Florian Weimer [Fri, 22 Nov 2019 21:10:42 +0000 (22:10 +0100)]
libio: Disable vtable validation for pre-2.1 interposed handles [BZ #25203]
Commit c402355dfa7807b8e0adb27c009135a7e2b9f1b0 ("libio: Disable
vtable validation in case of interposition [BZ #23313]") only covered
the interposable glibc 2.1 handles, in libio/stdfiles.c. The
parallel code in libio/oldstdfiles.c needs similar detection logic.
rtld: Check __libc_enable_secure before honoring LD_PREFER_MAP_32BIT_EXEC (CVE-2019-19126) [BZ #25204]
The problem was introduced in glibc 2.23, in commit b9eb92ab05204df772eb4929eccd018637c9f3e9
("Add Prefer_MAP_32BIT_EXEC to map executable pages with MAP_32BIT").
mips: Force RWX stack for hard-float builds that can run on pre-4.8 kernels
Linux/Mips kernels prior to 4.8 could potentially crash the user
process when doing FPU emulation while running on non-executable
user stack.
Currently, gcc doesn't emit .note.GNU-stack for mips, but that will
change in the future. To ensure that glibc can be used with such
future gcc, without silently resulting in binaries that might crash
in runtime, this patch forces RWX stack for all built objects if
configured to run against minimum kernel version less than 4.8.
* sysdeps/unix/sysv/linux/mips/Makefile
(test-xfail-check-execstack):
Move under mips-has-gnustack != yes.
(CFLAGS-.o*, ASFLAGS-.o*): New rules.
Apply -Wa,-execstack if mips-force-execstack == yes.
* sysdeps/unix/sysv/linux/mips/configure: Regenerated.
* sysdeps/unix/sysv/linux/mips/configure.ac
(mips-force-execstack): New var.
Set to yes for hard-float builds with minimum_kernel < 4.8.0
or minimum_kernel not set at all.
(mips-has-gnustack): New var.
Use value of libc_cv_as_noexecstack
if mips-force-execstack != yes, otherwise set to no.
Andreas Schwab [Tue, 14 May 2019 15:14:59 +0000 (17:14 +0200)]
Fix crash in _IO_wfile_sync (bug 20568)
When computing the length of the converted part of the stdio buffer, use
the number of consumed wide characters, not the (negative) distance to the
end of the wide buffer.
Stefan Liebler [Thu, 7 Feb 2019 14:18:36 +0000 (15:18 +0100)]
Add compiler barriers around modifications of the robust mutex list for pthread_mutex_trylock. [BZ #24180]
While debugging a kernel warning, Thomas Gleixner, Sebastian Sewior and
Heiko Carstens found a bug in pthread_mutex_trylock due to misordered
instructions:
140: a5 1b 00 01 oill %r1,1
144: e5 48 a0 f0 00 00 mvghi 240(%r10),0 <--- THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
14a: e3 10 a0 e0 00 24 stg %r1,224(%r10) <--- last THREAD_SETMEM of ENQUEUE_MUTEX_PI
Please have a look at the discussion:
"Re: WARN_ON_ONCE(!new_owner) within wake_futex_pi() triggerede"
(https://lore.kernel.org/lkml/20190202112006.GB3381@osiris/)
This patch is introducing the same compiler barriers and comments
for pthread_mutex_trylock as introduced for pthread_mutex_lock and
pthread_mutex_timedlock by commit 8f9450a0b7a9e78267e8ae1ab1000ebca08e473e
"Add compiler barriers around modifications of the robust mutex list."
ChangeLog:
[BZ #24180]
* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock):
Add compiler barriers and comments.
H.J. Lu [Mon, 4 Feb 2019 16:55:52 +0000 (08:55 -0800)]
x86-64 memcmp: Use unsigned Jcc instructions on size [BZ #24155]
Since the size argument is unsigned. we should use unsigned Jcc
instructions, instead of signed, to check size.
Tested on x86-64 and x32, with and without --disable-multi-arch.
[BZ #24155]
CVE-2019-7309
* NEWS: Updated for CVE-2019-7309.
* sysdeps/x86_64/memcmp.S: Use RDX_LP for size. Clear the
upper 32 bits of RDX register for x32. Use unsigned Jcc
instructions, instead of signed.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-memcmp-2.
* sysdeps/x86_64/x32/tst-size_t-memcmp-2.c: New test.
H.J. Lu [Fri, 1 Feb 2019 20:24:08 +0000 (12:24 -0800)]
x86-64 strnlen/wcsnlen: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes strnlen/wcsnlen for x32. Tested on x86-64 and x32. On
x86-64, libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/strlen.S: Use RSI_LP for length.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-strnlen.
* sysdeps/x86_64/x32/tst-size_t-strnlen.c: New file.
H.J. Lu [Fri, 1 Feb 2019 20:23:23 +0000 (12:23 -0800)]
x86-64 strncpy: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes strncpy for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/multiarch/strcpy-sse2-unaligned.S: Use RDX_LP
for length.
* sysdeps/x86_64/multiarch/strcpy-ssse3.S: Likewise.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-strncpy.
* sysdeps/x86_64/x32/tst-size_t-strncpy.c: New file.
H.J. Lu [Fri, 1 Feb 2019 20:22:33 +0000 (12:22 -0800)]
x86-64 strncmp family: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes the strncmp family for x32. Tested on x86-64 and x32.
On x86-64, libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/multiarch/strcmp-sse42.S: Use RDX_LP for length.
* sysdeps/x86_64/strcmp.S: Likewise.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-strncasecmp,
tst-size_t-strncmp and tst-size_t-wcsncmp.
* sysdeps/x86_64/x32/tst-size_t-strncasecmp.c: New file.
* sysdeps/x86_64/x32/tst-size_t-strncmp.c: Likewise.
* sysdeps/x86_64/x32/tst-size_t-wcsncmp.c: Likewise.
H.J. Lu [Fri, 1 Feb 2019 20:21:41 +0000 (12:21 -0800)]
x86-64 memset/wmemset: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes memset/wmemset for x32. Tested on x86-64 and x32. On
x86-64, libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/multiarch/memset-avx512-no-vzeroupper.S: Use
RDX_LP for length. Clear the upper 32 bits of RDX register.
* sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S: Likewise.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-memset.
* sysdeps/x86_64/x32/tst-size_t-memset.c: New file.
H.J. Lu [Fri, 1 Feb 2019 20:20:54 +0000 (12:20 -0800)]
x86-64 memrchr: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes memrchr for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/memrchr.S: Use RDX_LP for length.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-memrchr.
* sysdeps/x86_64/x32/tst-size_t-memrchr.c: New file.
H.J. Lu [Fri, 1 Feb 2019 20:20:06 +0000 (12:20 -0800)]
x86-64 memcpy: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes memcpy for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/multiarch/memcpy-ssse3-back.S: Use RDX_LP for
length. Clear the upper 32 bits of RDX register.
* sysdeps/x86_64/multiarch/memcpy-ssse3.S: Likewise.
* sysdeps/x86_64/multiarch/memmove-avx512-no-vzeroupper.S:
Likewise.
* sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S:
Likewise.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-memcpy.
tst-size_t-wmemchr.
* sysdeps/x86_64/x32/tst-size_t-memcpy.c: New file.
H.J. Lu [Fri, 1 Feb 2019 20:19:07 +0000 (12:19 -0800)]
x86-64 memcmp/wmemcmp: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes memcmp/wmemcmp for x32. Tested on x86-64 and x32. On
x86-64, libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/multiarch/memcmp-sse4.S: Use RDX_LP for length.
Clear the upper 32 bits of RDX register.
* sysdeps/x86_64/multiarch/memcmp-ssse3.S: Likewise.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-memcmp and
tst-size_t-wmemcmp.
* sysdeps/x86_64/x32/tst-size_t-memcmp.c: New file.
* sysdeps/x86_64/x32/tst-size_t-wmemcmp.c: Likewise.
H.J. Lu [Fri, 1 Feb 2019 20:17:09 +0000 (12:17 -0800)]
x86-64 memchr/wmemchr: Properly handle the length parameter [BZ #24097]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes memchr/wmemchr for x32. Tested on x86-64 and x32. On
x86-64, libc.so is the same with and withou the fix.
[BZ #24097]
CVE-2019-6488
* sysdeps/x86_64/memchr.S: Use RDX_LP for length. Clear the
upper 32 bits of RDX register.
* sysdeps/x86_64/x32/Makefile (tests): Add tst-size_t-memchr.
* sysdeps/x86_64/x32/test-size_t.h: New file.
* sysdeps/x86_64/x32/tst-size_t-memchr.c: Likewise.
Florian Weimer [Mon, 31 Dec 2018 21:04:36 +0000 (22:04 +0100)]
malloc: Always call memcpy in _int_realloc [BZ #24027]
This commit removes the custom memcpy implementation from _int_realloc
for small chunk sizes. The ncopies variable has the wrong type, and
an integer wraparound could cause the existing code to copy too few
elements (leaving the new memory region mostly uninitialized).
Therefore, removing this code fixes bug 24027.
Stefan Liebler [Thu, 6 Sep 2018 12:27:03 +0000 (14:27 +0200)]
Fix segfault in maybe_script_execute.
If glibc is built with gcc 8 and -march=z900,
the testcase posix/tst-spawn4-compat crashes with a segfault.
In function maybe_script_execute, the new_argv array is dynamically
initialized on stack with (argc + 1) elements.
The function wants to add _PATH_BSHELL as the first argument
and writes out of bounds of new_argv.
There is an off-by-one because maybe_script_execute fails to count
the terminating NULL when sizing new_argv.
ChangeLog:
* sysdeps/unix/sysv/linux/spawni.c (maybe_script_execute):
Increment size of new_argv by one.
powerpc: Fix syscalls during early process initialization [BZ #22685]
The tunables framework needs to execute syscall early in process
initialization, before the TCB is available for consumption. This
behavior conflicts with powerpc{|64|64le}'s lock elision code, that
checks the TCB before trying to abort transactions immediately before
executing a syscall.
This patch adds a powerpc-specific implementation of __access_noerrno
that does not abort transactions before the executing syscall.
Tested on powerpc{|64|64le}.
[BZ #22685]
* sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION_IMPL): Renamed
from ABORT_TRANSACTION.
(ABORT_TRANSACTION): Redirect to ABORT_TRANSACTION_IMPL.
* sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION,
ABORT_TRANSACTION_IMPL): Likewise.
* sysdeps/unix/sysv/linux/powerpc/not-errno.h: New file. Reuse
Linux code, but remove the code that aborts transactions.
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com> Tested-by: Aurelien Jarno <aurelien@aurel32.net>
(cherry picked from commit 4612268a0ad8e3409d8ce2314dd2dd8ee0af5269)
tunables: Use direct syscall for access (BZ#21744)
The function maybe_enable_malloc_check, which is called by
__tunables_init, calls __access_noerrno. It isn't problem when
symbol is is in ld.so, which has a special version of __access_noerrno
without stack protector. But when glibc is built with stack protector,
maybe_enable_malloc_check in libc.a can't call the regular version of
__access_noerrno with stack protector.
This patch changes how Linux defines the __access_noerrno to be an
inline call instead and thus preventing defining different build
rules for ld/static and shared.
H.J. Lu <hongjiu.lu@intel.com>
Adhemerval Zanella <adhemerval.zanella@linaro.org>
Arjun Shankar [Thu, 18 Jan 2018 16:47:06 +0000 (16:47 +0000)]
Fix integer overflows in internal memalign and malloc [BZ #22343] [BZ #22774]
When posix_memalign is called with an alignment less than MALLOC_ALIGNMENT
and a requested size close to SIZE_MAX, it falls back to malloc code
(because the alignment of a block returned by malloc is sufficient to
satisfy the call). In this case, an integer overflow in _int_malloc leads
to posix_memalign incorrectly returning successfully.
Upon fixing this and writing a somewhat thorough regression test, it was
discovered that when posix_memalign is called with an alignment larger than
MALLOC_ALIGNMENT (so it uses _int_memalign instead) and a requested size
close to SIZE_MAX, a different integer overflow in _int_memalign leads to
posix_memalign incorrectly returning successfully.
Both integer overflows affect other memory allocation functions that use
_int_malloc (one affected malloc in x86) or _int_memalign as well.
This commit fixes both integer overflows. In addition to this, it adds a
regression test to guard against false successful allocations by the
following memory allocation functions when called with too-large allocation
sizes and, where relevant, various valid alignments:
malloc, realloc, calloc, memalign, posix_memalign, aligned_alloc, valloc,
and pvalloc.
H.J. Lu [Fri, 19 Jan 2018 17:50:00 +0000 (09:50 -0800)]
x86-64: Properly align La_x86_64_retval to VEC_SIZE [BZ #22715]
_dl_runtime_profile calls _dl_call_pltexit, passing a pointer to
La_x86_64_retval which is allocated on stack. The lrv_vector0
field in La_x86_64_retval must be aligned to size of vector register.
When allocating stack space for La_x86_64_retval, we need to make sure
that the address of La_x86_64_retval + RV_VECTOR0_OFFSET is aligned to
VEC_SIZE. This patch checks the alignment of the lrv_vector0 field
and pads the stack space if needed.
Tested with x32 and x86-64 on SSE4, AVX and AVX512 machines. It fixed
I verified that without the guard accounting change in commit 630f4cc3aa019ede55976ea561f1a7af2f068639 (Fix stack guard size
accounting) and RTLD_NOW for libgcc_s introduced by commit f993b8754080ac7572b692870e926d8b493db16c (nptl: Open libgcc.so with
RTLD_NOW during pthread_cancel), the tst-minstack-cancel test fails on
an AVX-512F machine. tst-minstack-exit still passes, and either of
the mentioned commit by itself frees sufficient stack space to make
tst-minstack-cancel pass, too.
Szabolcs Nagy [Mon, 15 Jan 2018 15:06:31 +0000 (16:06 +0100)]
[BZ #22637] Fix stack guard size accounting
Previously if user requested S stack and G guard when creating a
thread, the total mapping was S and the actual available stack was
S - G - static_tls, which is not what the user requested.
This patch fixes the guard size accounting by pretending the user
requested S+G stack. This way all later logic works out except
when reporting the user requested stack size (pthread_getattr_np)
or when computing the minimal stack size (__pthread_get_minstack).
Normally this will increase thread stack allocations by one page.
TLS accounting is not affected, that will require a separate fix.
Florian Weimer [Mon, 8 Jan 2018 13:57:25 +0000 (14:57 +0100)]
nptl: Add test for callee-saved register restore in pthread_exit
GCC PR 83641 results in a miscompilation of libpthread, which
causes pthread_exit not to restore callee-saved registers before
running destructors for objects on the stack. This test detects
this situation:
info: unsigned int, direct pthread_exit call
tst-thread-exit-clobber.cc:80: numeric comparison failure
left: 4148288912 (0xf741dd90); from: value
right: 1600833940 (0x5f6ac994); from: magic_values.v2
info: double, direct pthread_exit call
info: unsigned int, indirect pthread_exit call
info: double, indirect pthread_exit call
error: 1 test failures
Dmitry V. Levin [Sun, 7 Jan 2018 02:03:41 +0000 (02:03 +0000)]
linux: make getcwd(3) fail if it cannot obtain an absolute path [BZ #22679]
Currently getcwd(3) can succeed without returning an absolute path
because the underlying getcwd syscall, starting with linux commit
v2.6.36-rc1~96^2~2, may succeed without returning an absolute path.
This is a conformance issue because "The getcwd() function shall
place an absolute pathname of the current working directory
in the array pointed to by buf, and return buf".
This is also a security issue because a non-absolute path returned
by getcwd(3) causes a buffer underflow in realpath(3).
Fix this by checking the path returned by getcwd syscall and falling
back to generic_getcwd if the path is not absolute, effectively making
getcwd(3) fail with ENOENT. The error code is chosen for consistency
with the case when the current directory is unlinked.
[BZ #22679]
CVE-2018-1000001
* sysdeps/unix/sysv/linux/getcwd.c (__getcwd): Fall back to
generic_getcwd if the path returned by getcwd syscall is not absolute.
* io/tst-getcwd-abspath.c: New test.
* io/Makefile (tests): Add tst-getcwd-abspath.
Joseph Myers [Tue, 22 Aug 2017 00:30:51 +0000 (00:30 +0000)]
Fix position of tests-unsupported definition in assert/Makefile.
tests-unsupported has to be defined before the inclusion of Rules in a
subdirectory Makefile; otherwise it is ineffective. This patch fixes
the ordering in assert/Makefile, where a recent test addition put
tests-unsupported too late (resulting in build failures when the C++
compiler was missing or broken, and thereby showing up the unrelated
bug 21987).
Incidentally, I don't see why these tests depend on
$(have-cxx-thread_local) rather than just a working C++ compiler.
Tested in such a configuration (broken compiler/libstdc++) with
build-many-glibcs.py.
Florian Weimer [Wed, 21 Jun 2017 20:43:57 +0000 (22:43 +0200)]
Implement allocation buffers for internal use
This commit adds fixed-size allocation buffers. The primary use
case is in NSS modules, where dynamically sized data is stored
in a fixed-size buffer provided by the caller.
Other uses include a replacement of mempcpy cascades (which is
safer due to the size checking inherent to allocation buffers).
Florian Weimer [Fri, 2 Jun 2017 09:59:28 +0000 (11:59 +0200)]
Add internal facility for dynamic array handling
This is intended as a type-safe alternative to obstacks and
hand-written realloc constructs. The implementation avoids
writing function pointers to the heap.
Florian Weimer [Thu, 4 Jan 2018 11:32:36 +0000 (12:32 +0100)]
getaddrinfo: Fix error handling in gethosts [BZ #21915] [BZ #21922]
The old code uses errno as the primary indicator for success or
failure. This is wrong because errno is only set for specific
combinations of the status return value and the h_errno variable.
This simplifies the code because it is not necessary to propagate the
temporary h_errno value to the thread-local variable. It also increases
compatibility with NSS modules which update only one of the two places.
Florian Weimer [Thu, 11 May 2017 09:32:16 +0000 (11:32 +0200)]
support_format_addrinfo: Fix flags and canonname formatting
The address family splitting via format_ai_family made unpredictable
the place where the canonname field was printed. This commit adjusts
the implementation so that the ai_flags is checked for consistency
across the list, and ai_canonname must only be present on the first
list element.
Tests for AI_CANONNAME are added to resolv/tst-resolv-basic.
Florian Weimer [Thu, 4 Jan 2018 10:45:20 +0000 (11:45 +0100)]
resolv: Support an exactly sized buffer in ns_name_pack [BZ #21359]
This bug did not affect name resolution because those functions
indirectly call ns_name_pack with a buffer which is always larger
than the generated query packet, even in the case of the
longest-possible domain name.
Florian Weimer [Fri, 2 Jun 2017 12:54:56 +0000 (14:54 +0200)]
getaddrinfo: Always allocate canonical name on the heap
A further simplification could eliminate the canon variable in
gaih_inet and replace it with canonbuf. However, canonbuf is
used as a flag in the nscd code, which makes this somewhat
non-straightforward.
Aurelien Jarno [Sat, 30 Dec 2017 09:54:23 +0000 (10:54 +0100)]
elf: Check for empty tokens before dynamic string token expansion [BZ #22625]
The fillin_rpath function in elf/dl-load.c loops over each RPATH or
RUNPATH tokens and interprets empty tokens as the current directory
("./"). In practice the check for empty token is done *after* the
dynamic string token expansion. The expansion process can return an
empty string for the $ORIGIN token if __libc_enable_secure is set
or if the path of the binary can not be determined (/proc not mounted).
Fix that by moving the check for empty tokens before the dynamic string
token expansion. In addition, check for NULL pointer or empty strings
return by expand_dynamic_string_token.
The above changes highlighted a bug in decompose_rpath, an empty array
is represented by the first element being NULL at the fillin_rpath
level, but by using a -1 pointer in decompose_rpath and other functions.
Changelog:
[BZ #22625]
* elf/dl-load.c (fillin_rpath): Check for empty tokens before dynamic
string token expansion. Check for NULL pointer or empty string possibly
returned by expand_dynamic_string_token.
(decompose_rpath): Check for empty path after dynamic string
token expansion.
(cherry picked from commit 3e3c904daef69b8bf7d5cc07f793c9f07c3553ef)
Dmitry V. Levin [Sun, 17 Dec 2017 23:49:46 +0000 (23:49 +0000)]
elf: do not substitute dst in $LD_LIBRARY_PATH twice [BZ #22627]
Starting with commit glibc-2.18.90-470-g2a939a7e6d81f109d49306bc2e10b4ac9ceed8f9 that
introduced substitution of dynamic string tokens in fillin_rpath,
_dl_init_paths invokes _dl_dst_substitute for $LD_LIBRARY_PATH twice:
the first time it's called directly, the second time the result
is passed on to fillin_rpath which calls expand_dynamic_string_token
which in turn calls _dl_dst_substitute, leading to the following
behaviour:
$ mkdir -p /tmp/'$ORIGIN' && cd /tmp/'$ORIGIN' &&
echo 'int main(){}' |gcc -xc - &&
strace -qq -E LD_LIBRARY_PATH='$ORIGIN' -e /open ./a.out
open("/tmp//tmp/$ORIGIN/tls/x86_64/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/tmp//tmp/$ORIGIN/tls/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/tmp//tmp/$ORIGIN/x86_64/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/tmp//tmp/$ORIGIN/libc.so.6", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
Fix this by removing the direct _dl_dst_substitute invocation.
* elf/dl-load.c (_dl_init_paths): Remove _dl_dst_substitute preparatory
code and invocation.
James Clarke [Tue, 12 Dec 2017 14:17:10 +0000 (12:17 -0200)]
ia64: Add ipc_priv.h header to set __IPC_64 to zero
When running strace, IPC_64 was set in the command, but ia64 is
an architecture where CONFIG_ARCH_WANT_IPC_PARSE_VERSION *isn't* set
in the kernel, so ipc_parse_version just returns IPC_64 without
clearing the IPC_64 bit in the command.
* sysdeps/unix/sysv/linux/ia64/ipc_priv.h: New file defining
__IPC_64 to 0 to avoid IPC_64 being set.
This patch syncs posix/glob.c implementation with gnulib version b5ec983 (glob: simplify symlink detection). The only difference
to gnulib code is
* DT_UNKNOWN, DT_DIR, and DT_LNK definition in the case there
were not already defined. Gnulib code which uses
HAVE_STRUCT_DIRENT_D_TYPE will redefine them wrongly because
GLIBC does not define HAVE_STRUCT_DIRENT_D_TYPE. Instead
the patch check for each definition instead.
Also, the patch requires additional globfree and globfree64 files
for compatibility version on some architectures. Also the code
simplification leads to not macro simplification (not need for
NO_GLOB_PATTERN_P anymore).
Checked on x86_64-linux-gnu and on a build using build-many-glibcs.py
for all major architectures.
[BZ #1062]
* posix/Makefile (routines): Add globfree, globfree64, and
glob_pattern_p.
* posix/flexmember.h: New file.
* posix/glob_internal.h: Likewise.
* posix/glob_pattern_p.c: Likewise.
* posix/globfree.c: Likewise.
* posix/globfree64.c: Likewise.
* sysdeps/gnu/globfree64.c: Likewise.
* sysdeps/unix/sysv/linux/alpha/globfree.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/globfree64.c: Likewise.
* sysdeps/unix/sysv/linux/oldglob.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/globfree64.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/globfree.c: Likewise.
* sysdeps/wordsize-64/globfree.c: Likewise.
* sysdeps/wordsize-64/globfree64.c: Likewise.
* posix/glob.c (HAVE_CONFIG_H): Use !_LIBC instead.
[NDEBUG): Remove comments.
(GLOB_ONLY_P, _AMIGA, VMS): Remove define.
(dirent_type): New type. Use uint_fast8_t not
uint8_t, as C99 does not require uint8_t.
(DT_UNKNOWN, DT_DIR, DT_LNK): New macros.
(struct readdir_result): Use dirent_type. Do not define skip_entry
unless it is needed; this saves a byte on platforms lacking d_ino.
(readdir_result_type, readdir_result_skip_entry):
New functions, replacing ...
(readdir_result_might_be_symlink, readdir_result_might_be_dir):
these functions, which were removed. This makes the callers
easier to read. All callers changed.
(D_INO_TO_RESULT): Now empty if there is no d_ino.
(size_add_wrapv, glob_use_alloca): New static functions.
(glob, glob_in_dir): Check for size_t overflow in several places,
and fix some size_t checks that were not quite right.
Remove old code using SHELL since Bash no longer
uses this.
(glob, prefix_array): Separate MS code better.
(glob_in_dir): Remove old Amiga and VMS code.
(globfree, __glob_pattern_type, __glob_pattern_p): Move to
separate files.
(glob_in_dir): Do not rely on undefined behavior in accessing
struct members beyond their bounds. Use a flexible array member
instead
(link_stat): Rename from link_exists2_p and return -1/0 instead of
0/1. Caller changed.
(glob): Fix memory leaks.
* posix/glob64 (globfree64): Move to separate file.
* sysdeps/gnu/glob64.c (NO_GLOB_PATTERN_P): Remove define.
(globfree64): Remove hidden alias.
* sysdeps/unix/sysv/linux/Makefile (sysdeps_routines): Add
oldglob.
* sysdeps/unix/sysv/linux/alpha/glob.c (__new_globfree): Move to
separate file.
* sysdeps/unix/sysv/linux/i386/glob64.c (NO_GLOB_PATTERN_P): Remove
define.
Move compat code to separate file.
* sysdeps/wordsize-64/glob.c (globfree): Move definitions to
separate file.
posix: Do not use WNOHANG in waitpid call for Linux posix_spawn
As shown in some buildbot issues on aarch64 and powerpc, calling
clone (VFORK) and waitpid (WNOHANG) does not guarantee the child
is ready to be collected. This patch changes the call back to 0
as before fe05e1cb6d64 fix.
This change can lead to the scenario 4.3 described in the commit,
where the waitpid call can hang undefinitely on the call. However
this is also a very unlikely and also undefinied situation where
both the caller is trying to terminate a pid before posix_spawn
returns and the race pid reuse is triggered. I don't see how to
correct handle this specific situation within posix_spawn.
Checked on x86_64-linux-gnu, aarch64-linux-gnu and
powerpc64-linux-gnu.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Use 0 instead of
WNOHANG in waitpid call.
posix: Fix improper assert in Linux posix_spawn (BZ#22273)
As noted by Florian Weimer, current Linux posix_spawn implementation
can trigger an assert if the auxiliary process is terminated before
actually setting the err member:
340 /* Child must set args.err to something non-negative - we rely on
341 the parent and child sharing VM. */
342 args.err = -1;
[...]
362 new_pid = CLONE (__spawni_child, STACK (stack, stack_size), stack_size,
363 CLONE_VM | CLONE_VFORK | SIGCHLD, &args);
364
365 if (new_pid > 0)
366 {
367 ec = args.err;
368 assert (ec >= 0);
Another possible issue is killing the child between setting the err and
actually calling execve. In this case the process will not ran, but
posix_spawn also will not report any error:
As suggested by Andreas Schwab, this patch removes the faulty assert
and also handles any signal that happens before fork and execve as the
spawn was successful (and thus relaying the handling to the caller to
figure this out). Different than Florian, I can not see why using
atomics to set err would help here, essentially the code runs
sequentially (due CLONE_VFORK) and I think it would not be legal the
compiler evaluate ec without checking for new_pid result (thus there
is no need to compiler barrier).
Summarizing the possible scenarios on posix_spawn execution, we
have:
1. For default case with a success execution, args.err will be 0, pid
will not be collected and it will be reported to caller.
2. For default failure case, args.err will be positive and the it will
be collected by the waitpid. An error will be reported to the
caller.
3. For the unlikely case where the process was terminated and not
collected by a caller signal handler, it will be reported as succeful
execution and not be collected by posix_spawn (since args.err will
be 0). The caller will need to actually handle this case.
4. For the unlikely case where the process was terminated and collected
by caller we have 3 other possible scenarios:
4.1. The auxiliary process was terminated with args.err equal to 0:
it will handled as 1. (so it does not matter if we hit the pid
reuse race since we won't possible collect an unexpected
process).
4.2. The auxiliary process was terminated after execve (due a failure
in calling it) and before setting args.err to -1: it will also
be handle as 1. but with the issue of not be able to report the
caller a possible execve failures.
4.3. The auxiliary process was terminated after args.err is set to -1:
this is the case where it will be possible to hit the pid reuse
case where we will need to collected the auxiliary pid but we
can not be sure if it will be expected one. I think for this
case we need to actually change waitpid to use WNOHANG to avoid
hanging indefinitely on the call and report an error to caller
since we can't differentiate between a default failure as 2.
and a possible pid reuse race issue.
Checked on x86_64-linux-gnu.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Handle the case where
the auxiliary process is terminated by a signal before calling _exit
or execve.
Andreas Schwab [Tue, 8 Aug 2017 14:21:58 +0000 (16:21 +0200)]
Don't use IFUNC resolver for longjmp or system in libpthread (bug 21041)
Unlike the vfork forwarder and like the fork forwarder as in bug 19861,
there won't be a problem when the compiler does not turn this into a tail
call.
James Clarke [Fri, 13 Oct 2017 18:44:39 +0000 (15:44 -0300)]
Fix TLS relocations against local symbols on powerpc32, sparc32 and sparc64
Normally, TLS relocations against local symbols are optimised by the linker
to be absolute. However, gold does not do this, and so it is possible to
end up with, for example, R_SPARC_TLS_DTPMOD64 referring to a local symbol.
Since sym_map is left as null in elf_machine_rela for the special local
symbol case, the relocation handling thinks it has nothing to do, and so
the module gets left as 0. Havoc then ensues when the variable in question
is accessed.
Before this fix, the main_local_gold program would receive a SIGBUS on
sparc64, and SIGSEGV on powerpc32. With this fix applied, that test now
passes like the rest of them.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela):
Assign sym_map to be map for local symbols, as TLS relocations
use sym_map to determine whether the symbol is defined and to
extract the TLS information.
* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela): Likewise.
Joseph Myers [Thu, 19 Oct 2017 17:32:20 +0000 (17:32 +0000)]
Install correct bits/long-double.h for MIPS64 (bug 22322).
Similar to bug 21987 for SPARC, MIPS64 wrongly installs the ldbl-128
version of bits/long-double.h, meaning incorrect results when using
headers installed from a 64-bit installation for a 32-bit build. (I
haven't actually seen this cause build failures before its interaction
with bits/floatn.h did so - installed headers wrongly expecting
_Float128 to be available in a 32-bit configuration.)
This patch fixes the bug by moving the MIPS header to
sysdeps/mips/ieee754, which comes before sysdeps/ieee754/ldbl-128 in
the sysdeps directory ordering. (bits/floatn.h will need a similar
fix - duplicating the ldbl-128 version for MIPS will suffice - for
headers from a 32-bit installation to be correct for 64-bit builds.)
Tested with build-many-glibcs.py (compilers build for
mips64-linux-gnu, where there was previously a libstdc++ build failure
as at
<https://sourceware.org/ml/libc-testresults/2017-q4/msg00130.html>).
H.J. Lu [Sun, 22 Oct 2017 15:20:38 +0000 (08:20 -0700)]
x86-64: Use fxsave/xsave/xsavec in _dl_runtime_resolve [BZ #21265]
In _dl_runtime_resolve, use fxsave/xsave/xsavec to preserve all vector,
mask and bound registers. It simplifies _dl_runtime_resolve and supports
different calling conventions. ld.so code size is reduced by more than
1 KB. However, use fxsave/xsave/xsavec takes a little bit more cycles
than saving and restoring vector and bound registers individually.
Latency for _dl_runtime_resolve to lookup the function, foo, from one
shared library plus libc.so:
This is the worst case where portion of time spent for saving and
restoring registers is bigger than majority of cases. With smaller
_dl_runtime_resolve code size, overall performance impact is negligible.
On IvyBridge, differences in build and test time of binutils with lazy
binding GCC and binutils are noises. On Westmere, differences in
bootstrap and "makc check" time of GCC 7 with lazy binding GCC and
binutils are also noises.
H.J. Lu [Thu, 19 Oct 2017 15:47:38 +0000 (08:47 -0700)]
x86-64: Verify that _dl_runtime_resolve preserves vector registers
On x86-64, _dl_runtime_resolve must preserve the first 8 vector
registers. Add 3 _dl_runtime_resolve tests to verify that SSE,
AVX and AVX512 registers are preserved.
Refactor long double information into bits/long-double.h.
resulted in sparc32 configurations installing the ldbl-opt version of
bits/long-double.h instead of the intended
sysdeps/unix/sysv/linux/sparc version.
For sparc32 by itself, this is not a problem, since the ldbl-opt
version is correct for sparc32. However, both sparc32 and sparc64 are
supposed to install sets of headers that work for both of them, so
that a single sysroot, whichever order the libraries are built and
installed in, works for both. The effect of having the wrong version
installed is that you end up with a miscompiled sparc64 libstdc++
which fails glibc's configure tests for the C++ compiler.
This patch moves the header from sysdeps/unix/sysv/linux/sparc to
separate copies of the same file for sparc32 and sparc64, to ensure it
comes before ldbl-opt in the sysdeps directory ordering.
Tested with build-many-glibcs.py for sparc64-linux-gnu and
sparcv9-linux-gnu.
[BZ #21987]
* sysdeps/unix/sysv/linux/sparc/bits/long-double.h: Remove file
and copy to ...
* sysdeps/unix/sysv/linux/sparc/sparc32/bits/long-double.h:
... here.
* sysdeps/unix/sysv/linux/sparc/sparc64/bits/long-double.h:
... and here.
H.J. Lu [Mon, 11 Sep 2017 16:04:57 +0000 (09:04 -0700)]
Make copy of <bits/std_abs.h> from GCC 7 [BZ #21573]
<bits/std_abs.h> from GCC 7 will include /usr/include/stdlib.h from
"#include_next" (instead of stdlib/stdlib.h in the glibc source
directory), and this turns up as a make dependency. Also make a copy
of <bits/std_abs.h> to prevent it from including /usr/include/stdlib.h.
H.J. Lu [Mon, 11 Sep 2017 15:51:52 +0000 (08:51 -0700)]
string/stratcliff.c: Replace int with size_t [BZ #21982]
Fix GCC 7 errors when string/stratcliff.c is compiled with -O3:
stratcliff.c: In function ‘do_test’:
cc1: error: assuming signed overflow does not occur when assuming that (X - c) <= X is always true [-Werror=strict-overflow]
[BZ #21982]
* string/stratcliff.c (do_test): Declare size, nchars, inner,
middle and outer with size_t instead of int. Repleace %d and
%Zd with %zu in printf. Update "MAX (0, nchars - 128)" and
"MAX (outer, nchars - 64)" to support unsigned outer and
nchars. Also exit loop when outer == 0.
H.J. Lu [Thu, 31 Aug 2017 13:28:31 +0000 (06:28 -0700)]
Place $(elf-objpfx)sofini.os last [BZ #22051]
Since sofini.os terminates .eh_frame section, it should be placed last.
[BZ #22051]
* Makerules (build-module-helper-objlist): Filter out
$(elf-objpfx)sofini.os.
(build-shlib-objlist): Append $(elf-objpfx)sofini.os if it is
needed.
Carlos O'Donell [Sat, 29 Jul 2017 04:02:03 +0000 (00:02 -0400)]
mutex: Fix robust mutex lock acquire (Bug 21778)
65810f0ef05e8c9e333f17a44e77808b163ca298 fixed a robust mutex bug but
introduced BZ 21778: if the CAS used to try to acquire a lock fails, the
expected value is not updated, which breaks other cases in the loce
acquisition loop. The fix is to simply update the expected value with
the value returned by the CAS, which ensures that behavior is as if the
first case with the CAS never happened (if the CAS fails).
This is a regression introduced in the last release.
Tested on x86_64, i686, ppc64, ppc64le, s390x, aarch64, armv7hl.
Carlos O'Donell [Mon, 28 Aug 2017 13:04:39 +0000 (15:04 +0200)]
rwlock: Fix explicit hand-over (bug 21298)
Without this fix, the rwlock can fail to execute the explicit hand-over
in certain cases (e.g., empty critical sections that switch quickly between
read and write phases). This can then lead to errors in how __wrphase_futex
is accessed, which in turn can lead to deadlocks.