| Message ID | 20240426172252.1862930-3-mic@digikod.net (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 7e4042abe2ee7c0977fd8bb049a6991b174a5e6f |
| Headers | show |
| Series | Fix Kselftest's vfork() side effects | expand |
On Fri, Apr 26, 2024 at 07:22:49PM +0200, Mickaël Salaün wrote: > According to the test environment, the mount point of the test's working > directory may be shared or not, which changes the visibility of the > nested "tmp" mount point for the test's parent process calling > umount("tmp"). > > This was spotted while running tests on different Linux distributions, > with different mount point configurations. Which distros did what? > > Cc: Günther Noack <gnoack@google.com> > Fixes: 41cca0542d7c ("selftests/harness: Fix TEST_F()'s vfork handling") > Signed-off-by: Mickaël Salaün <mic@digikod.net> > Link: https://lore.kernel.org/r/20240426172252.1862930-3-mic@digikod.net Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > --- > tools/testing/selftests/landlock/fs_test.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c > index 9a6036fbf289..46b9effd53e4 100644 > --- a/tools/testing/selftests/landlock/fs_test.c > +++ b/tools/testing/selftests/landlock/fs_test.c > @@ -293,7 +293,15 @@ static void prepare_layout(struct __test_metadata *const _metadata) > static void cleanup_layout(struct __test_metadata *const _metadata) > { > set_cap(_metadata, CAP_SYS_ADMIN); > - EXPECT_EQ(0, umount(TMP_DIR)); > + if (umount(TMP_DIR)) { > + /* > + * According to the test environment, the mount point of the > + * current directory may be shared or not, which changes the > + * visibility of the nested TMP_DIR mount point for the test's > + * parent process doing this cleanup. > + */ > + ASSERT_EQ(EINVAL, errno); > + } > clear_cap(_metadata, CAP_SYS_ADMIN); > EXPECT_EQ(0, remove_path(TMP_DIR)); > } > -- > 2.44.0 >
On Fri, Apr 26, 2024 at 12:38:17PM -0700, Kees Cook wrote: > On Fri, Apr 26, 2024 at 07:22:49PM +0200, Mickaël Salaün wrote: > > According to the test environment, the mount point of the test's working > > directory may be shared or not, which changes the visibility of the > > nested "tmp" mount point for the test's parent process calling > > umount("tmp"). > > > > This was spotted while running tests on different Linux distributions, > > with different mount point configurations. > > Which distros did what? Actually it's not related to distros, but rather container runtime (Docker) vs. non-container environment. With Docker (at least on my environment) all mount points are private, which is not the case (by default) when running the same UML environment not in a container. See https://github.com/landlock-lsm/landlock-test-tools/pull/4 I'll update the description.
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c index 9a6036fbf289..46b9effd53e4 100644 --- a/tools/testing/selftests/landlock/fs_test.c +++ b/tools/testing/selftests/landlock/fs_test.c @@ -293,7 +293,15 @@ static void prepare_layout(struct __test_metadata *const _metadata) static void cleanup_layout(struct __test_metadata *const _metadata) { set_cap(_metadata, CAP_SYS_ADMIN); - EXPECT_EQ(0, umount(TMP_DIR)); + if (umount(TMP_DIR)) { + /* + * According to the test environment, the mount point of the + * current directory may be shared or not, which changes the + * visibility of the nested TMP_DIR mount point for the test's + * parent process doing this cleanup. + */ + ASSERT_EQ(EINVAL, errno); + } clear_cap(_metadata, CAP_SYS_ADMIN); EXPECT_EQ(0, remove_path(TMP_DIR)); }
According to the test environment, the mount point of the test's working directory may be shared or not, which changes the visibility of the nested "tmp" mount point for the test's parent process calling umount("tmp"). This was spotted while running tests on different Linux distributions, with different mount point configurations. Cc: Günther Noack <gnoack@google.com> Fixes: 41cca0542d7c ("selftests/harness: Fix TEST_F()'s vfork handling") Signed-off-by: Mickaël Salaün <mic@digikod.net> Link: https://lore.kernel.org/r/20240426172252.1862930-3-mic@digikod.net --- tools/testing/selftests/landlock/fs_test.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)