From 58dfcc57f25f99fe541d67ef15b6c66dfc40912b Mon Sep 17 00:00:00 2001 From: Yu Watanabe Date: Thu, 16 Mar 2023 04:50:08 +0900 Subject: [PATCH] test: add a testcase that dir_fd_is_root() is not confused by bind mount See the comment in dir_fd_is_root() and https://github.com/systemd/systemd/pull/26820#issuecomment-1469554966. --- src/test/test-fd-util.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/src/test/test-fd-util.c b/src/test/test-fd-util.c index c5f32aa6792..1f14f0b6cb4 100644 --- a/src/test/test-fd-util.c +++ b/src/test/test-fd-util.c @@ -2,6 +2,7 @@ #include #include +#include #include #include "alloc-util.h" @@ -11,11 +12,14 @@ #include "macro.h" #include "memory-util.h" #include "missing_syscall.h" +#include "mkdir.h" #include "mount-util.h" +#include "namespace-util.h" #include "path-util.h" #include "process-util.h" #include "random-util.h" #include "rlimit-util.h" +#include "rm-rf.h" #include "seccomp-util.h" #include "serialize.h" #include "string-util.h" @@ -571,6 +575,7 @@ TEST(take_fd) { TEST(dir_fd_is_root) { _cleanup_close_ int fd = -EBADF; + int r; assert_se((fd = open("/", O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0); assert_se(dir_fd_is_root(fd) > 0); @@ -579,6 +584,34 @@ TEST(dir_fd_is_root) { assert_se((fd = open("/usr", O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0); assert_se(dir_fd_is_root(fd) == 0); + + r = detach_mount_namespace(); + if (r < 0) + return (void) log_tests_skipped_errno(r, "Failed to detach mount namespace"); + + _cleanup_(rm_rf_physical_and_freep) char *tmp = NULL; + _cleanup_free_ char *x = NULL, *y = NULL; + + assert_se(mkdtemp_malloc("/tmp/test-mkdir-XXXXXX", &tmp) >= 0); + assert_se(x = path_join(tmp, "x")); + assert_se(y = path_join(tmp, "x/y")); + assert_se(mkdir_p(y, 0755) >= 0); + assert_se(mount_nofollow_verbose(LOG_DEBUG, x, y, NULL, MS_BIND, NULL) >= 0); + + fd = safe_close(fd); + + assert_se((fd = open(tmp, O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0); + assert_se(dir_fd_is_root(fd) == 0); + + fd = safe_close(fd); + + assert_se((fd = open(x, O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0); + assert_se(dir_fd_is_root(fd) == 0); + + fd = safe_close(fd); + + assert_se((fd = open(y, O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0); + assert_se(dir_fd_is_root(fd) == 0); } DEFINE_TEST_MAIN(LOG_DEBUG); -- 2.47.3