glibc/io
Siddhesh Poyarekar 0e6ebf06e4 Make sure that the fortified function conditionals are constant
In _FORTIFY_SOURCE=3, the size expression may be non-constant,
resulting in branches in the inline functions remaining intact and
causing a tiny overhead.  Clang (and in future, gcc) make sure that
the -1 case is always safe, i.e. any comparison of the generated
expression with (size_t)-1 is always false so that bit is taken care
of.  The rest is avoidable since we want the _chk variant whenever we
have a size expression and it's not -1.

Rework the conditionals in a uniform way to clearly indicate two
conditions at compile time:

- Either the size is unknown (-1) or we know at compile time that the
  operation length is less than the object size.  We can call the
  original function in this case.  It could be that either the length,
  object size or both are non-constant, but the compiler, through
  range analysis, is able to fold the *comparison* to a constant.

- The size and length are known and the compiler can see at compile
  time that operation length > object size.  This is valid grounds for
  a warning at compile time, followed by emitting the _chk variant.

For everything else, emit the _chk variant.

This simplifies most of the fortified function implementations and at
the same time, ensures that only one call from _chk or the regular
function is emitted.

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit a643f60c53)
2022-03-11 20:36:24 +05:30
..
bits Make sure that the fortified function conditionals are constant 2022-03-11 20:36:24 +05:30
sys Don't add access size hints to fortifiable functions 2022-03-11 20:36:24 +05:30
access.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
bug-ftw1.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
bug-ftw2.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
bug-ftw3.c Update. 2002-02-07 17:54:45 +00:00
bug-ftw4.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
bug-ftw5.c [BZ #4076] 2007-02-21 09:36:46 +00:00
chdir.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
chmod.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
chown.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
close.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
closefrom.c io: Add closefrom [BZ #10353] 2021-07-08 14:08:14 -03:00
copy_file_range.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
creat64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
creat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
dup2.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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dup.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
euidaccess.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
faccessat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fchdir.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fchmod.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fchmodat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fchown.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fchownat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fcntl64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fcntl.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fcntl.h Linux: Fix fcntl, ioctl, prctl redirects for _TIME_BITS=64 (bug 28182) 2021-08-06 16:42:40 +02:00
file_change_detection.c hurd: Fix build after 52a5fe70a2 2021-06-23 14:14:48 -03:00
flock.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fstat64.c io: Return EBAFD for negative file descriptor on fstat (BZ #27559) 2021-03-11 10:51:55 -03:00
fstat.c io: Return EBAFD for negative file descriptor on fstat (BZ #27559) 2021-03-11 10:51:55 -03:00
fstatat64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fstatat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fstatfs64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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fstatvfs64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fstatvfs.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fts64-time64.c io: Add fts64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
fts64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fts.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
fts.h io: Add fts64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
ftw64-time64.c io: Add ftw64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
ftw64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
ftw.c io: Add ftw64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
ftw.h io: Add ftw64 with 64-bit time_t support 2021-06-15 10:42:11 -03:00
ftwtest-sh io: Use temporary directory and file for ftwtest-sh 2021-04-15 09:39:53 -03:00
ftwtest-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
ftwtest.c Update. 2003-11-07 23:00:00 +00:00
futimens.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
getcwd.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
getdirname.c Use 64 bit time_t stat internally 2021-06-22 12:09:52 -03:00
getwd.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
isatty.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
lchmod.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
lchown.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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lseek64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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lstat64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
lstat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
Makefile io: Add time64 alias for fcntl 2021-07-21 11:58:16 +02:00
mkdir.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
mkdirat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
mkfifo.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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mknod.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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poll.h
posix_fadvise64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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test-lfs.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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test-utime.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-closefrom.c Use support_open_dev_null_range io/tst-closefrom, misc/tst-close_range, and posix/tst-spawn5 (BZ #28260) 2021-09-21 22:26:26 +12:00
tst-copy_file_range.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-faccessat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-fchmodat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-fchownat.c Revert "hurd: Fix building io/tst-fchownat.c" 2018-01-28 19:13:20 +01:00
tst-fcntl-time64.c io: Add time64 alias for fcntl 2021-07-21 11:58:16 +02:00
tst-fcntl.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-file_change_detection.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-fstatat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-fts-lfs.c Add LFS support for fts functions (bug 11460) 2015-11-06 11:24:16 +01:00
tst-fts-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-fts.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-ftw-bz26353.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-ftw-lnk.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-futimens-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-futimens.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-futimes-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-futimes.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-futimesat-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-futimesat.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-getcwd-abspath.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-getcwd.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-lchmod.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-linkat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-lockf.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-lutimes-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-lutimes.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-mkdirat.c Assume that _DIRENT_HAVE_D_TYPE is always defined. 2017-10-30 15:48:33 +01:00
tst-mkfifoat.c Assume that _DIRENT_HAVE_D_TYPE is always defined. 2017-10-30 15:48:33 +01:00
tst-mknodat.c Assume that _DIRENT_HAVE_D_TYPE is always defined. 2017-10-30 15:48:33 +01:00
tst-open-tmpfile.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-openat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-posix_fallocate64.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-posix_fallocate-common.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-posix_fallocate.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-readlinkat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-renameat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-stat-lfs.c io: Return EBAFD for negative file descriptor on fstat (BZ #27559) 2021-03-11 10:51:55 -03:00
tst-stat-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-stat.c io: Add fsync call in tst-stat 2022-03-11 11:13:33 +01:00
tst-statvfs.c Update. 2003-10-27 04:05:04 +00:00
tst-statx.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
tst-symlinkat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-ttyname_r.c * nis/nis_subr.c (nis_getnames): Revert last change. 2006-12-05 21:28:15 +00:00
tst-unlinkat.c Add missing header files throughout the testsuite. 2017-02-16 17:33:18 -05:00
tst-utime-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-utime.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-utimensat-skeleton.c linux: Add lutimes test 2021-04-15 09:39:49 -03:00
tst-utimensat-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-utimensat.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-utimes-time64.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
tst-utimes.c y2038: Add test coverage 2021-06-15 10:42:11 -03:00
ttyname_r.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
ttyname.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
umask.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
unlink.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
unlinkat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
utime.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
utime.h y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
utimensat.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
Versions io: Add closefrom [BZ #10353] 2021-07-08 14:08:14 -03:00
write.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00