This executable is missing from the corresponding gitignore file.
Add unshare_test to the core gitignore list.

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Pull kselftest update from Shuah Khan:

 - test coverage for dup_fd() failure handling in unshare_fd()

 - new selftest for the acct() syscall

 - basic uprobe testcase

 - several small fixes and cleanups to existing tests

 - user and strscpy removal as they became kunit tests

 - fixes to build failures and warnings

* tag 'linux_kselftest-next-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (21 commits)
  selftests: kselftest: Use strerror() on nolibc
  selftests/timers: Remove unused NSEC_PER_SEC macro
  selftests:resctrl: Fix build failure on archs without __cpuid_count()
  selftests/ftrace: Fix eventfs ownership testcase to find mount point
  selftests: filesystems: fix warn_unused_result build warnings
  selftests:core: test coverage for dup_fd() failure handling in unshare_fd()
  selftests/ftrace: Fix test to handle both old and new kernels
  kselftest: timers: Fix const correctness
  selftests/ftrace: Add required dependency for kprobe tests
  selftests: rust: config: disable GCC_PLUGINS
  selftests: rust: config: add trailing newline
  tracing/selftests: Run the ownership test twice
  selftests/uprobes: Add a basic uprobe testcase
  selftests: harness: rename __constructor_order for clarification
  selftests: harness: remove unneeded __constructor_order_last()
  selftest: acct: Add selftest for the acct() syscall
  selftests: lib: remove strscpy test
  selftests: user: remove user suite
  kselftest: cpufreq: Add RTC wakeup alarm
  selftests/exec: Fix grammar in an error message.
  ...

At some point there'd been a dumb braino during the dup_fd()
calling conventions change; caught by smatch and immediately fixed.
The trouble is, there had been no test coverage for the dup_fd() failure
handling - neither in kselftests nor in LTP.  Fortunately, it can be
triggered on stock kernel - ENOMEM would require fault injection, but
EMFILE can be had with sysctl alone (fs.nr_open).

Add a test for dup_fd() failure.
Fixed up commit log and short log - Shuah Khan

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Add simple selftests for fcntl(fd, F_CREATED_QUERY, 0).

Link: https://lore.kernel.org/r/20240724-work-fcntl-v1-2-e8153a2f1991@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

copy_fd_bitmaps(new, old, count) is expected to copy the first
count/BITS_PER_LONG bits from old->full_fds_bits[] and fill
the rest with zeroes.  What it does is copying enough words
(BITS_TO_LONGS(count/BITS_PER_LONG)), then memsets the rest.
That works fine, *if* all bits past the cutoff point are
clear.  Otherwise we are risking garbage from the last word
we'd copied.

For most of the callers that is true - expand_fdtable() has
count equal to old->max_fds, so there's no open descriptors
past count, let alone fully occupied words in ->open_fds[],
which is what bits in ->full_fds_bits[] correspond to.

The other caller (dup_fd()) passes sane_fdtable_size(old_fdt, max_fds),
which is the smallest multiple of BITS_PER_LONG that covers all
opened descriptors below max_fds.  In the common case (copying on
fork()) max_fds is ~0U, so all opened descriptors will be below
it and we are fine, by the same reasons why the call in expand_fdtable()
is safe.

Unfortunately, there is a case where max_fds is less than that
and where we might, indeed, end up with junk in ->full_fds_bits[] -
close_range(from, to, CLOSE_RANGE_UNSHARE) with
	* descriptor table being currently shared
	* 'to' being above the current capacity of descriptor table
	* 'from' being just under some chunk of opened descriptors.
In that case we end up with observably wrong behaviour - e.g. spawn
a child with CLONE_FILES, get all descriptors in range 0..127 open,
then close_range(64, ~0U, CLOSE_RANGE_UNSHARE) and watch dup(0) ending
up with descriptor #128, despite #64 being observably not open.

The minimally invasive fix would be to deal with that in dup_fd().
If this proves to add measurable overhead, we can go that way, but
let's try to fix copy_fd_bitmaps() first.

* new helper: bitmap_copy_and_expand(to, from, bits_to_copy, size).
* make copy_fd_bitmaps() take the bitmap size in words, rather than
bits; it's 'count' argument is always a multiple of BITS_PER_LONG,
so we are not losing any information, and that way we can use the
same helper for all three bitmaps - compiler will see that count
is a multiple of BITS_PER_LONG for the large ones, so it'll generate
plain memcpy()+memset().

Reproducer added to tools/testing/selftests/core/close_range_test.c

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Add simple selftests for the new F_DUPFD_QUERY fcntl().

Signed-off-by: Christian Brauner <brauner@kernel.org>

Correct header file is needed for getting CLOSE_RANGE_* macros. 
Previously it was tested with newer glibc which didn't show the need to
include the header which was a mistake.

Link: https://lkml.kernel.org/r/20231024155137.219700-1-usama.anjum@collabora.com
Fixes: ec54424923cf ("selftests: core: remove duplicate defines")
Reported-by: Aishwarya TCV <aishwarya.tcv@arm.com>
Link: https://lore.kernel.org/all/7161219e-0223-d699-d6f3-81abd9abf13b@arm.com
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Remove duplicate defines which are already defined in kernel headers and
re-definition isn't required.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Use $(KHDR_INCLUDES) as lookup path for kernel headers. This prevents
building against kernel headers from the build environment in scenarios
where kernel headers are installed into a specific output directory
(O=...).

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: linux-kselftest@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <stable@vger.kernel.org> # 5.18+
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

ARRAY_SIZE is defined in several selftests. Remove definitions from
individual test files and include header file for the define instead.
ARRAY_SIZE define is added in a separate patch to prepare for this
change.

Remove ARRAY_SIZE from close_range_test.c and pickup the one defined
in kselftest.h.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>