Test all filesystem blockers, including events with several records, and
record with several blockers:
- fs.execute
- fs.write_file
- fs.read_file
- fs_read_dir
- fs.remove_dir
- fs.remove_file
- fs.make_char
- fs.make_dir
- fs.make_reg
- fs.make_sock
- fs.make_fifo
- fs.make_block
- fs.make_sym
- fs.refer
- fs.truncate
- fs.ioctl_dev

Test coverage for security/landlock is 93.4% of 1407 lines according to
gcc/gcov-14.

Cc: Günther Noack <gno...@google.com>
Cc: Paul Moore <p...@paul-moore.com>
Signed-off-by: Mickaël Salaün <m...@digikod.net>
Link: https://lore.kernel.org/r/20250308184422.2159360-26-...@digikod.net
---

Changes since v5:
- New patch.
---
 tools/testing/selftests/landlock/audit.h   |  39 ++
 tools/testing/selftests/landlock/common.h  |  16 +
 tools/testing/selftests/landlock/fs_test.c | 455 +++++++++++++++++++++
 3 files changed, 510 insertions(+)

diff --git a/tools/testing/selftests/landlock/audit.h 
b/tools/testing/selftests/landlock/audit.h
index b3b3e52e8256..d84a88ff6535 100644
--- a/tools/testing/selftests/landlock/audit.h
+++ b/tools/testing/selftests/landlock/audit.h
@@ -22,6 +22,10 @@
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
 #endif
 
+#ifndef __maybe_unused
+#define __maybe_unused __attribute__((__unused__))
+#endif
+
 #define REGEX_LANDLOCK_PREFIX "^audit([0-9.:]\\+): domain=\\([0-9a-f]\\+\\)"
 
 struct audit_filter {
@@ -188,6 +192,41 @@ static int audit_set_status(int fd, __u32 key, __u32 val)
        return audit_request(fd, &msg, NULL);
 }
 
+/* Returns a pointer to the last filled character of @dst, which is `\0`.  */
+static __maybe_unused char *regex_escape(const char *const src, char *dst,
+                                        size_t dst_size)
+{
+       char *d = dst;
+
+       for (const char *s = src; *s; s++) {
+               switch (*s) {
+               case '$':
+               case '*':
+               case '.':
+               case '[':
+               case '\\':
+               case ']':
+               case '^':
+                       if (d >= dst + dst_size - 2)
+                               return (char *)-ENOMEM;
+
+                       *d++ = '\\';
+                       *d++ = *s;
+                       break;
+               default:
+                       if (d >= dst + dst_size - 1)
+                               return (char *)-ENOMEM;
+
+                       *d++ = *s;
+               }
+       }
+       if (d >= dst + dst_size - 1)
+               return (char *)-ENOMEM;
+
+       *d = '\0';
+       return d;
+}
+
 /*
  * @domain_id: The domain ID extracted from the audit message (if the first 
part
  * of @pattern is REGEX_LANDLOCK_PREFIX).  It is set to 0 if the domain ID is
diff --git a/tools/testing/selftests/landlock/common.h 
b/tools/testing/selftests/landlock/common.h
index c0a2d0b36217..ddcd8d00aeb3 100644
--- a/tools/testing/selftests/landlock/common.h
+++ b/tools/testing/selftests/landlock/common.h
@@ -207,6 +207,22 @@ enforce_ruleset(struct __test_metadata *const _metadata, 
const int ruleset_fd)
        }
 }
 
+static void __maybe_unused
+drop_access_rights(struct __test_metadata *const _metadata,
+                  const struct landlock_ruleset_attr *const ruleset_attr)
+{
+       int ruleset_fd;
+
+       ruleset_fd =
+               landlock_create_ruleset(ruleset_attr, sizeof(*ruleset_attr), 0);
+       EXPECT_LE(0, ruleset_fd)
+       {
+               TH_LOG("Failed to create a ruleset: %s", strerror(errno));
+       }
+       enforce_ruleset(_metadata, ruleset_fd);
+       EXPECT_EQ(0, close(ruleset_fd));
+}
+
 struct protocol_variant {
        int domain;
        int type;
diff --git a/tools/testing/selftests/landlock/fs_test.c 
b/tools/testing/selftests/landlock/fs_test.c
index aa6f2c1cbec7..873d38efdad7 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -41,6 +41,7 @@
 #define _ASM_GENERIC_FCNTL_H
 #include <linux/fcntl.h>
 
+#include "audit.h"
 #include "common.h"
 
 #ifndef renameat2
@@ -5554,4 +5555,458 @@ TEST_F_FORK(layout3_fs, release_inodes)
        ASSERT_EQ(EACCES, test_open(TMP_DIR, O_RDONLY));
 }
 
+static int matches_log_fs_extra(struct __test_metadata *const _metadata,
+                               int audit_fd, const char *const blockers,
+                               const char *const path, const char *const extra)
+{
+       static const char log_template[] = REGEX_LANDLOCK_PREFIX
+               " blockers=fs\\.%s path=\"%s\" dev=\"[^\"]\\+\" ino=[0-9]\\+$";
+       char *absolute_path = NULL;
+       size_t log_match_remaining = sizeof(log_template) + strlen(blockers) +
+                                    PATH_MAX * 2 +
+                                    (extra ? strlen(extra) : 0) + 1;
+       char log_match[log_match_remaining];
+       char *log_match_cursor = log_match;
+       size_t chunk_len;
+
+       chunk_len = snprintf(log_match_cursor, log_match_remaining,
+                            REGEX_LANDLOCK_PREFIX " blockers=%s path=\"",
+                            blockers);
+       if (chunk_len < 0 || chunk_len >= log_match_remaining)
+               return -E2BIG;
+
+       absolute_path = realpath(path, NULL);
+       if (!absolute_path)
+               return -errno;
+
+       log_match_remaining -= chunk_len;
+       log_match_cursor += chunk_len;
+       log_match_cursor = regex_escape(absolute_path, log_match_cursor,
+                                       log_match_remaining);
+       free(absolute_path);
+       if (log_match_cursor < 0)
+               return (long long)log_match_cursor;
+
+       log_match_remaining -= log_match_cursor - log_match;
+       chunk_len = snprintf(log_match_cursor, log_match_remaining,
+                            "\" dev=\"[^\"]\\+\" ino=[0-9]\\+%s$",
+                            extra ?: "");
+       if (chunk_len < 0 || chunk_len >= log_match_remaining)
+               return -E2BIG;
+
+       return audit_match_record(audit_fd, AUDIT_LANDLOCK_ACCESS, log_match,
+                                 NULL);
+}
+
+static int matches_log_fs(struct __test_metadata *const _metadata, int 
audit_fd,
+                         const char *const blockers, const char *const path)
+{
+       return matches_log_fs_extra(_metadata, audit_fd, blockers, path, NULL);
+}
+
+FIXTURE(audit_layout1)
+{
+       struct audit_filter audit_filter;
+       int audit_fd;
+};
+
+FIXTURE_SETUP(audit_layout1)
+{
+       prepare_layout(_metadata);
+
+       create_layout1(_metadata);
+
+       set_cap(_metadata, CAP_AUDIT_CONTROL);
+       self->audit_fd = audit_init_with_exe_filter(&self->audit_filter);
+       EXPECT_LE(0, self->audit_fd);
+       drop_caps(_metadata);
+}
+
+FIXTURE_TEARDOWN_PARENT(audit_layout1)
+{
+       remove_layout1(_metadata);
+
+       cleanup_layout(_metadata);
+
+       EXPECT_EQ(0, audit_cleanup(-1, NULL));
+}
+
+TEST_F(audit_layout1, execute)
+{
+       struct audit_records records;
+
+       copy_file(_metadata, bin_true, file1_s1d1);
+       test_execute(_metadata, 0, file1_s1d1);
+       test_check_exec(_metadata, 0, file1_s1d1);
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_EXECUTE,
+                          });
+
+       test_execute(_metadata, EACCES, file1_s1d1);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.execute",
+                                   file1_s1d1));
+
+       test_check_exec(_metadata, EACCES, file1_s1d1);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.execute",
+                                   file1_s1d1));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(0, records.domain);
+}
+
+TEST_F(audit_layout1, write_file)
+{
+       struct audit_records records;
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_WRITE_FILE,
+                          });
+
+       EXPECT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+                                   "fs\\.write_file", file1_s1d1));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, read_file)
+{
+       struct audit_records records;
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_READ_FILE,
+                          });
+
+       EXPECT_EQ(EACCES, test_open(file1_s1d1, O_RDONLY));
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.read_file",
+                                   file1_s1d1));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, read_dir)
+{
+       struct audit_records records;
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_READ_DIR,
+                          });
+
+       EXPECT_EQ(EACCES, test_open(dir_s1d1, O_DIRECTORY));
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.read_dir",
+                                   dir_s1d1));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, remove_dir)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+       EXPECT_EQ(0, unlink(file2_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_REMOVE_DIR,
+                          });
+
+       EXPECT_EQ(-1, rmdir(dir_s1d3));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+                                   "fs\\.remove_dir", dir_s1d2));
+
+       EXPECT_EQ(-1, unlinkat(AT_FDCWD, dir_s1d3, AT_REMOVEDIR));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+                                   "fs\\.remove_dir", dir_s1d2));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(0, records.domain);
+}
+
+TEST_F(audit_layout1, remove_file)
+{
+       struct audit_records records;
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_REMOVE_FILE,
+                          });
+
+       EXPECT_EQ(-1, unlink(file1_s1d3));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+                                   "fs\\.remove_file", dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_char)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_CHAR,
+                          });
+
+       EXPECT_EQ(-1, mknod(file1_s1d3, S_IFCHR | 0644, 0));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.make_char",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_dir)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_DIR,
+                          });
+
+       EXPECT_EQ(-1, mkdir(file1_s1d3, 0755));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.make_dir",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_reg)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_REG,
+                          });
+
+       EXPECT_EQ(-1, mknod(file1_s1d3, S_IFREG | 0644, 0));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.make_reg",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_sock)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_SOCK,
+                          });
+
+       EXPECT_EQ(-1, mknod(file1_s1d3, S_IFSOCK | 0644, 0));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.make_sock",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_fifo)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_FIFO,
+                          });
+
+       EXPECT_EQ(-1, mknod(file1_s1d3, S_IFIFO | 0644, 0));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.make_fifo",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_block)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_BLOCK,
+                          });
+
+       EXPECT_EQ(-1, mknod(file1_s1d3, S_IFBLK | 0644, 0));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+                                   "fs\\.make_block", dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, make_sym)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_SYM,
+                          });
+
+       EXPECT_EQ(-1, symlink("target", file1_s1d3));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.make_sym",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+// TODO: Add refer_exchange
+TEST_F(audit_layout1, refer_handled)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata, &(struct landlock_ruleset_attr){
+                                             .handled_access_fs =
+                                                     LANDLOCK_ACCESS_FS_REFER,
+                                     });
+
+       EXPECT_EQ(-1, link(file1_s1d1, file1_s1d3));
+       EXPECT_EQ(EXDEV, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.refer",
+                                   dir_s1d1));
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.refer",
+                                   dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(0, records.domain);
+}
+
+TEST_F(audit_layout1, refer_make)
+{
+       struct audit_records records;
+
+       EXPECT_EQ(0, unlink(file1_s1d3));
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_MAKE_REG |
+                                          LANDLOCK_ACCESS_FS_REFER,
+                          });
+
+       EXPECT_EQ(-1, link(file1_s1d1, file1_s1d3));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.refer",
+                                   dir_s1d1));
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+                                   "fs\\.make_reg,fs\\.refer", dir_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(0, records.domain);
+}
+
+TEST_F(audit_layout1, truncate)
+{
+       struct audit_records records;
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_TRUNCATE,
+                          });
+
+       EXPECT_EQ(-1, truncate(file1_s1d3, 0));
+       EXPECT_EQ(EACCES, errno);
+       EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd, "fs\\.truncate",
+                                   file1_s1d3));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
+TEST_F(audit_layout1, ioctl_dev)
+{
+       struct audit_records records;
+       int fd;
+
+       drop_access_rights(_metadata,
+                          &(struct landlock_ruleset_attr){
+                                  .handled_access_fs =
+                                          LANDLOCK_ACCESS_FS_IOCTL_DEV,
+                          });
+
+       fd = open("/dev/null", O_RDWR | O_CLOEXEC);
+       ASSERT_LE(0, fd);
+       EXPECT_EQ(EACCES, ioctl_error(_metadata, fd, FIONREAD));
+       EXPECT_EQ(0, matches_log_fs_extra(_metadata, self->audit_fd,
+                                         "fs\\.ioctl_dev", "/dev/null",
+                                         " ioctlcmd=0x541b"));
+
+       audit_count_records(self->audit_fd, &records);
+       EXPECT_EQ(0, records.access);
+       EXPECT_EQ(1, records.domain);
+}
+
 TEST_HARNESS_MAIN
-- 
2.48.1


Reply via email to