0xde582400) at /path/to/source3rdparty/curl/lib/url.c:415 #10 0x09f3354e in curl_easy_cleanup (data=0xde582400) at /path/to/source3rdparty/curl/lib/easy.c:860 #11 0x09c6de3f in ... #12 0x09c378c5 in ... #13 0x09c48133 in ... #14 0x09c4d092 in ... #15 0x0a2be6b6 in ... #16 0xf7aa5781 in asan_thread_start (arg=0xf2d22938) at /opt/toolchain/src/gcc-6.2.0/libsanitizer/asan/asan_interceptors.cc:226 #17 0xf5de52b5 in start_thread (arg=0xf27bfb40) at pthread_create.c:333 #18 0xf4d3a16e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:114 Fixes #1083 |
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.github | ||
CMake | ||
docs | ||
include | ||
lib | ||
m4 | ||
packages | ||
projects | ||
scripts | ||
src | ||
tests | ||
winbuild | ||
.dir-locals.el | ||
.gitattributes | ||
.gitignore | ||
.travis.yml | ||
acinclude.m4 | ||
appveyor.yml | ||
buildconf | ||
buildconf.bat | ||
CHANGES | ||
CHANGES.0 | ||
CMakeLists.txt | ||
configure.ac | ||
COPYING | ||
CTestConfig.cmake | ||
curl-config.in | ||
GIT-INFO | ||
libcurl.pc.in | ||
MacOSX-Framework | ||
Makefile.am | ||
Makefile.dist | ||
maketgz | ||
README | ||
README.md | ||
RELEASE-NOTES |
Curl is a command-line tool for transferring data specified with URL syntax. Find out how to use curl by reading the curl.1 man page or the MANUAL document. Find out how to install Curl by reading the INSTALL document.
libcurl is the library curl is using to do its job. It is readily available to be used by your software. Read the libcurl.3 man page to learn how!
You find answers to the most frequent questions we get in the FAQ document.
Study the COPYING file for distribution terms and similar. If you distribute curl binaries or other binaries that involve libcurl, you might enjoy the LICENSE-MIXING document.
Contact
If you have problems, questions, ideas or suggestions, please contact us by posting to a suitable mailing list.
All contributors to the project are listed in the THANKS document.
Website
Visit the curl web site for the latest news and downloads.
Git
To download the very latest source off the Git server do this:
git clone https://github.com/curl/curl.git
(you'll get a directory named curl created, filled with the source code)
Notice
Curl contains pieces of source code that is Copyright (c) 1998, 1999 Kungliga Tekniska Högskolan. This notice is included here to comply with the distribution terms.