Commit Graph

4 Commits

Author SHA1 Message Date
John Hubbard
ed3994ac84 selftests/fchmodat2: fix clang build failure due to -static-libasan
gcc requires -static-libasan in order to ensure that Address Sanitizer's
library is the first one loaded. However, this leads to build failures
on clang, when building via:

    make LLVM=1 -C tools/testing/selftests

However, clang already does the right thing by default: it statically
links the Address Sanitizer if -fsanitize is specified. Therefore,
simply omit -static-libasan for clang builds. And leave behind a
comment, because the whole reason for static linking might not be
obvious.

Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-11 15:05:05 -06:00
Ryan Roberts
c652df8a4a selftests: link libasan statically for tests with -fsanitize=address
When dynamically linking, Address Sanitizer requires its library to be the
first one to be loaded; this is apparently to ensure that every call to
malloc is intercepted.  If using LD_PRELOAD, those listed libraries will
be loaded before the libraries listed in the program's ELF and will
therefore violate this requirement, leading to the below failure and
output from ASan.

commit 58e2847ad2 ("selftests: line buffer test program's stdout")
modified the kselftest runner to force line buffering by forcing the test
programs to run through `stdbuf`.  It turns out that stdbuf implements
line buffering by injecting a library via LD_PRELOAD.  Therefore selftests
that use ASan started failing.

Fix this by statically linking libasan in the affected test programs,
using the `-static-libasan` option.  Note this is already the default for
Clang, but not got GCC.

Test output sample for failing case:

  TAP version 13
  1..3
  # timeout set to 300
  # selftests: openat2: openat2_test
  # ==4052==ASan runtime does not come first in initial library list;
  you should either link runtime to your application or manually preload
  it with LD_PRELOAD.
  not ok 1 selftests: openat2: openat2_test # exit=1
  # timeout set to 300
  # selftests: openat2: resolve_test
  # ==4070==ASan runtime does not come first in initial library list;
  you should either link runtime to your application or manually preload
  it with LD_PRELOAD.
  not ok 2 selftests: openat2: resolve_test # exit=1

Link: https://lkml.kernel.org/r/20230912135048.1755771-1-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Fixes: 58e2847ad2 ("selftests: line buffer test program's stdout")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202309121342.97e2f008-oliver.sang@intel.com
Cc: David Hildenbrand <david@redhat.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Rix <trix@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-19 13:21:32 -07:00
Muhammad Usama Anjum
7121437953
selftests: fchmodat2: remove duplicate unneeded defines
These duplicate defines should automatically be picked up from kernel
headers. Use KHDR_INCLUDES to add kernel header files.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Message-Id: <20230805073809.1753462-4-usama.anjum@collabora.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-08-05 12:40:44 +02:00
Alexey Gladkov
4859c257d2
selftests: Add fchmodat2 selftest
The test marks as skipped if a syscall with the AT_SYMLINK_NOFOLLOW flag
fails. This is because not all filesystems support changing the mode
bits of symlinks properly. These filesystems return an error but change
the mode bits:

newfstatat(4, "regfile", {st_mode=S_IFREG|0640, st_size=0, ...}, AT_SYMLINK_NOFOLLOW) = 0
newfstatat(4, "symlink", {st_mode=S_IFLNK|0777, st_size=7, ...}, AT_SYMLINK_NOFOLLOW) = 0
syscall_0x1c3(0x4, 0x55fa1f244396, 0x180, 0x100, 0x55fa1f24438e, 0x34) = -1 EOPNOTSUPP (Operation not supported)
newfstatat(4, "regfile", {st_mode=S_IFREG|0640, st_size=0, ...}, AT_SYMLINK_NOFOLLOW) = 0

This happens with btrfs and xfs:

 $ tools/testing/selftests/fchmodat2/fchmodat2_test
 TAP version 13
 1..1
 ok 1 # SKIP fchmodat2(symlink)
 # Totals: pass:0 fail:0 xfail:0 xpass:0 skip:1 error:0

 $ stat /tmp/ksft-fchmodat2.*/symlink
   File: /tmp/ksft-fchmodat2.3NCqlE/symlink -> regfile
   Size: 7               Blocks: 0          IO Block: 4096   symbolic link
 Device: 7,0     Inode: 133         Links: 1
 Access: (0600/lrw-------)  Uid: (    0/    root)   Gid: (    0/    root)

Signed-off-by: Alexey Gladkov <legion@kernel.org>
Message-Id: <4532a04a870ff589ba62ceeacf76f0bd81b9ba01.1689092120.git.legion@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-27 12:25:35 +02:00