The following APIs are tested with simple scenarios. 1. chmod/fchmod/fchmodat; 2. chmod/fchmod/lchown/fchownat;
The key point is that set these access rights on a directory but only for its content, not the directory itself. this scenario is covered.
Signed-off-by: Xiu Jianfeng xiujianfeng@huawei.com --- tools/testing/selftests/landlock/fs_test.c | 261 +++++++++++++++++++++ 1 file changed, 261 insertions(+)
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c index f513cd8d9d51..982cb824967c 100644 --- a/tools/testing/selftests/landlock/fs_test.c +++ b/tools/testing/selftests/landlock/fs_test.c @@ -3272,6 +3272,267 @@ TEST_F_FORK(layout1, truncate) EXPECT_EQ(0, test_creat(file_in_dir_w)); }
+/* Invokes chmod(2) and returns its errno or 0. */ +static int test_chmod(const char *const path, mode_t mode) +{ + if (chmod(path, mode) < 0) + return errno; + return 0; +} + +/* Invokes fchmod(2) and returns its errno or 0. */ +static int test_fchmod(int fd, mode_t mode) +{ + if (fchmod(fd, mode) < 0) + return errno; + return 0; +} + +/* Invokes fchmodat(2) and returns its errno or 0. */ +static int test_fchmodat(int dirfd, const char *path, mode_t mode, int flags) +{ + if (fchmodat(dirfd, path, mode, flags) < 0) + return errno; + return 0; +} + +/* Invokes chown(2) and returns its errno or 0. */ +static int test_chown(const char *path, uid_t uid, gid_t gid) +{ + if (chown(path, uid, gid) < 0) + return errno; + return 0; +} + +/* Invokes fchown(2) and returns its errno or 0. */ +static int test_fchown(int fd, uid_t uid, gid_t gid) +{ + if (fchown(fd, uid, gid) < 0) + return errno; + return 0; +} + +/* Invokes lchown(2) and returns its errno or 0. */ +static int test_lchown(const char *path, uid_t uid, gid_t gid) +{ + if (lchown(path, uid, gid) < 0) + return errno; + return 0; +} + +/* Invokes fchownat(2) and returns its errno or 0. */ +static int test_fchownat(int dirfd, const char *path, + uid_t uid, gid_t gid, int flags) +{ + if (fchownat(dirfd, path, uid, gid, flags) < 0) + return errno; + return 0; +} + +TEST_F_FORK(layout1, unhandled_chmod) +{ + int ruleset_fd, file1_fd; + const char *file1 = file1_s1d1; + const char *file2 = file2_s1d1; + const char *dir1 = dir_s1d1; + const struct rule rules[] = { + { + .path = file1, + .access = LANDLOCK_ACCESS_FS_WRITE_FILE, + }, + { + .path = file2, + .access = LANDLOCK_ACCESS_FS_READ_FILE | + LANDLOCK_ACCESS_FS_WRITE_FILE, + }, + { + .path = dir1, + .access = ACCESS_RW, + }, + {}, + }; + + ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules); + ASSERT_LE(0, ruleset_fd); + file1_fd = open(file1, O_WRONLY | O_CLOEXEC); + ASSERT_LE(0, file1_fd); + + enforce_ruleset(_metadata, ruleset_fd); + ASSERT_EQ(0, close(ruleset_fd)); + + EXPECT_EQ(0, test_chmod(file1, 0400)); + EXPECT_EQ(0, test_fchmod(file1_fd, 0400)); + EXPECT_EQ(0, test_fchmodat(AT_FDCWD, file1, 0400, 0)); + EXPECT_EQ(0, test_chmod(file2, 0400)); + EXPECT_EQ(0, test_chmod(dir1, 0700)); + ASSERT_EQ(0, close(file1_fd)); +} + +TEST_F_FORK(layout1, chmod) +{ + int ruleset_fd, file1_fd; + const char *file1 = file1_s1d1; + const char *file2 = file2_s1d1; + const char *file3 = file1_s2d1; + const char *dir1 = dir_s1d1; + const char *dir2 = dir_s2d1; + const struct rule rules[] = { + { + .path = file1, + .access = LANDLOCK_ACCESS_FS_WRITE_FILE | + LANDLOCK_ACCESS_FS_CHMOD, + }, + { + .path = file2, + .access = LANDLOCK_ACCESS_FS_READ_FILE | + LANDLOCK_ACCESS_FS_WRITE_FILE, + }, + { + .path = dir1, + .access = ACCESS_RW, + }, + { + .path = dir2, + .access = ACCESS_RW | LANDLOCK_ACCESS_FS_CHMOD, + }, + {}, + }; + + ruleset_fd = create_ruleset(_metadata, ACCESS_RW | LANDLOCK_ACCESS_FS_CHMOD, rules); + ASSERT_LE(0, ruleset_fd); + file1_fd = open(file1, O_WRONLY | O_CLOEXEC); + ASSERT_LE(0, file1_fd); + + enforce_ruleset(_metadata, ruleset_fd); + ASSERT_EQ(0, close(ruleset_fd)); + + EXPECT_EQ(0, test_chmod(file1, 0400)); + EXPECT_EQ(0, test_fchmod(file1_fd, 0400)); + EXPECT_EQ(0, test_fchmodat(AT_FDCWD, file1, 0400, 0)); + EXPECT_EQ(EACCES, test_chmod(file2, 0400)); + EXPECT_EQ(EACCES, test_chmod(dir1, 0700)); + /* set CHMOD right on dir will only affect its context not dir itself*/ + EXPECT_EQ(0, test_chmod(file3, 0400)); + EXPECT_EQ(0, test_fchmodat(AT_FDCWD, file3, 0400, 0)); + EXPECT_EQ(EACCES, test_chmod(dir2, 0700)); + EXPECT_EQ(EACCES, test_fchmodat(AT_FDCWD, dir2, 0700, 0)); + ASSERT_EQ(0, close(file1_fd)); +} + +TEST_F_FORK(layout1, unhandled_chown) +{ + int ruleset_fd, file1_fd; + const char *file1 = file1_s1d1; + const char *file2 = file2_s1d1; + const char *dir1 = dir_s1d1; + const struct rule rules[] = { + { + .path = file1, + .access = LANDLOCK_ACCESS_FS_WRITE_FILE, + }, + { + .path = file2, + .access = LANDLOCK_ACCESS_FS_READ_FILE | + LANDLOCK_ACCESS_FS_WRITE_FILE, + }, + { + .path = dir1, + .access = ACCESS_RW, + }, + {}, + }; + struct stat st; + uid_t uid; + gid_t gid; + + ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules); + ASSERT_LE(0, ruleset_fd); + file1_fd = open(file1, O_WRONLY | O_CLOEXEC); + ASSERT_LE(0, file1_fd); + /* + * there is no CAP_CHOWN when the testcases framework setup, + * and we cannot assume the testcases are run as root, to make + * sure {f}chown syscall won't fail, get the original uid/gid and + * use them in test_{f}chown. + */ + ASSERT_EQ(0, stat(dir1, &st)); + uid = st.st_uid; + gid = st.st_gid; + + enforce_ruleset(_metadata, ruleset_fd); + ASSERT_EQ(0, close(ruleset_fd)); + + EXPECT_EQ(0, test_chown(file1, uid, gid)); + EXPECT_EQ(0, test_fchown(file1_fd, uid, gid)); + EXPECT_EQ(0, test_lchown(file1, uid, gid)); + EXPECT_EQ(0, test_fchownat(AT_FDCWD, file1, uid, gid, 0)); + EXPECT_EQ(0, test_chown(file2, uid, gid)); + EXPECT_EQ(0, test_chown(dir1, uid, gid)); + ASSERT_EQ(0, close(file1_fd)); +} + +TEST_F_FORK(layout1, chown) +{ + int ruleset_fd, file1_fd; + const char *file1 = file1_s1d1; + const char *file2 = file2_s1d1; + const char *file3 = file1_s2d1; + const char *dir1 = dir_s1d1; + const char *dir2 = dir_s2d1; + const struct rule rules[] = { + { + .path = file1, + .access = LANDLOCK_ACCESS_FS_WRITE_FILE | + LANDLOCK_ACCESS_FS_CHGRP, + }, + { + .path = file2, + .access = LANDLOCK_ACCESS_FS_READ_FILE | + LANDLOCK_ACCESS_FS_WRITE_FILE, + }, + { + .path = dir1, + .access = ACCESS_RW, + }, + { + .path = dir2, + .access = ACCESS_RW | LANDLOCK_ACCESS_FS_CHGRP, + }, + {}, + }; + struct stat st; + uid_t uid; + gid_t gid; + + ruleset_fd = create_ruleset(_metadata, ACCESS_RW | LANDLOCK_ACCESS_FS_CHGRP, rules); + ASSERT_LE(0, ruleset_fd); + file1_fd = open(file1, O_WRONLY | O_CLOEXEC); + ASSERT_LE(0, file1_fd); + /* + * there is no CAP_CHOWN when the testcases framework setup, + * and we cannot assume the testcases are run as root, to make + * sure {f}chown syscall won't fail, get the original uid/gid and + * use them in test_{f}chown. + */ + ASSERT_EQ(0, stat(dir1, &st)); + uid = st.st_uid; + gid = st.st_gid; + + enforce_ruleset(_metadata, ruleset_fd); + ASSERT_EQ(0, close(ruleset_fd)); + + EXPECT_EQ(0, test_chown(file1, uid, gid)); + EXPECT_EQ(0, test_fchown(file1_fd, uid, gid)); + EXPECT_EQ(0, test_lchown(file1, uid, gid)); + EXPECT_EQ(0, test_fchownat(AT_FDCWD, file1, uid, gid, 0)); + EXPECT_EQ(EACCES, test_chown(file2, uid, gid)); + EXPECT_EQ(EACCES, test_chown(dir1, uid, gid)); + /* set CHOWN right on dir will only affect its context not dir itself*/ + EXPECT_EQ(0, test_chown(file3, uid, gid)); + EXPECT_EQ(EACCES, test_chown(dir2, uid, gid)); + ASSERT_EQ(0, close(file1_fd)); +} + /* clang-format off */ FIXTURE(layout1_bind) {}; /* clang-format on */