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2024-01-01Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
2023-01-06Update copyright dates with scripts/update-copyrightsJoseph Myers1-1/+1
2022-01-01Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2021-09-03Remove "Contributed by" linesSiddhesh Poyarekar1-1/+0
We stopped adding "Contributed by" or similar lines in sources in 2012 in favour of git logs and keeping the Contributors section of the glibc manual up to date. Removing these lines makes the license header a bit more consistent across files and also removes the possibility of error in attribution when license blocks or files are copied across since the contributed-by lines don't actually reflect reality in those cases. Move all "Contributed by" and similar lines (Written by, Test by, etc.) into a new file CONTRIBUTED-BY to retain record of these contributions. These contributors are also mentioned in manual/contrib.texi, so we just maintain this additional record as a courtesy to the earlier developers. The following scripts were used to filter a list of files to edit in place and to clean up the CONTRIBUTED-BY file respectively. These were not added to the glibc sources because they're not expected to be of any use in future given that this is a one time task: https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22Remove malloc hooks [BZ #23328]Siddhesh Poyarekar1-1/+5
Make malloc hooks symbols compat-only so that new applications cannot link against them and remove the declarations from the API. Also remove the unused malloc-hooks.h. Finally, mark all symbols in libc_malloc_debug.so as compat so that the library cannot be linked against. Add a note about the deprecation in NEWS. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22Move malloc_{g,s}et_state to libc_malloc_debugSiddhesh Poyarekar1-114/+0
These deprecated functions are only safe to call from __malloc_initialize_hook and as a result, are not useful in the general case. Move the implementations to libc_malloc_debug so that existing binaries that need it will now have to preload the debug DSO to work correctly. This also allows simplification of the core malloc implementation by dropping all the undumping support code that was added to make malloc_set_state work. One known breakage is that of ancient emacs binaries that depend on this. They will now crash when running with this libc. With LD_BIND_NOW=1, it will terminate immediately because of not being able to find malloc_set_state but with lazy binding it will crash in unpredictable ways. It will need a preloaded libc_malloc_debug.so so that its initialization hook is executed to allow its malloc implementation to work properly. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22glibc.malloc.check: Wean away from malloc hooksSiddhesh Poyarekar1-9/+0
The malloc-check debugging feature is tightly integrated into glibc malloc, so thanks to an idea from Florian Weimer, much of the malloc implementation has been moved into libc_malloc_debug.so to support malloc-check. Due to this, glibc malloc and malloc-check can no longer work together; they use altogether different (but identical) structures for heap management. This should not make a difference though since the malloc check hook is not disabled anywhere. malloc_set_state does, but it does so early enough that it shouldn't cause any problems. The malloc check tunable is now in the debug DSO and has no effect when the DSO is not preloaded. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22mcheck: Wean away from malloc hooks [BZ #23489]Siddhesh Poyarekar1-58/+3
Split the mcheck implementation into the debugging hooks and API so that the API can be replicated in libc and libc_malloc_debug.so. The libc APIs always result in failure. The mcheck implementation has also been moved entirely into libc_malloc_debug.so and with it, all of the hook initialization code can now be moved into the debug library. Now the initialization can be done independently of libc internals. With this patch, libc_malloc_debug.so can no longer be used with older libcs, which is not its goal anyway. tst-vfork3 breaks due to this since it spawns shell scripts, which in turn execute using the system glibc. Move the test to tests-container so that only the built glibc is used. This move also fixes bugs in the mcheck version of memalign and realloc, thus allowing removal of the tests from tests-mcheck exclusion list. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22Move malloc hooks into a compat DSOSiddhesh Poyarekar1-11/+53
Remove all malloc hook uses from core malloc functions and move it into a new library libc_malloc_debug.so. With this, the hooks now no longer have any effect on the core library. libc_malloc_debug.so is a malloc interposer that needs to be preloaded to get hooks functionality back so that the debugging features that depend on the hooks, i.e. malloc-check, mcheck and mtrace work again. Without the preloaded DSO these debugging features will be nops. These features will be ported away from hooks in subsequent patches. Similarly, legacy applications that need hooks functionality need to preload libc_malloc_debug.so. The symbols exported by libc_malloc_debug.so are maintained at exactly the same version as libc.so. Finally, static binaries will no longer be able to use malloc debugging features since they cannot preload the debugging DSO. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22Remove __morecore and __default_morecoreSiddhesh Poyarekar1-0/+2
Make the __morecore and __default_morecore symbols compat-only and remove their declarations from the API. Also, include morecore.c directly into malloc.c; this should ideally get merged into malloc in a future cleanup. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22Remove __after_morecore_hookSiddhesh Poyarekar1-0/+5
Remove __after_morecore_hook from the API and finalize the symbol so that it can no longer be used in new applications. Old applications using __after_morecore_hook will find that their hook is no longer called. Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-04hooks.c: Remove incorrect commentSiddhesh Poyarekar1-4/+0
The comment about different values of glibc.malloc.check is no longer valid.
2021-07-03Move glibc.malloc.check implementation into its own fileSiddhesh Poyarekar1-370/+1
Separate the malloc check implementation from the malloc hooks. They still use the hooks but are now maintained in a separate file. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-05-17Missing ENOMEM in realloc_check wrapper (bug 27870)Andreas Schwab1-1/+4
When MALLOC_CHECK_ is non-zero, the realloc hook missed to set errno to ENOMEM when called with too big size. Run the test tst-malloc-too-large also with MALLOC_CHECK_=3 to catch that.
2021-03-26malloc: Rename chunk2rawmemSzabolcs Nagy1-2/+2
The previous patch ensured that all chunk to mem computations use chunk2rawmem, so now we can rename it to chunk2mem, and in the few cases where the tag of mem is relevant chunk2mem_tag can be used. Replaced tag_at (chunk2rawmem (x)) with chunk2mem_tag (x). Renamed chunk2rawmem to chunk2mem. Reviewed-by: DJ Delorie <dj@redhat.com>
2021-03-26malloc: Use chunk2rawmem throughoutSzabolcs Nagy1-1/+1
The difference between chunk2mem and chunk2rawmem is that the latter does not get the memory tag for the returned pointer. It turns out chunk2rawmem almost always works: The input of chunk2mem is a chunk pointer that is untagged so it can access the chunk header. All memory that is not user allocated heap memory is untagged, which in the current implementation means that it has the 0 tag, but this patch does not rely on the tag value. The patch relies on that chunk operations are either done on untagged chunks or without doing memory access to the user owned part. Internal interface contracts: sysmalloc: Returns untagged memory. _int_malloc: Returns untagged memory. _int_free: Takes untagged memory. _int_memalign: Returns untagged memory. _int_realloc: Takes and returns tagged memory. So only _int_realloc and functions outside this list need care. Alignment checks do not need the right tag and tcache works with untagged memory. tag_at was kept in realloc after an mremap, which is not strictly necessary, since the pointer is only used to retag the memory, but this way the tag is guaranteed to be different from the old tag. Reviewed-by: DJ Delorie <dj@redhat.com>
2021-03-26malloc: Use memsize instead of CHUNK_AVAILABLE_SIZESzabolcs Nagy1-6/+5
This is a pure refactoring change that does not affect behaviour. The CHUNK_AVAILABLE_SIZE name was unclear, the memsize name tries to follow the existing convention of mem denoting the allocation that is handed out to the user, while chunk is its internally used container. The user owned memory for a given chunk starts at chunk2mem(p) and the size is memsize(p). It is not valid to use on dumped heap chunks. Moved the definition next to other chunk and mem related macros. Reviewed-by: DJ Delorie <dj@redhat.com>
2021-03-26malloc: Use mtag_enabled instead of USE_MTAGSzabolcs Nagy1-6/+4
Use the runtime check where possible: it should not cause slow down in the !USE_MTAG case since then mtag_enabled is constant false, but it allows compiling the tagging logic so it's less likely to break or diverge when developers only test the !USE_MTAG case. Reviewed-by: DJ Delorie <dj@redhat.com>
2021-03-26malloc: Refactor TAG_ macros to avoid indirectionSzabolcs Nagy1-5/+5
This does not change behaviour, just removes one layer of indirection in the internal memory tagging logic. Use tag_ and mtag_ prefixes instead of __tag_ and __mtag_ since these are all symbols with internal linkage, private to malloc.c, so there is no user namespace pollution issue. Reviewed-by: DJ Delorie <dj@redhat.com>
2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2020-12-30malloc: preserve errno on mcheck hooks [BZ #17924]Adhemerval Zanella1-5/+11
Similar to the fix 69fda43b8d, save and restore errno for the hook functions used for MALLOC_CHECK_=3. It fixes the malloc/tst-free-errno-mcheck regression. Checked on x86_64-linux-gnu.
2020-12-24MTE: Do not pad size in realloc_checkSiddhesh Poyarekar1-4/+5
The MTE patch to add malloc support incorrectly padded the size passed to _int_realloc by SIZE_SZ when it ought to have sent just the chunksize. Revert that bit of the change so that realloc works correctly with MALLOC_CHECK_ set. This also brings the realloc_check implementation back in sync with libc_realloc.
2020-12-21malloc: Basic support for memory tagging in the malloc() familyRichard Earnshaw1-27/+52
This patch adds the basic support for memory tagging. Various flavours are supported, particularly being able to turn on tagged memory at run-time: this allows the same code to be used on systems where memory tagging support is not present without neededing a separate build of glibc. Also, depending on whether the kernel supports it, the code will use mmap for the default arena if morecore does not, or cannot support tagged memory (on AArch64 it is not available). All the hooks use function pointers to allow this to work without needing ifuncs. Reviewed-by: DJ Delorie <dj@redhat.com>
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert1-1/+1
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-04-18malloc: make malloc fail with requests larger than PTRDIFF_MAX (BZ#23741)Adhemerval Zanella1-7/+10
As discussed previously on libc-alpha [1], this patch follows up the idea and add both the __attribute_alloc_size__ on malloc functions (malloc, calloc, realloc, reallocarray, valloc, pvalloc, and memalign) and limit maximum requested allocation size to up PTRDIFF_MAX (taking into consideration internal padding and alignment). This aligns glibc with gcc expected size defined by default warning -Walloc-size-larger-than value which warns for allocation larger than PTRDIFF_MAX. It also aligns with gcc expectation regarding libc and expected size, such as described in PR#67999 [2] and previously discussed ISO C11 issues [3] on libc-alpha. From the RFC thread [4] and previous discussion, it seems that consensus is only to limit such requested size for malloc functions, not the system allocation one (mmap, sbrk, etc.). The implementation changes checked_request2size to check for both overflow and maximum object size up to PTRDIFF_MAX. No additional checks are done on sysmalloc, so it can still issue mmap with values larger than PTRDIFF_T depending on the requested size. The __attribute_alloc_size__ is for functions that return a pointer only, which means it cannot be applied to posix_memalign (see remarks in GCC PR#87683 [5]). The runtimes checks to limit maximum requested allocation size does applies to posix_memalign. Checked on x86_64-linux-gnu and i686-linux-gnu. [1] https://sourceware.org/ml/libc-alpha/2018-11/msg00223.html [2] https://gcc.gnu.org/bugzilla//show_bug.cgi?id=67999 [3] https://sourceware.org/ml/libc-alpha/2011-12/msg00066.html [4] https://sourceware.org/ml/libc-alpha/2018-11/msg00224.html [5] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87683 [BZ #23741] * malloc/hooks.c (malloc_check, realloc_check): Use __builtin_add_overflow on overflow check and adapt to checked_request2size change. * malloc/malloc.c (__libc_malloc, __libc_realloc, _mid_memalign, __libc_pvalloc, __libc_calloc, _int_memalign): Limit maximum allocation size to PTRDIFF_MAX. (REQUEST_OUT_OF_RANGE): Remove macro. (checked_request2size): Change to inline function and limit maximum requested size to PTRDIFF_MAX. (__libc_malloc, __libc_realloc, _int_malloc, _int_memalign): Limit maximum allocation size to PTRDIFF_MAX. (_mid_memalign): Use _int_memalign call for overflow check. (__libc_pvalloc): Use __builtin_add_overflow on overflow check. (__libc_calloc): Use __builtin_mul_overflow for overflow check and limit maximum requested size to PTRDIFF_MAX. * malloc/malloc.h (malloc, calloc, realloc, reallocarray, memalign, valloc, pvalloc): Add __attribute_alloc_size__. * stdlib/stdlib.h (malloc, realloc, reallocarray, valloc): Likewise. * malloc/tst-malloc-too-large.c (do_test): Add check for allocation larger than PTRDIFF_MAX. * malloc/tst-memalign.c (do_test): Disable -Walloc-size-larger-than= around tests of malloc with negative sizes. * malloc/tst-posix_memalign.c (do_test): Likewise. * malloc/tst-pvalloc.c (do_test): Likewise. * malloc/tst-valloc.c (do_test): Likewise. * malloc/tst-reallocarray.c (do_test): Replace call to reallocarray with resulting size allocation larger than PTRDIFF_MAX with reallocarray_nowarn. (reallocarray_nowarn): New function. * NEWS: Mention the malloc function semantic change.
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-06-29malloc: Update heap dumping/undumping comments [BZ #23351]Florian Weimer1-36/+6
Also remove a few now-unused declarations and definitions. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2018-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2017-10-15Silence -O3 -Wall warning in malloc/hooks.c with GCC 7 [BZ #22052]H.J. Lu1-0/+7
realloc_check has unsigned char *magic_p; ... __libc_lock_lock (main_arena.mutex); const mchunkptr oldp = mem2chunk_check (oldmem, &magic_p); __libc_lock_unlock (main_arena.mutex); if (!oldp) malloc_printerr ("realloc(): invalid pointer"); ... if (newmem == NULL) *magic_p ^= 0xFF; with static void malloc_printerr(const char *str) __attribute__ ((noreturn)); GCC 7 -O3 warns hooks.c: In function ‘realloc_check’: hooks.c:352:14: error: ‘magic_p’ may be used uninitialized in this function [-Werror=maybe-uninitialized] *magic_p ^= 0xFF; due to the GCC bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82090 This patch silences GCC 7 by using DIAG_IGNORE_NEEDS_COMMENT. [BZ #22052] * malloc/hooks.c (realloc_check): Use DIAG_IGNORE_NEEDS_COMMENT to silence -O3 -Wall warning with GCC 7.
2017-08-31malloc: Remove the internal_function attributeFlorian Weimer1-2/+0
2017-08-31malloc: Change top_check return type to voidFlorian Weimer1-14/+12
After commit ec2c1fcefb200c6cb7e09553f3c6af8815013d83, (malloc: Abort on heap corruption, without a backtrace), the function always returns 0.
2017-08-30malloc: Remove check_action variable [BZ #21754]Florian Weimer1-50/+5
Clean up calls to malloc_printerr and trim its argument list. This also removes a few bits of work done before calling malloc_printerr (such as unlocking operations). The tunable/environment variable still enables the lightweight additional malloc checking, but mallopt (M_CHECK_ACTION) no longer has any effect.
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2016-10-28malloc: Use accessors for chunk metadata accessFlorian Weimer1-4/+4
This change allows us to change the encoding of these struct members in a centralized fashion.
2016-10-26malloc: Remove malloc_get_state, malloc_set_state [BZ #19473]Florian Weimer1-49/+14
After the removal of __malloc_initialize_hook, newly compiled Emacs binaries are no longer able to use these interfaces. malloc_get_state is only used during the Emacs build process, so we provide a stub implementation only. Existing Emacs binaries will not call this stub function, but still reference the symbol. The rewritten tst-mallocstate test constructs a dumped heap which should approximates what existing Emacs binaries pass to glibc malloc.
2016-09-06malloc: Automated part of conversion to __libc_lockFlorian Weimer1-14/+14
2016-05-24malloc: Correct malloc alignment on 32-bit architectures [BZ #6527]Florian Weimer1-1/+1
After the heap rewriting added in commit 4cf6c72fd2a482e7499c29162349810029632c3f (malloc: Rewrite dumped heap for compatibility in __malloc_set_state), we can change malloc alignment for new allocations because the alignment of old allocations no longer matters. We need to increase the malloc state version number, so that binaries containing dumped heaps of the new layout will not try to run on previous versions of glibc, resulting in obscure crashes. This commit addresses a failure of tst-malloc-thread-fail on the affected architectures (32-bit ppc and mips) because the test checks pointer alignment.
2016-05-13malloc: Rewrite dumped heap for compatibility in __malloc_set_stateFlorian Weimer1-100/+50
This will allow us to change many aspects of the malloc implementation while preserving compatibility with existing Emacs binaries. As a result, existing Emacs binaries will have a larger RSS, and Emacs needs a few more milliseconds to start. This overhead is specific to Emacs (and will go away once Emacs switches to its internal malloc). The new checks to make free and realloc compatible with the dumped heap are confined to the mmap paths, which are already quite slow due to the munmap overhead. This commit weakens some security checks, but only for heap pointers in the dumped main arena. By default, this area is empty, so those checks are as effective as before.
2016-02-19malloc: Remove max_total_mem member form struct malloc_parFlorian Weimer1-1/+1
Also note that sumblks in struct mallinfo is always 0. No functional change.
2016-01-04Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2015-05-19Fix for test "malloc_usable_size: expected 7 but got 11"James Lemke1-24/+38
[BZ #17581] The checking chain of unused chunks was terminated by a hash of the block pointer, which was sometimes confused with the chunk length byte. We now avoid using a length byte equal to the magic byte.
2015-05-19Avoid deadlock in malloc on backtrace (BZ #16159)Siddhesh Poyarekar1-4/+8
When the malloc subsystem detects some kind of memory corruption, depending on the configuration it prints the error, a backtrace, a memory map and then aborts the process. In this process, the backtrace() call may result in a call to malloc, resulting in various kinds of problematic behavior. In one case, the malloc it calls may detect a corruption and call backtrace again, and a stack overflow may result due to the infinite recursion. In another case, the malloc it calls may deadlock on an arena lock with the malloc (or free, realloc, etc.) that detected the corruption. In yet another case, if the program is linked with pthreads, backtrace may do a pthread_once initialization, which deadlocks on itself. In all these cases, the program exit is not as intended. This is avoidable by marking the arena that malloc detected a corruption on, as unusable. The following patch does that. Features of this patch are as follows: - A flag is added to the mstate struct of the arena to indicate if the arena is corrupt. - The flag is checked whenever malloc functions try to get a lock on an arena. If the arena is unusable, a NULL is returned, causing the malloc to use mmap or try the next arena. - malloc_printerr sets the corrupt flag on the arena when it detects a corruption - free does not concern itself with the flag at all. It is not important since the backtrace workflow does not need free. A free in a parallel thread may cause another corruption, but that's not new - The flag check and set are not atomic and may race. This is fine since we don't care about contention during the flag check. We want to make sure that the malloc call in the backtrace does not trip on itself and all that action happens in the same thread and not across threads. I verified that the test case does not show any regressions due to this patch. I also ran the malloc benchmarks and found an insignificant difference in timings (< 2%). * malloc/Makefile (tests): New test case tst-malloc-backtrace. * malloc/arena.c (arena_lock): Check if arena is corrupt. (reused_arena): Find a non-corrupt arena. (heap_trim): Pass arena to unlink. * malloc/hooks.c (malloc_check_get_size): Pass arena to malloc_printerr. (top_check): Likewise. (free_check): Likewise. (realloc_check): Likewise. * malloc/malloc.c (malloc_printerr): Add arena argument. (unlink): Likewise. (munmap_chunk): Adjust. (ARENA_CORRUPTION_BIT): New macro. (arena_is_corrupt): Likewise. (set_arena_corrupt): Likewise. (sysmalloc): Use mmap if there are no usable arenas. (_int_malloc): Likewise. (__libc_malloc): Don't fail if arena_get returns NULL. (_mid_memalign): Likewise. (__libc_calloc): Likewise. (__libc_realloc): Adjust for additional argument to malloc_printerr. (_int_free): Likewise. (malloc_consolidate): Likewise. (_int_realloc): Likewise. (_int_memalign): Don't touch corrupt arenas. * malloc/tst-malloc-backtrace.c: New test case.
2015-01-02Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2014-12-11Fix for test "malloc_usable_size: expected 7 but got 11"James Lemke1-44/+35
[BZ #17581] Revert this fix while investigating a problem.
2014-12-01Fix for test "malloc_usable_size: expected 7 but got 11"James Lemke1-35/+44
[BZ #17581] The checking chain of unused chunks was terminated by a hash of the block pointer, which was sometimes confused with the chunk length byte. The chain is now terminated by a NULL byte.
2014-01-02Reformat malloc to gnu style.Ondřej Bílka1-294/+354
2014-01-01Update copyright notices with scripts/update-copyrightsAllan McRae1-1/+1
2013-12-10Expand MALLOC_COPY and MALLOC_ZERO to memcpy and memset.Ondřej Bílka1-1/+1
2013-12-10Drop PER_THREAD conditionals from malloc.Ondřej Bílka1-4/+0