Mahesh Bodapati [Fri, 11 Aug 2023 15:38:25 +0000 (10:38 -0500)]
string: Fix tester build with fortify enable with gcc < 12
When building with fortify enabled, GCC < 12 issues a warning on the
fortify strncat wrapper might overflow the destination buffer (the
failure is tied to -Werror).
Checked on ppc64 and x86_64. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
(cherry picked from commit f1c7ed0859a45929136836341741c7cd70f428cb)
Andreas Schwab [Tue, 1 Aug 2023 15:01:37 +0000 (17:01 +0200)]
iconv: restore verbosity with unrecognized encoding names (bug 30694)
Commit 91927b7c76 ("Rewrite iconv option parsing [BZ #19519]") changed the
iconv program to call __gconv_open directly instead of the iconv_open
wrapper, but the former does not set errno. Update the caller to
interpret the return codes like iconv_open does.
getaddrinfo: Fix use after free in getcanonname (CVE-2023-4806)
When an NSS plugin only implements the _gethostbyname2_r and
_getcanonname_r callbacks, getaddrinfo could use memory that was freed
during tmpbuf resizing, through h_name in a previous query response.
The backing store for res->at->name when doing a query with
gethostbyname3_r or gethostbyname2_r is tmpbuf, which is reallocated in
gethosts during the query. For AF_INET6 lookup with AI_ALL |
AI_V4MAPPED, gethosts gets called twice, once for a v6 lookup and second
for a v4 lookup. In this case, if the first call reallocates tmpbuf
enough number of times, resulting in a malloc, th->h_name (that
res->at->name refers to) ends up on a heap allocated storage in tmpbuf.
Now if the second call to gethosts also causes the plugin callback to
return NSS_STATUS_TRYAGAIN, tmpbuf will get freed, resulting in a UAF
reference in res->at->name. This then gets dereferenced in the
getcanonname_r plugin call, resulting in the use after free.
Fix this by copying h_name over and freeing it at the end. This
resolves BZ #30843, which is assigned CVE-2023-4806.
CVE-2023-4527: Stack read overflow with large TCP responses in no-aaaa mode
Without passing alt_dns_packet_buffer, __res_context_search can only
store 2048 bytes (what fits into dns_packet_buffer). However,
the function returns the total packet size, and the subsequent
DNS parsing code in _nss_dns_gethostbyname4_r reads beyond the end
of the stack-allocated buffer.
When backporting commmit 6985865bc3ad5b23147ee73466583dd7fdf65892
("elf: Always call destructors in reverse constructor order
(bug 30785)"), we can move the l_init_called_next field to this
place, so that the internal GLIBC_PRIVATE ABI does not change.
Reviewed-by: Carlos O'Donell <carlos@redhat.com> Tested-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 53df2ce6885da3d0e89e87dca7b095622296014f)
elf: Always call destructors in reverse constructor order (bug 30785)
The current implementation of dlclose (and process exit) re-sorts the
link maps before calling ELF destructors. Destructor order is not the
reverse of the constructor order as a result: The second sort takes
relocation dependencies into account, and other differences can result
from ambiguous inputs, such as cycles. (The force_first handling in
_dl_sort_maps is not effective for dlclose.) After the changes in
this commit, there is still a required difference due to
dlopen/dlclose ordering by the application, but the previous
discrepancies went beyond that.
A new global (namespace-spanning) list of link maps,
_dl_init_called_list, is updated right before ELF constructors are
called from _dl_init.
In dl_close_worker, the maps variable, an on-stack variable length
array, is eliminated. (VLAs are problematic, and dlclose should not
call malloc because it cannot readily deal with malloc failure.)
Marking still-used objects uses the namespace list directly, with
next and next_idx replacing the done_index variable.
After marking, _dl_init_called_list is used to call the destructors
of now-unused maps in reverse destructor order. These destructors
can call dlopen. Previously, new objects do not have l_map_used set.
This had to change: There is no copy of the link map list anymore,
so processing would cover newly opened (and unmarked) mappings,
unloading them. Now, _dl_init (indirectly) sets l_map_used, too.
(dlclose is handled by the existing reentrancy guard.)
After _dl_init_called_list traversal, two more loops follow. The
processing order changes to the original link map order in the
namespace. Previously, dependency order was used. The difference
should not matter because relocation dependencies could already
reorder link maps in the old code.
The changes to _dl_fini remove the sorting step and replace it with
a traversal of _dl_init_called_list. The l_direct_opencount
decrement outside the loader lock is removed because it appears
incorrect: the counter manipulation could race with other dynamic
loader operations.
tst-audit23 needs adjustments to the changes in LA_ACT_DELETE
notifications. The new approach for checking la_activity should
make it clearer that la_activty calls come in pairs around namespace
updates.
The dependency sorting test cases need updates because the destructor
order is always the opposite order of constructor order, even with
relocation dependencies or cycles present.
There is a future cleanup opportunity to remove the now-constant
force_first and for_fini arguments from the _dl_sort_maps function.
Adam Jackson [Fri, 8 Sep 2023 19:55:19 +0000 (15:55 -0400)]
libio: Fix oversized __io_vtables
IO_VTABLES_LEN is the size of the struct array in bytes, not the number
of __IO_jump_t's in the array. Drops just under 384kb from .rodata on
LP64 machines.
Fixes: 3020f72618e ("libio: Remove the usage of __libc_IO_vtables") Signed-off-by: Adam Jackson <ajax@redhat.com> Reviewed-by: Florian Weimer <fweimer@redhat.com> Tested-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit 8cb69e054386f980f9ff4d93b157861d72b2019e)
Aurelien Jarno [Mon, 28 Aug 2023 21:30:37 +0000 (23:30 +0200)]
io: Fix record locking contants for powerpc64 with __USE_FILE_OFFSET64
Commit 5f828ff824e3b7cd1 ("io: Fix F_GETLK, F_SETLK, and F_SETLKW for
powerpc64") fixed an issue with the value of the lock constants on
powerpc64 when not using __USE_FILE_OFFSET64, but it ended-up also
changing the value when using __USE_FILE_OFFSET64 causing an API change.
Fix that by also checking that define, restoring the pre 4d0fe291aed3a476a commit values:
SYS_modify_ldt requires CONFIG_MODIFY_LDT_SYSCALL to be set in the kernel, which
some distributions may disable for hardening. Check if that's the case (unset)
and mark the test as UNSUPPORTED if so.
Florian Weimer [Thu, 10 Aug 2023 17:36:56 +0000 (19:36 +0200)]
malloc: Remove bin scanning from memalign (bug 30723)
On the test workload (mpv --cache=yes with VP9 video decoding), the
bin scanning has a very poor success rate (less than 2%). The tcache
scanning has about 50% success rate, so keep that.
Update comments in malloc/tst-memalign-2 to indicate the purpose
of the tests. Even with the scanning removed, the additional
merging opportunities since commit 542b1105852568c3ebc712225ae78b
("malloc: Enable merging of remainders in memalign (bug 30723)")
are sufficient to pass the existing large bins test.
Remove leftover variables from _int_free from refactoring in the
same commit.
Florian Weimer [Fri, 11 Aug 2023 09:18:17 +0000 (11:18 +0200)]
malloc: Enable merging of remainders in memalign (bug 30723)
Previously, calling _int_free from _int_memalign could put remainders
into the tcache or into fastbins, where they are invisible to the
low-level allocator. This results in missed merge opportunities
because once these freed chunks become available to the low-level
allocator, further memalign allocations (even of the same size are)
likely obstructing merges.
Furthermore, during forwards merging in _int_memalign, do not
completely give up when the remainder is too small to serve as a
chunk on its own. We can still give it back if it can be merged
with the following unused chunk. This makes it more likely that
memalign calls in a loop achieve a compact memory layout,
independently of initial heap layout.
Drop some useless (unsigned long) casts along the way, and tweak
the style to more closely match GNU on changed lines.
Since i686 provides the fortified wrappers for memcpy, mempcpy,
memmove, and memset on the same string implementation, the static
build tries to optimized it by not tying the fortified wrappers
to string routine (to avoid pulling the fortify function if
they are not required).
Checked on i686-linux-gnu building with different option:
default and --disable-multi-arch plus default, --disable-default-pie,
--enable-fortify-source={2,3}, and --enable-fortify-source={2,3}
with --disable-default-pie. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit c73c96a4a1af1326df7f96eec58209e1e04066d8)
x86_64: Fix build with --disable-multiarch (BZ 30721)
With multiarch disabled, the default memmove implementation provides
the fortify routines for memcpy, mempcpy, and memmove. However, it
does not provide the internal hidden definitions used when building
with fortify enabled. The memset has a similar issue.
Checked on x86_64-linux-gnu building with different options:
default and --disable-multi-arch plus default, --disable-default-pie,
--enable-fortify-source={2,3}, and --enable-fortify-source={2,3}
with --disable-default-pie. Tested-by: Andreas K. Huettel <dilfridge@gentoo.org> Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 51cb52214fcd72849c640b12f5099ed3ac776181)
Florian Weimer [Fri, 11 Aug 2023 08:10:16 +0000 (10:10 +0200)]
nscd: Do not rebuild getaddrinfo (bug 30709)
The nscd daemon caches hosts data from NSS modules verbatim, without
filtering protocol families or sorting them (otherwise separate caches
would be needed for certain ai_flags combinations). The cache
implementation is complete separate from the getaddrinfo code. This
means that rebuilding getaddrinfo is not needed. The only function
actually used is __bump_nl_timestamp from check_pf.c, and this change
moves it into nscd/connections.c.
Tested on x86_64-linux-gnu with -fexceptions, built with
build-many-glibcs.py. I also backported this patch into a distribution
that still supports nscd and verified manually that caching still works.
x86: Fix for cache computation on AMD legacy cpus.
Some legacy AMD CPUs and hypervisors have the _cpuid_ '0x8000_001D'
set to Zero, thus resulting in zeroed-out computed cache values.
This patch reintroduces the old way of cache computation as a
fail-safe option to handle these exceptions.
Fixed 'level4_cache_size' value through handle_amd().
Florian Weimer [Tue, 1 Aug 2023 08:27:15 +0000 (10:27 +0200)]
stdlib: Improve tst-realpath compatibility with source fortification
On GCC before 11, IPA can make the fortified realpath aware that the
buffer size is not large enough (8 bytes instead of PATH_MAX bytes).
Fix this by using a buffer that is large enough.
string: Fix tester build with fortify enable with gcc 6
When building with fortify enabled, GCC 6 issues an warning the fortify
wrapper might overflow the destination buffer. However, GCC does not
provide a specific flag to disable the warning (the failure is tied to
-Werror). So to avoid disable all errors, only enable the check for
GCC 7 or newer.
Checked on i686-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
On __convert_scm_timestamps GCC 6 issues an warning that tvts[0]/tvts[1]
maybe be used uninitialized, however it would be used if type is set to a
value different than 0 (done by either COMPAT_SO_TIMESTAMP_OLD or
COMPAT_SO_TIMESTAMPNS_OLD) which will fallthrough to 'common' label.
It does not show with gcc 7 or more recent versions.
Checked on i686-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Similar to memcpy, mempcpy, and memmove there is no need for an
specific memset_chk-nonshared.S. It can be provided by
memset-ia32.S itself for static library.
Checked on i686-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Although is not an issue for normal static builds, with fortify=3
glibc itself might use the fortify chk functions and thus static
build might fail with multiple definitions. For instance:
x86_64-glibc-linux-gnu-gcc -m32 -march=i686 -o [...]math/test-signgam-uchar-static -nostdlib -nostartfiles -static -static-pie [...]
x86_64-glibc-linux-gnu/bin/ld: [...]/libc.a(mempcpy-ia32.o):
in function `__mempcpy_chk': [...]/glibc-git/string/../sysdeps/i386/i686/mempcpy.S:32: multiple definition of `__mempcpy_chk';
[...]/libc.a(mempcpy_chk-nonshared.o):[...]/debug/../sysdeps/i386/mempcpy_chk.S:28: first defined here
collect2: error: ld returned 1 exit status
make[2]: *** [../Rules:298:
There is no need for mem*-nonshared.S, the __mem*_chk routines
are already provided by the assembly routines.
Checked on i686-linux-gnu with gcc 13 built with fortify=1,2,3 and
without fortify. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
With gcc 11.3.1, building with -D_FORTIFY_SOURCE=2 shows:
In function ‘getgroups’,
inlined from ‘do_test’ at test-errno.c:129:12:
../misc/sys/cdefs.h:195:6: error: argument 1 value -1 is negative
[-Werror=stringop-overflow=]
195 | ? __ ## f ## _alias (__VA_ARGS__)
\
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../posix/bits/unistd.h:115:10: note: in expansion of macro
‘__glibc_fortify’
115 | return __glibc_fortify (getgroups, __size, sizeof (__gid_t),
| ^~~~~~~~~~~~~~~
../posix/bits/unistd.h: In function ‘do_test’:
../posix/bits/unistd-decl.h:135:28: note: in a call to function
‘__getgroups_alias’ declared with attribute ‘access (write_only, 2, 1)’
135 | extern int __REDIRECT_NTH (__getgroups_alias, (int __size,
__gid_t __list[]),
| ^~~~~~~~~~~~~~~~~
../misc/sys/cdefs.h:264:6: note: in definition of macro ‘__REDIRECT_NTH’
264 | name proto __asm__ (__ASMNAME (#alias)) __THROW
It builds fine with gcc 12 and gcc 13.
Checked on x86_64-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Old GCC might trigger the the comparison will always evaluate as ‘true’
warnig for static build:
set-freeres.c:87:14: error: the comparison will always evaluate as
‘true’ for the address of ‘__libc_getgrgid_freemem_ptr’ will never be
NULL [-Werror=address]
if (&__ptr != NULL) \
So add pragma weak for all affected usages.
Checked on x86_64 and i686 with gcc 6 and 13. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Now that we have a proper configure argument for F_S (--enable-fortify-source),
just drop this entirely, to avoid conflicting with e.g. detected --enable-fortify-source
finding F_S=3, then nscd's Makefile setting F_S=2, resulting in a build-failure
because of the redefinition.
Signed-off-by: Sam James <sam@gentoo.org> Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org> Reviewed-by: Andreas K. Hüttel <dilfridge@gentoo.org>
Stefan Liebler [Tue, 25 Jul 2023 09:34:30 +0000 (11:34 +0200)]
Include sys/rseq.h in tst-rseq-disable.c
Starting with commit 2c6b4b272e6b4d07303af25709051c3e96288f2d
"nptl: Unconditionally use a 32-byte rseq area", the testcase
misc/tst-rseq-disable is UNSUPPORTED as RSEQ_SIG is not defined.
The mentioned commit removes inclusion of sys/rseq.h in nptl/descr.h.
Thus just include sys/rseq.h in the tst-rseq-disable.c as also done
in tst-rseq.c and tst-rseq-nptl.c. Reviewed-by: Florian Weimer <fweimer@redhat.com>
If fortify is enabled, the truncated output warning is issued by
the wrapper itself:
In function ‘strncpy’,
inlined from ‘test_strncpy’ at tester.c:505:10:
../string/bits/string_fortified.h:95:10: error: ‘__builtin_strncpy’
destination unchanged after copying no bytes from a string of length 3
[-Werror=stringop-truncation]
95 | return __builtin___strncpy_chk (__dest, __src, __len,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
96 | __glibc_objsize (__dest));
| ~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../include/bits/string_fortified.h:1,
from ../string/string.h:548,
from ../include/string.h:60,
from tester.c:33,
from inl-tester.c:6:
In function ‘strncpy’,
inlined from ‘test_strncpy’ at tester.c:505:10:
Checked on x86_64-linux-gnu. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
nscd: Use errval, not errno to guide cache update (bug 30662)
The errno variable is potentially clobbered by the preceding
send call. It is not related to the to-be-cached information.
The parallel code in hstcache.c and servicescache.c already uses
errval.
Ying Huang [Thu, 15 Jun 2023 07:50:21 +0000 (03:50 -0400)]
MIPS: Sync elf.h from binutils
Add new definitions for the MIPS target, specifically: relocation
types, machine flags, section type names, and object attribute tags
and values. On MIPS64, up to three relocations may be specified
within r_info, by the r_type, r_type2, and r_type3 fields, so add new
macros to get the respective reloc types for MIPS64.
If the kernel headers provide a larger struct rseq, we used that
size as the argument to the rseq system call. As a result,
rseq registration would fail on older kernels which only accept
size 32.
scripts: Fix fortify checks if compiler does not support _FORTIFY_SOURCE=3
The 30379efad1 added _FORTIFY_SOURCE checks without check if compiler
does support all used fortify levels. This patch fixes it by first
checking at configure time the maximum support fortify level and using
it instead of a pre-defined one.
We mentioned eventual dropping of libcrypt in the 2.28 NEWS. Actually
put that plan in motion by first disabling building libcrypt by default.
note in NEWS that the library will be dropped completely in a future
release.
Also add a couple of builds into build-many-glibcs.py.
Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> Reviewed-by: Andreas K. Hüttel <dilfridge@gentoo.org>
The _FORTIFY_SOURCE is used as default by some system compilers,
and there is no way to check if some fortify extension does not
trigger any conformance issue.
Based on feedback by Mike Gilbert <floppym@gentoo.org>
Linux-6.1.38-dist x86_64 AMD Phenom-tm- II X6 1055T Processor
-march=amdfam10
failures occur for x32 ABI
Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
Stefan Liebler [Thu, 13 Jul 2023 13:13:48 +0000 (15:13 +0200)]
Fix getting return address in elf/tst-audit28.c.
Starting with commit 1bcfe0f732066ae5336b252295591ebe7e51c301, the
test was enhanced and the object for __builtin_return_address (0)
is searched with _dl_find_object.
Unfortunately on e.g. s390 (31bit), a postprocessing step is needed
as the highest bit has to be masked out. This can be done with
__builtin_extract_return_addr.
Without this postprocessing, _dl_find_object returns with -1 and the
content of dlfo is invalid, which may lead to segfaults in basename.
Therefore those checks are now only done on success. Reviewed-by: Florian Weimer <fweimer@redhat.com>
[PATCH v1] x86: Use `3/4*sizeof(per-thread-L3)` as low bound for NT threshold.
On some machines we end up with incomplete cache information. This can
make the new calculation of `sizeof(total-L3)/custom-divisor` end up
lower than intended (and lower than the prior value). So reintroduce
the old bound as a lower bound to avoid potentially regressing code
where we don't have complete information to make the decision. Reviewed-by: DJ Delorie <dj@redhat.com>
x86: Increase `non_temporal_threshold` to roughly `sizeof_L3 / 4`
```
Split `shared` (cumulative cache size) from `shared_per_thread` (cache
size per socket), the `shared_per_thread` *can* be slightly off from
the previous calculation.
Previously we added `core` even if `threads_l2` was invalid, and only
used `threads_l2` to divide `core` if it was present. The changed
version only included `core` if `threads_l2` was valid.
This change restores the old behavior if `threads_l2` is invalid by
adding the entire value of `core`. Reviewed-by: DJ Delorie <dj@redhat.com>
Bump autoconf requirement to 2.71 to allow regenerating configure on
more recent distributions. autoconf 2.71 has been in Fedora since F36
and is the current version in Debian stable (bookworm). It appears to
be current in Gentoo as well.
All sysdeps configure and preconfigure scripts have also been
regenerated; all changes are trivial transformations that do not affect
functionality.
Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The sparc ABI has multiple cases on how to handle JMP_SLOT relocations,
(sparc_fixup_plt/sparc64_fixup_plt). For BINDNOW, _dl_audit_symbind
will be responsible to setup the final relocation value; while for
lazy binding _dl_fixup/_dl_profile_fixup will call the audit callback
and tail cail elf_machine_fixup_plt (which will call
sparc64_fixup_plt).
This patch fixes by issuing the SPARC specific routine on bindnow and
forwarding the audit value to elf_machine_fixup_plt for lazy resolution.
It fixes the la_symbind for bind-now tests on sparc64 and sparcv9:
This patch checks if assembler supports vector instructions to
generate LASX/LSX code or not, and then define HAVE_LOONGARCH_VEC_ASM macro
We have added support for vector instructions in binutils-2.41
See:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=75b2f521b101d974354f6ce9ed7c054d8b2e3b7a
sysdeps/s390: Exclude fortified routines from being built with _FORTIFY_SOURCE
Depending on build configuration, the [routine]-c.c files may be chosen
to provide fortified routines implementation. While [routines].c
implementation were automatically excluded, the [routines]-c.c ones were
not. This patch fixes that by adding these file to the list to be
filtered.
Carlos O'Donell [Fri, 7 Jul 2023 15:27:08 +0000 (11:27 -0400)]
Translations: Add new ro support and update others.
This brings in the new Romanian language translations, and updates
nine other translations. Important translations in this update
include the Italian and Japanese translations for ESTALE which
remove the mention of "NFS" from the error message translation.
realloc: Limit chunk reuse to only growing requests [BZ #30579]
The trim_threshold is too aggressive a heuristic to decide if chunk
reuse is OK for reallocated memory; for repeated small, shrinking
allocations it leads to internal fragmentation and for repeated larger
allocations that fragmentation may blow up even worse due to the dynamic
nature of the threshold.
Limit reuse only when it is within the alignment padding, which is 2 *
size_t for heap allocations and a page size for mmapped allocations.
There's the added wrinkle of THP, but this fix ignores it for now,
pessimizing that case in favor of keeping fragmentation low.
Some locales define a list of mapping pairs of alternate digits and
separators for input digits (to_inpunct). This require the scanf
to create a list of all possible inputs for the optional type
modifier 'I'.
Checked on x86_64-linux-gnu.
Reviewed-by: Joe Simmons-Talbott <josimmon@redhat.com>
fileops: Don't process ,ccs= as individual mode flags (BZ#18906)
In processing the first 7 individual characters of the mode for fopen
if ,ccs= is used those characters will be processed as well. Stop
processing individual mode flags once a comma is encountered. This has
the effect of requiring ,ccs= to be the last mode flag in the mode
string. Add a testcase to check that the ,ccs= mode flag is not
processed as individual mode flags.
Frédéric Bérat [Wed, 28 Jun 2023 07:07:26 +0000 (09:07 +0200)]
libio/bits/stdio2.h: Clearly separate declaration from definitions
Move declarations from libio/bits/stdio.h to existing
libio/bits/stdio2-decl.h. This will enable future use of
__REDIRECT_FORTIFY in place of some __REDIRECT.
misc/bits/syslog.h: Clearly separate declaration from definition
This allows to include bits/syslog-decl.h in include/sys/syslog.h and
therefore be able to create the libc_hidden_builtin_proto (__syslog_chk)
prototype.
misc/bits/select2.h: Clearly separate declaration from definitions
The __fdelt_chk declaration needs to be available so that
libc_hidden_proto can be used while not redefining __FD_ELT.
Thus, misc/bits/select-decl.h is created to hold the corresponding
prototypes.
posix/bits/unistd.h: Clearly separate declaration from definitions
This change is similar to what was done for bits/wchar2.h.
Routines declaration are moved into a dedicated bits/unistd-decl.h file
which is then included into the bits/unistd.h file.
This will allow to adapt the files so that PLT entries are not created when
_FORTIFY_SOURCE is enabled.
misc/sys/cdefs.h: Create FORTIFY redirects for internal calls
The __REDIRECT* macros are creating aliases which may lead to unwanted
PLT entries when fortification is enabled.
To prevent these entries, the REDIRECT alias should be set to point to the
existing __GI_* aliases.
This is done transparently by creating a __REDIRECT_FORTIFY* version of
these macros, that can be overwritten internally when necessary.
stdio: Ensure *_chk routines have their hidden builtin definition available
If libc_hidden_builtin_{def,proto} isn't properly set for *_chk routines,
there are unwanted PLT entries in libc.so.
There is a special case with __asprintf_chk:
If ldbl_* macros are used for asprintf, ABI gets broken on s390x,
if it isn't, ppc64le isn't building due to multiple asm redirections.
This is due to the inclusion of bits/stdio-lbdl.h for ppc64le whereas it
isn't for s390x. This header creates redirections, which are not
compatible with the ones generated using libc_hidden_def.
Yet, we can't use libc_hidden_ldbl_proto on s390x since it will not
create a simple strong alias (e.g. as done on x86_64), but a versioned
alias, leading to ABI breakage.
This results in errors on s390x:
/usr/bin/ld: glibc/iconv/../libio/bits/stdio2.h:137: undefined reference
to `__asprintf_chk'
projects / thirdparty / glibc.git / log
