Issue was we were expecting not matches with CHAR before the start of
the string in the page cross case.
The check code in the page cross case:
```
and $0xffffffffffffffc0,%rax
vmovdqa64 (%rax),%zmm17
vpcmpneqb %zmm17,%zmm16,%k1
vptestmb %zmm17,%zmm17,%k0{%k1}
kmovq %k0,%rax
inc %rax
shr %cl,%rax
je L(continue)
```
expects that all characters that neither match null nor CHAR will be
1s in `rax` prior to the `inc`. Then the `inc` will overflow all of
the 1s where no relevant match was found.
This is incorrect in the page-cross case, as the
`vmovdqa64 (%rax),%zmm17` loads from before the start of the input
string.
If there are matches with CHAR before the start of the string, `rax`
won't properly overflow.
The fix is quite simple. Just replace:
```
inc %rax
shr %cl,%rax
```
With:
```
sar %cl,%rax
inc %rax
```
The arithmetic shift will clear any matches prior to the start of the
string while maintaining the signbit so the 1s can properly overflow
to zero in the case of no matches.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Add string/test-strncmp-nonarray and
wcsmbs/test-wcsncmp-nonarray.
This is the test that uncovered bug 31934. Test run time
is more than one minute on a fairly current system, so turn
these into xtests that do not run automatically.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
It uses the same two-way algorithm used on strstr, strcasestr, and
memmem. Different than strstr, neither the "shift table" optimization
nor the self-adapting filtering check is used because it would result in
a too-large shift table (and it also simplifies the implementation bit).
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
Parametrize test-strstr.c so it can be used to check wcsstr.
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
It improve fortify checks for strcpy, stpcpy, strncpy, stpncpy, strcat,
strncat, strlcpy, and strlcat. The runtime and compile checks have
similar coverage as with GCC.
Checked on aarch64, armhf, x86_64, and i686.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
On s390x, I get warnings like this when do_one_test is inlined with SIZE_MAX:
In function ‘do_one_test’,
inlined from ‘do_overflow_tests’ at tst-strlcat2.c:184:2:
tst-strlcat2.c:49:18: error: ‘strnlen’ specified bound [18446744073709550866, 18446744073709551615] exceeds maximum object size 9223372036854775807 [-Werror=stringop-overflow=]
49 | # define STRNLEN strnlen
| ^
tst-strlcat2.c:89:23: note: in expansion of macro ‘STRNLEN’
89 | size_t dst_length = STRNLEN (dst, n);
| ^~~~~~~
This patch just marks the do_one_test function as noinline as also done in test-strncat.c:
Fix stringop-overflow warning in test-strncat.
https://sourceware.org/git/?p=glibc.git;a=commit;h=51aeab9a363a0d000d0912aa3d6490463a26fba2
WG14 decided to use the name C23 as the informal name of the next
revision of the C standard (notwithstanding the publication date in
2024). Update references to C2X in glibc to use the C23 name.
This is intended to update everything *except* where it involves
renaming files (the changes involving renaming tests are intended to
be done separately). In the case of the _ISOC2X_SOURCE feature test
macro - the only user-visible interface involved - support for that
macro is kept for backwards compatibility, while adding
_ISOC23_SOURCE.
Tested for x86_64.
For ports that use the default memset, the compiler might generate early
calls before the stack protector is initialized (for instance, riscv
with -fstack-protector-all on _dl_aux_init).
Checked on riscv64-linux-gnu-rv64imafdc-lp64d.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Seeing occasional failures in `__strchrnul_evex512` that are not
consistently reproducible. Hopefully by adding this the next failure
will provide enough information to debug.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
The prototype is:
void __memswap (void *restrict p1, void *restrict p2, size_t n)
The function swaps the content of two memory blocks P1 and P2 of
len N. Memory overlap is NOT handled.
It will be used on qsort optimization.
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
This patch implements comprehensive tests for strlcat/wcslcat
functions. Tests are mostly derived from strncat test suites
and modified to incorporate strlcat/wcslcat specifications.
Reviewed-by: DJ Delorie <dj@redhat.com>
This patch implements comprehensive tests for strlcpy/wcslcpy
functions. Tests are mostly derived from strncpy test suites
and modified to incorporate strlcpy/wcslcpy specifications.
Reviewed-by: DJ Delorie <dj@redhat.com>
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>
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>
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>
If fortify is enabled, the truncated output warning is issued by
the wrapper itself:
bug-strncat1.c: In function ‘main’:
bug-strncat1.c:14:3: error: ‘__builtin___strncat_chk’ output truncated
copying 1 byte from a string of length 2 [-Werror=stringop-truncation]
14 | strncat (d, "\5\6", 1);
| ^
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Since the _FORTIFY_SOURCE feature uses some routines of Glibc, they need to
be excluded from the fortification.
On top of that:
- some tests explicitly verify that some level of fortification works
appropriately, we therefore shouldn't modify the level set for them.
- some objects need to be build with optimization disabled, which
prevents _FORTIFY_SOURCE to be used for them.
Assembler files that implement architecture specific versions of the
fortified routines were not excluded from _FORTIFY_SOURCE as there is no
C header included that would impact their behavior.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
For strerror, this fixes commit 28aff04781 ("string:
Implement strerror in terms of strerror_l"). This commit avoids
returning NULL for strerror_l as well, although POSIX allows this
behavior for strerror_l.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
These functions are about to be added to POSIX, under Austin Group
issue 986.
The fortified strlcat implementation does not raise SIGABRT if the
destination buffer does not contain a null terminator, it just
inherits the non-failing regular strlcat behavior.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Copy strncpy tests for strndup. Covers some basic testcases with random
strings. Remove tests that set the destination's bytes and checked the
resulting buffer's bytes. Remove wide character test support since
wcsndup() doesn't exist.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Copy strcpy tests for strdup. Covers some basic testcases with random
strings. Add a zero-length string testcase.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Mark two variables as unused to silence warning when using
test-string.h for non-ifunc implementations.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
FreeBSD makes them available by default, too, so there does not seem
to be a reason to restrict these functions to _GNU_SOURCE.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Starting with commit
b2c474f8de
"x86: Fix strncat-avx2.S reading past length [BZ #30065]"
Building on s390 the test fails due warnings like:
In function ‘do_one_test’,
inlined from ‘do_overflow_tests’ at test-strncat.c:175:7:
test-strncat.c:31:18: error: ‘strnlen’ specified bound [4294966546, 4294967295] exceeds maximum object size 2147483647 [-Werror=stringop-overflow=]
31 | # define STRNLEN strnlen
| ^
test-strncat.c:83:16: note: in expansion of macro ‘STRNLEN’
83 | size_t len = STRNLEN (src, n);
| ^~~~~~~
In all werror cases, the call to strnlen (.., SIZE_MAX) is inlined.
Therefore this patch just marks the do_one_test function as noinline.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
For powerpc, strncmp is used on _dl_string_platform issued by
__tcb_parse_hwcap_and_convert_at_platform.
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.org>
Although static linker can optimize it to local call, it follows the
internal scheme to provide hidden proto and definitions.
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.org>
Although static linker can optimize it to local call, it follows the
internal scheme to provide hidden proto and definitions.
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.org>
Now that both strlen and memrchr have word vectorized implementation,
it should be faster to implement strrchr based on memrchr over the
string length instead of calling strchr on a loop.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powerpc64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
New algorithm read the lastaligned address and mask off the unwanted
bytes. The loop now read word-aligned address and check using the
has_eq macro.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powerpc64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
It also cleanups the multiple inclusion by leaving the ifunc
implementation to undef the weak_alias and libc_hidden_def.
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
New algorithm read the first aligned address and mask off the
unwanted bytes (this strategy is similar to arch-specific
implementations used on powerpc, sparc, and sh).
The loop now read word-aligned address and check using the has_eq
macro.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powerpc64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
Now that stpcpy is vectorized based on op_t, it should be better to
call it instead of strlen plus memcpy.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64-linux-gnu,
and powerpc-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
It follows the strategy:
- Align the destination on word boundary using byte operations.
- If source is also word aligned, read a word per time, check for
null (using has_zero from string-fzb.h), and write the remaining
bytes.
- If source is not word aligned, loop by aligning the source, and
merging the result of two reads. Similar to aligned case,
check for null with has_zero, and write the remaining bytes if
null is found.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64-linux-gnu,
and powerpc-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
It follows the strategy:
- Align the first input to word boundary using byte operations.
- If second input is also word aligned, read a word per time, check
for null (using has_zero), and check final words using byte
operation.
- If second input is not word aligned, loop by aligning the source,
and merge the result of two reads. Similar to aligned case, check
for null with has_zero, and check final words using byte operation.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64-linux-gnu,
and powerpc-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
It follows the strategy:
- Align the first input to word boundary using byte operations.
- If second input is also word aligned, read a word per time, check for
null (using has_zero), and check final words using byte operation.
- If second input is not word aligned, loop by aligning the source, and
merging the result of two reads. Similar to aligned case, check for
null with has_zero, and check final words using byte operation.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64-linux-gnu,
and powerpc-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
New algorithm now calls strchrnul.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powerpc64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
