From: Christian Kellner <christ...@kellner.me>
Add tests that check that if pid namespaces are configured the fdinfo
file of a pidfd contains an NSpid: entry containing the process id
in the current and additionally all nested namespaces.
Signed-off-by: Christian Kellner <christ...@kellner.me>
---
tools/testing/selftests/pidfd/Makefile | 2 +-
tools/testing/selftests/pidfd/pidfd.h | 12 +++
.../selftests/pidfd/pidfd_fdinfo_test.c | 98 +++++++++++++++++++
tools/testing/selftests/pidfd/pidfd_test.c | 12 ---
4 files changed, 111 insertions(+), 13 deletions(-)
create mode 100644 tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
diff --git a/tools/testing/selftests/pidfd/Makefile
b/tools/testing/selftests/pidfd/Makefile
index 7550f08822a3..43db1b98e845 100644
--- a/tools/testing/selftests/pidfd/Makefile
+++ b/tools/testing/selftests/pidfd/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
CFLAGS += -g -I../../../../usr/include/ -pthread
-TEST_GEN_PROGS := pidfd_test pidfd_open_test pidfd_poll_test pidfd_wait
+TEST_GEN_PROGS := pidfd_test pidfd_fdinfo_test pidfd_open_test pidfd_poll_test
pidfd_wait
include ../lib.mk
diff --git a/tools/testing/selftests/pidfd/pidfd.h
b/tools/testing/selftests/pidfd/pidfd.h
index c6bc68329f4b..2946d788645b 100644
--- a/tools/testing/selftests/pidfd/pidfd.h
+++ b/tools/testing/selftests/pidfd/pidfd.h
@@ -84,4 +84,16 @@ static inline int sys_pidfd_send_signal(int pidfd, int sig,
siginfo_t *info,
return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
}
+static pid_t pidfd_clone(int flags, int *pidfd, int (*fn)(void *))
+{
+ size_t stack_size = 1024;
+ char *stack[1024] = { 0 };
+
+#ifdef __ia64__
+ return __clone2(fn, stack, stack_size, flags | SIGCHLD, NULL, pidfd);
+#else
+ return clone(fn, stack + stack_size, flags | SIGCHLD, NULL, pidfd);
+#endif
+}
+
#endif /* __PIDFD_H */
diff --git a/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
b/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
new file mode 100644
index 000000000000..fbae502ad8ad
--- /dev/null
+++ b/tools/testing/selftests/pidfd/pidfd_fdinfo_test.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/types.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syscall.h>
+#include <sys/wait.h>
+
+#include "pidfd.h"
+#include "../kselftest.h"
+
+static int child_fdinfo_nspid_test(void *args)
+{
+ ksft_print_msg("Child: pid %d\n", getpid());
+ return 0;
+}
+
+static int compare_fdinfo_nspid(int pidfd, char *expect, size_t len)
+{
+ char path[512];
+ FILE *f;
+ size_t n = 0;
+ ssize_t k;
+ char *line = NULL;
+ int r = -1;
+
+ snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", pidfd);
+
+ f = fopen(path, "re");
+ if (!f)
+ return -1;
+
+ while ((k = getline(&line, &n, f)) != -1) {
+ if (strncmp(line, "NSpid:", 6))
+ continue;
+
+ line[k - 1] = '\0';
+ ksft_print_msg("Child: fdinfo NSpid line: '%s'.\n", line);
+ r = strncmp(line + 6, expect, len);
+ break;
+ }
+
+ free(line);
+ fclose(f);
+
+ return r;
+}
+
+static void test_pidfd_fdinfo_nspid(void)
+{
+ char expect[512];
+ int pid, pidfd = 0;
+ int n, r;
+ const char *test_name = "pidfd check for NSpid information in fdinfo";
+
+ pid = pidfd_clone(CLONE_PIDFD | CLONE_NEWPID | CLONE_NEWUSER, &pidfd,
+ child_fdinfo_nspid_test);
+ if (pid < 0)
+ ksft_exit_fail_msg(
+ "%s test: pidfd_clone failed (ret %d, errno %d)\n",
+ test_name, pid, errno);
+
+ ksft_print_msg("Parent: child-pid: %d\n", pid);
+
+ /* The child will have pid 1 in the new pid namespace,
+ * so the line must be 'NSPid:\t<pid>\t1'
+ */
+ n = snprintf(expect, sizeof(expect), "\t%d\t%d", pid, 1);
+ r = compare_fdinfo_nspid(pidfd, expect, n);
+
+ (void)close(pidfd);
+
+ if (wait_for_pid(pid))
+ ksft_exit_fail_msg(
+ "%s test: waitpid failed (ret %d, errno %d)\n",
+ test_name, r, errno);
+
+ if (r != 0)
+ ksft_exit_fail_msg("%s test: Failed\n", test_name);
+ else
+ ksft_test_result_pass("%s test: Passed\n", test_name);
+}
+
+int main(int argc, char **argv)
+{
+ ksft_print_header();
+ ksft_set_plan(1);
+
+ test_pidfd_fdinfo_nspid();
+
+ return ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/pidfd/pidfd_test.c
b/tools/testing/selftests/pidfd/pidfd_test.c
index 7aff2d3b42c0..9cf0b6b3e389 100644
--- a/tools/testing/selftests/pidfd/pidfd_test.c
+++ b/tools/testing/selftests/pidfd/pidfd_test.c
@@ -27,18 +27,6 @@
#define MAX_EVENTS 5
-static pid_t pidfd_clone(int flags, int *pidfd, int (*fn)(void *))
-{
- size_t stack_size = 1024;
- char *stack[1024] = { 0 };
-
-#ifdef __ia64__
- return __clone2(fn, stack, stack_size, flags | SIGCHLD, NULL, pidfd);
-#else
- return clone(fn, stack + stack_size, flags | SIGCHLD, NULL, pidfd);
-#endif
-}
-
static int signal_received;
static void set_signal_received_on_sigusr1(int sig)
--
2.21.0
