On 23/09/2022 19:50, Günther Noack wrote:
On Fri, Sep 16, 2022 at 07:05:44PM +0200, Mickaël Salaün wrote:
I'd like to have tests similar to base_test.c:ruleset_fd_transfer to check
ftruncate with different kind of file descriptors and not-sandboxed
processes. That would require some code refactoring to reuse the FD passing
code.
Done. I factored out the FD sending and receiving into helper function in common.h.
Please use a dedicated patch for this refactoring.
On 08/09/2022 21:58, Günther Noack wrote:
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 87b28d14a1aa..ddc8c7e57e86 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
...
+TEST_F_FORK(layout1, truncate)
+{
+ const char *const file_rwt = file1_s1d1;
+ const char *const file_rw = file2_s1d1;
+ const char *const file_rt = file1_s1d2;
+ const char *const file_t = file2_s1d2;
+ const char *const file_none = file1_s1d3;
+ const char *const dir_t = dir_s2d1;
+ const char *const file_in_dir_t = file1_s2d1;
+ const char *const dir_w = dir_s3d1;
+ const char *const file_in_dir_w = file1_s3d1;
+ int file_rwt_fd, file_rw_fd;
These variables are unused now.
Good catch, done.
+TEST_F_FORK(layout1, ftruncate)
Great!
+{
+ /*
+ * This test opens a new file descriptor at different stages of
+ * Landlock restriction:
+ *
+ * without restriction: ftruncate works
+ * something else but truncate restricted: ftruncate works
+ * truncate restricted and permitted: ftruncate works
+ * truncate restricted and not permitted: ftruncate fails
+ *
+ * Whether this works or not is expected to depend on the time when the
+ * FD was opened, not to depend on the time when ftruncate() was
+ * called.
+ */
+ const char *const path = file1_s1d1;
+ int fd0, fd1, fd2, fd3;
You can rename them fd_layer0, fd_layer1…
Done.
+ fd0 = open(path, O_WRONLY);
+ EXPECT_EQ(0, test_ftruncate(fd0));
+
+ landlock_single_path(_metadata, path,
+ LANDLOCK_ACCESS_FS_READ_FILE |
+ LANDLOCK_ACCESS_FS_WRITE_FILE,
+ LANDLOCK_ACCESS_FS_WRITE_FILE);
I'd prefer to follow the current way to write rule layers: write all struct
rule at first and then call each enforcement steps. It is a bit more verbose
but easier to understand errors. The list of test_ftruncate checks are
straightforward to follow.
Done.
+ fd1 = open(path, O_WRONLY);
+ EXPECT_EQ(0, test_ftruncate(fd0));
+ EXPECT_EQ(0, test_ftruncate(fd1));
+
+ landlock_single_path(_metadata, path, LANDLOCK_ACCESS_FS_TRUNCATE,
+ LANDLOCK_ACCESS_FS_TRUNCATE);
+
+ fd2 = open(path, O_WRONLY);
+ EXPECT_EQ(0, test_ftruncate(fd0));
+ EXPECT_EQ(0, test_ftruncate(fd1));
+ EXPECT_EQ(0, test_ftruncate(fd2));
+
+ landlock_single_path(_metadata, path,
+ LANDLOCK_ACCESS_FS_TRUNCATE |
+ LANDLOCK_ACCESS_FS_WRITE_FILE,
+ LANDLOCK_ACCESS_FS_WRITE_FILE);
+
+ fd3 = open(path, O_WRONLY);
+ EXPECT_EQ(0, test_ftruncate(fd0));
+ EXPECT_EQ(0, test_ftruncate(fd1));
+ EXPECT_EQ(0, test_ftruncate(fd2));
+ EXPECT_EQ(EACCES, test_ftruncate(fd3));
+
+ ASSERT_EQ(0, close(fd0));
+ ASSERT_EQ(0, close(fd1));
+ ASSERT_EQ(0, close(fd2));
+ ASSERT_EQ(0, close(fd3));
+}
+
/* clang-format off */
FIXTURE(layout1_bind) {};
/* clang-format on */
