If /proc/self/uid_map doesn't exist, mount test case exits
wthout any warning. Fix it to print a warning that the test
is skipped because /proc/self/uid_map doesn't exist.
Signed-off-by: NZhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Use the CC variable instead of hard coding gcc. Also clean up the compiler
options by creating a CFLAGS variable.
Signed-off-by: NTyler Baker <tyler.baker@linaro.org>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

This adds make install support to selftests. The basic usage is:

$ cd tools/testing/selftests
$ make install

That installs into tools/testing/selftests/install, which can then be
copied where ever necessary.

The install destination is also configurable using eg:

$ INSTALL_PATH=/mnt/selftests make install

The implementation uses two targets in the child makefiles. The first
"install" is expected to install all files into $(INSTALL_PATH).

The second, "emit_tests", is expected to emit the test instructions (ie.
bash script) on stdout. Separating this from install means the child
makefiles need no knowledge of the location of the test script.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

This adds a Make include file which most selftests can then include to
get the run_tests logic.

On its own this has the advantage of some reduction in repetition, and
also means the pass/fail message is defined in fewer places.

However the key advantage is it will allow us to implement install very
simply in a subsequent patch.

The default implementation just executes each program in $(TEST_PROGS).

We use a variable to hold the default implementation of $(RUN_TESTS)
because that gives us a clean way to override it if necessary, ie. using
override. The mount, memory-hotplug and mqueue tests use that to provide
a different implementation.

Tests are not run via /bin/bash, so if they are scripts they must be
executable, we add a+x to several.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Kenton Varda <kenton@sandstorm.io> discovered that by remounting a
read-only bind mount read-only in a user namespace the
MNT_LOCK_READONLY bit would be cleared, allowing an unprivileged user
to the remount a read-only mount read-write.

Upon review of the code in remount it was discovered that the code allowed
nosuid, noexec, and nodev to be cleared.  It was also discovered that
the code was allowing the per mount atime flags to be changed.

The first naive patch to fix these issues contained the flaw that using
default atime settings when remounting a filesystem could be disallowed.

To avoid this problems in the future add tests to ensure unprivileged
remounts are succeeding and failing at the appropriate times.

Cc: stable@vger.kernel.org
Acked-by: NSerge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>