@@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-or-later
CFLAGS += -Wall -O2 -g $(KHDR_INCLUDES)
-TEST_GEN_PROGS := statmount_test
+TEST_GEN_PROGS := statmount_test statmount_test_ns
include ../../lib.mk
new file mode 100644
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __STATMOUNT_H
+#define __STATMOUNT_H
+
+#include <stdint.h>
+#include <linux/mount.h>
+#include <asm/unistd.h>
+
+static inline int statmount(uint64_t mnt_id, uint64_t mnt_ns_id, uint64_t mask,
+ struct statmount *buf, size_t bufsize,
+ unsigned int flags)
+{
+ struct mnt_id_req req = {
+ .size = MNT_ID_REQ_SIZE_VER0,
+ .mnt_id = mnt_id,
+ .param = mask,
+ };
+
+ if (mnt_ns_id) {
+ req.size = MNT_ID_REQ_SIZE_VER1;
+ req.mnt_ns_id = mnt_ns_id;
+ }
+
+ return syscall(__NR_statmount, &req, buf, bufsize, flags);
+}
+
+static ssize_t listmount(uint64_t mnt_id, uint64_t mnt_ns_id,
+ uint64_t last_mnt_id, uint64_t list[], size_t num,
+ unsigned int flags)
+{
+ struct mnt_id_req req = {
+ .size = MNT_ID_REQ_SIZE_VER0,
+ .mnt_id = mnt_id,
+ .param = last_mnt_id,
+ };
+
+ if (mnt_ns_id) {
+ req.size = MNT_ID_REQ_SIZE_VER1;
+ req.mnt_ns_id = mnt_ns_id;
+ }
+
+ return syscall(__NR_listmount, &req, list, num, flags);
+}
+
+#endif /* __STATMOUNT_H */
@@ -4,17 +4,15 @@
#include <assert.h>
#include <stddef.h>
-#include <stdint.h>
#include <sched.h>
#include <fcntl.h>
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/statfs.h>
-#include <linux/mount.h>
#include <linux/stat.h>
-#include <asm/unistd.h>
+#include "statmount.h"
#include "../../kselftest.h"
static const char *const known_fs[] = {
@@ -36,18 +34,6 @@ static const char *const known_fs[] = {
"ufs", "v7", "vboxsf", "vfat", "virtiofs", "vxfs", "xenfs", "xfs",
"zonefs", NULL };
-static int statmount(uint64_t mnt_id, uint64_t mask, struct statmount *buf,
- size_t bufsize, unsigned int flags)
-{
- struct mnt_id_req req = {
- .size = MNT_ID_REQ_SIZE_VER0,
- .mnt_id = mnt_id,
- .param = mask,
- };
-
- return syscall(__NR_statmount, &req, buf, bufsize, flags);
-}
-
static struct statmount *statmount_alloc(uint64_t mnt_id, uint64_t mask, unsigned int flags)
{
size_t bufsize = 1 << 15;
@@ -56,7 +42,7 @@ static struct statmount *statmount_alloc(uint64_t mnt_id, uint64_t mask, unsigne
int ret;
for (;;) {
- ret = statmount(mnt_id, mask, tmp, bufsize, flags);
+ ret = statmount(mnt_id, 0, mask, tmp, bufsize, flags);
if (ret != -1)
break;
if (tofree)
@@ -122,7 +108,6 @@ static int orig_root;
static uint64_t root_id, parent_id;
static uint32_t old_root_id, old_parent_id;
-
static void cleanup_namespace(void)
{
fchdir(orig_root);
@@ -138,7 +123,7 @@ static void setup_namespace(void)
uid_t uid = getuid();
gid_t gid = getgid();
- ret = unshare(CLONE_NEWNS|CLONE_NEWUSER);
+ ret = unshare(CLONE_NEWNS|CLONE_NEWUSER|CLONE_NEWPID);
if (ret == -1)
ksft_exit_fail_msg("unsharing mountns and userns: %s\n",
strerror(errno));
@@ -208,25 +193,13 @@ static int setup_mount_tree(int log2_num)
return 0;
}
-static ssize_t listmount(uint64_t mnt_id, uint64_t last_mnt_id,
- uint64_t list[], size_t num, unsigned int flags)
-{
- struct mnt_id_req req = {
- .size = MNT_ID_REQ_SIZE_VER0,
- .mnt_id = mnt_id,
- .param = last_mnt_id,
- };
-
- return syscall(__NR_listmount, &req, list, num, flags);
-}
-
static void test_listmount_empty_root(void)
{
ssize_t res;
const unsigned int size = 32;
uint64_t list[size];
- res = listmount(LSMT_ROOT, 0, list, size, 0);
+ res = listmount(LSMT_ROOT, 0, 0, list, size, 0);
if (res == -1) {
ksft_test_result_fail("listmount: %s\n", strerror(errno));
return;
@@ -251,7 +224,7 @@ static void test_statmount_zero_mask(void)
struct statmount sm;
int ret;
- ret = statmount(root_id, 0, &sm, sizeof(sm), 0);
+ ret = statmount(root_id, 0, 0, &sm, sizeof(sm), 0);
if (ret == -1) {
ksft_test_result_fail("statmount zero mask: %s\n",
strerror(errno));
@@ -277,7 +250,7 @@ static void test_statmount_mnt_basic(void)
int ret;
uint64_t mask = STATMOUNT_MNT_BASIC;
- ret = statmount(root_id, mask, &sm, sizeof(sm), 0);
+ ret = statmount(root_id, 0, mask, &sm, sizeof(sm), 0);
if (ret == -1) {
ksft_test_result_fail("statmount mnt basic: %s\n",
strerror(errno));
@@ -337,7 +310,7 @@ static void test_statmount_sb_basic(void)
struct statx sx;
struct statfs sf;
- ret = statmount(root_id, mask, &sm, sizeof(sm), 0);
+ ret = statmount(root_id, 0, mask, &sm, sizeof(sm), 0);
if (ret == -1) {
ksft_test_result_fail("statmount sb basic: %s\n",
strerror(errno));
@@ -498,14 +471,14 @@ static void test_statmount_string(uint64_t mask, size_t off, const char *name)
exactsize = sm->size;
shortsize = sizeof(*sm) + i;
- ret = statmount(root_id, mask, sm, exactsize, 0);
+ ret = statmount(root_id, 0, mask, sm, exactsize, 0);
if (ret == -1) {
ksft_test_result_fail("statmount exact size: %s\n",
strerror(errno));
goto out;
}
errno = 0;
- ret = statmount(root_id, mask, sm, shortsize, 0);
+ ret = statmount(root_id, 0, mask, sm, shortsize, 0);
if (ret != -1 || errno != EOVERFLOW) {
ksft_test_result_fail("should have failed with EOVERFLOW: %s\n",
strerror(errno));
@@ -533,7 +506,7 @@ static void test_listmount_tree(void)
if (res == -1)
return;
- num = res = listmount(LSMT_ROOT, 0, list, size, 0);
+ num = res = listmount(LSMT_ROOT, 0, 0, list, size, 0);
if (res == -1) {
ksft_test_result_fail("listmount: %s\n", strerror(errno));
return;
@@ -545,7 +518,7 @@ static void test_listmount_tree(void)
}
for (i = 0; i < size - step;) {
- res = listmount(LSMT_ROOT, i ? list2[i - 1] : 0, list2 + i, step, 0);
+ res = listmount(LSMT_ROOT, 0, i ? list2[i - 1] : 0, list2 + i, step, 0);
if (res == -1)
ksft_test_result_fail("short listmount: %s\n",
strerror(errno));
@@ -577,11 +550,11 @@ int main(void)
int ret;
uint64_t all_mask = STATMOUNT_SB_BASIC | STATMOUNT_MNT_BASIC |
STATMOUNT_PROPAGATE_FROM | STATMOUNT_MNT_ROOT |
- STATMOUNT_MNT_POINT | STATMOUNT_FS_TYPE;
+ STATMOUNT_MNT_POINT | STATMOUNT_FS_TYPE | STATMOUNT_MNT_NS_ID;
ksft_print_header();
- ret = statmount(0, 0, NULL, 0, 0);
+ ret = statmount(0, 0, 0, NULL, 0, 0);
assert(ret == -1);
if (errno == ENOSYS)
ksft_exit_skip("statmount() syscall not supported\n");
new file mode 100644
@@ -0,0 +1,360 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <sched.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <linux/nsfs.h>
+#include <linux/stat.h>
+
+#include "statmount.h"
+#include "../../kselftest.h"
+
+#define NSID_PASS 0
+#define NSID_FAIL 1
+#define NSID_SKIP 2
+#define NSID_ERROR 3
+
+static void handle_result(int ret, const char *testname)
+{
+ if (ret == NSID_PASS)
+ ksft_test_result_pass(testname);
+ else if (ret == NSID_FAIL)
+ ksft_test_result_fail(testname);
+ else if (ret == NSID_ERROR)
+ ksft_exit_fail_msg(testname);
+ else
+ ksft_test_result_skip(testname);
+}
+
+static inline int wait_for_pid(pid_t pid)
+{
+ int status, ret;
+
+again:
+ ret = waitpid(pid, &status, 0);
+ if (ret == -1) {
+ if (errno == EINTR)
+ goto again;
+
+ ksft_print_msg("waitpid returned -1, errno=%d\n", errno);
+ return -1;
+ }
+
+ if (!WIFEXITED(status)) {
+ ksft_print_msg(
+ "waitpid !WIFEXITED, WIFSIGNALED=%d, WTERMSIG=%d\n",
+ WIFSIGNALED(status), WTERMSIG(status));
+ return -1;
+ }
+
+ ret = WEXITSTATUS(status);
+ return ret;
+}
+
+static int get_mnt_ns_id(const char *mnt_ns, uint64_t *mnt_ns_id)
+{
+ int fd = open(mnt_ns, O_RDONLY);
+
+ if (fd < 0) {
+ ksft_print_msg("failed to open for ns %s: %s\n",
+ mnt_ns, strerror(errno));
+ sleep(60);
+ return NSID_ERROR;
+ }
+
+ if (ioctl(fd, NS_GET_MNTNS_ID, mnt_ns_id) < 0) {
+ ksft_print_msg("failed to get the nsid for ns %s: %s\n",
+ mnt_ns, strerror(errno));
+ return NSID_ERROR;
+ }
+ close(fd);
+ return NSID_PASS;
+}
+
+static int get_mnt_id(const char *path, uint64_t *mnt_id)
+{
+ struct statx sx;
+ int ret;
+
+ ret = statx(AT_FDCWD, path, 0, STATX_MNT_ID_UNIQUE, &sx);
+ if (ret == -1) {
+ ksft_print_msg("retrieving unique mount ID for %s: %s\n", path,
+ strerror(errno));
+ return NSID_ERROR;
+ }
+
+ if (!(sx.stx_mask & STATX_MNT_ID_UNIQUE)) {
+ ksft_print_msg("no unique mount ID available for %s\n", path);
+ return NSID_ERROR;
+ }
+
+ *mnt_id = sx.stx_mnt_id;
+ return NSID_PASS;
+}
+
+static int write_file(const char *path, const char *val)
+{
+ int fd = open(path, O_WRONLY);
+ size_t len = strlen(val);
+ int ret;
+
+ if (fd == -1) {
+ ksft_print_msg("opening %s for write: %s\n", path, strerror(errno));
+ return NSID_ERROR;
+ }
+
+ ret = write(fd, val, len);
+ if (ret == -1) {
+ ksft_print_msg("writing to %s: %s\n", path, strerror(errno));
+ return NSID_ERROR;
+ }
+ if (ret != len) {
+ ksft_print_msg("short write to %s\n", path);
+ return NSID_ERROR;
+ }
+
+ ret = close(fd);
+ if (ret == -1) {
+ ksft_print_msg("closing %s\n", path);
+ return NSID_ERROR;
+ }
+
+ return NSID_PASS;
+}
+
+static int setup_namespace(void)
+{
+ int ret;
+ char buf[32];
+ uid_t uid = getuid();
+ gid_t gid = getgid();
+
+ ret = unshare(CLONE_NEWNS|CLONE_NEWUSER|CLONE_NEWPID);
+ if (ret == -1)
+ ksft_exit_fail_msg("unsharing mountns and userns: %s\n",
+ strerror(errno));
+
+ sprintf(buf, "0 %d 1", uid);
+ ret = write_file("/proc/self/uid_map", buf);
+ if (ret != NSID_PASS)
+ return ret;
+ ret = write_file("/proc/self/setgroups", "deny");
+ if (ret != NSID_PASS)
+ return ret;
+ sprintf(buf, "0 %d 1", gid);
+ ret = write_file("/proc/self/gid_map", buf);
+ if (ret != NSID_PASS)
+ return ret;
+
+ ret = mount("", "/", NULL, MS_REC|MS_PRIVATE, NULL);
+ if (ret == -1) {
+ ksft_print_msg("making mount tree private: %s\n",
+ strerror(errno));
+ return NSID_ERROR;
+ }
+
+ return NSID_PASS;
+}
+
+static int _test_statmount_mnt_ns_id(void)
+{
+ struct statmount sm;
+ uint64_t mnt_ns_id;
+ uint64_t root_id;
+ int ret;
+
+ ret = get_mnt_ns_id("/proc/self/ns/mnt", &mnt_ns_id);
+ if (ret != NSID_PASS)
+ return ret;
+
+ ret = get_mnt_id("/", &root_id);
+ if (ret != NSID_PASS)
+ return ret;
+
+ ret = statmount(root_id, 0, STATMOUNT_MNT_NS_ID, &sm, sizeof(sm), 0);
+ if (ret == -1) {
+ ksft_print_msg("statmount mnt ns id: %s\n", strerror(errno));
+ return NSID_ERROR;
+ }
+
+ if (sm.size != sizeof(sm)) {
+ ksft_print_msg("unexpected size: %u != %u\n", sm.size,
+ (uint32_t)sizeof(sm));
+ return NSID_FAIL;
+ }
+ if (sm.mask != STATMOUNT_MNT_NS_ID) {
+ ksft_print_msg("statmount mnt ns id unavailable\n");
+ return NSID_SKIP;
+ }
+
+ if (sm.mnt_ns_id != mnt_ns_id) {
+ ksft_print_msg("unexpected mnt ns ID: 0x%llx != 0x%llx\n",
+ (unsigned long long)sm.mnt_ns_id,
+ (unsigned long long)mnt_ns_id);
+ return NSID_FAIL;
+ }
+
+ return NSID_PASS;
+}
+
+static void test_statmount_mnt_ns_id(void)
+{
+ pid_t pid;
+ int ret;
+
+ pid = fork();
+ if (pid < 0)
+ ksft_exit_fail_msg("failed to fork: %s\n", strerror(errno));
+
+ /* We're the original pid, wait for the result. */
+ if (pid != 0) {
+ ret = wait_for_pid(pid);
+ handle_result(ret, "test statmount ns id\n");
+ return;
+ }
+
+ ret = setup_namespace();
+ if (ret != NSID_PASS)
+ exit(ret);
+ ret = _test_statmount_mnt_ns_id();
+ exit(ret);
+}
+
+static int validate_external_listmount(pid_t pid, uint64_t child_nr_mounts)
+{
+ uint64_t list[256];
+ uint64_t mnt_ns_id;
+ uint64_t nr_mounts;
+ char buf[256];
+ int ret;
+
+ /* Get the mount ns id for our child. */
+ snprintf(buf, sizeof(buf), "/proc/%lu/ns/mnt", (unsigned long)pid);
+ ret = get_mnt_ns_id(buf, &mnt_ns_id);
+
+ nr_mounts = listmount(LSMT_ROOT, mnt_ns_id, 0, list, 256, 0);
+ if (nr_mounts == (uint64_t)-1) {
+ ksft_print_msg("listmount: %s\n", strerror(errno));
+ return NSID_ERROR;
+ }
+
+ if (nr_mounts != child_nr_mounts) {
+ ksft_print_msg("listmount results is %zi != %zi\n", nr_mounts,
+ child_nr_mounts);
+ return NSID_FAIL;
+ }
+
+ /* Validate that all of our entries match our mnt_ns_id. */
+ for (int i = 0; i < nr_mounts; i++) {
+ struct statmount sm;
+
+ ret = statmount(list[i], mnt_ns_id, STATMOUNT_MNT_NS_ID, &sm,
+ sizeof(sm), 0);
+ if (ret < 0) {
+ ksft_print_msg("statmount mnt ns id: %s\n", strerror(errno));
+ return NSID_ERROR;
+ }
+
+ if (sm.mask != STATMOUNT_MNT_NS_ID) {
+ ksft_print_msg("statmount mnt ns id unavailable\n");
+ return NSID_SKIP;
+ }
+
+ if (sm.mnt_ns_id != mnt_ns_id) {
+ ksft_print_msg("listmount gave us the wrong ns id: 0x%llx != 0x%llx\n",
+ (unsigned long long)sm.mnt_ns_id,
+ (unsigned long long)mnt_ns_id);
+ return NSID_FAIL;
+ }
+ }
+
+ return NSID_PASS;
+}
+
+static void test_listmount_ns(void)
+{
+ uint64_t nr_mounts;
+ char pval;
+ int child_ready_pipe[2];
+ int parent_ready_pipe[2];
+ pid_t pid;
+ int ret, child_ret;
+
+ if (pipe(child_ready_pipe) < 0)
+ ksft_exit_fail_msg("failed to create the child pipe: %s\n",
+ strerror(errno));
+ if (pipe(parent_ready_pipe) < 0)
+ ksft_exit_fail_msg("failed to create the parent pipe: %s\n",
+ strerror(errno));
+
+ pid = fork();
+ if (pid < 0)
+ ksft_exit_fail_msg("failed to fork: %s\n", strerror(errno));
+
+ if (pid == 0) {
+ char cval;
+ uint64_t list[256];
+
+ close(child_ready_pipe[0]);
+ close(parent_ready_pipe[1]);
+
+ ret = setup_namespace();
+ if (ret != NSID_PASS)
+ exit(ret);
+
+ nr_mounts = listmount(LSMT_ROOT, 0, 0, list, 256, 0);
+ if (nr_mounts == (uint64_t)-1) {
+ ksft_print_msg("listmount: %s\n", strerror(errno));
+ exit(NSID_FAIL);
+ }
+
+ /*
+ * Tell our parent how many mounts we have, and then wait for it
+ * to tell us we're done.
+ */
+ write(child_ready_pipe[1], &nr_mounts, sizeof(nr_mounts));
+ read(parent_ready_pipe[0], &cval, sizeof(cval));
+ exit(NSID_PASS);
+ }
+
+ close(child_ready_pipe[1]);
+ close(parent_ready_pipe[0]);
+
+ /* Wait until the child has created everything. */
+ read(child_ready_pipe[0], &nr_mounts, sizeof(nr_mounts));
+
+ ret = validate_external_listmount(pid, nr_mounts);
+
+ write(parent_ready_pipe[1], &pval, sizeof(pval));
+ child_ret = wait_for_pid(pid);
+ if (child_ret != NSID_PASS)
+ ret = child_ret;
+ handle_result(ret, "test listmount ns id\n");
+}
+
+int main(void)
+{
+ int ret;
+
+ ksft_print_header();
+ ret = statmount(0, 0, 0, NULL, 0, 0);
+ assert(ret == -1);
+ if (errno == ENOSYS)
+ ksft_exit_skip("statmount() syscall not supported\n");
+
+ ksft_set_plan(2);
+ test_statmount_mnt_ns_id();
+ test_listmount_ns();
+
+ if (ksft_get_fail_cnt() + ksft_get_error_cnt() > 0)
+ ksft_exit_fail();
+ else
+ ksft_exit_pass();
+}
This tests both statmount and listmount to make sure they work with the extensions that allow us to specify a mount ns to enter in order to find the mount entries. Signed-off-by: Josef Bacik <josef@toxicpanda.com> --- .../selftests/filesystems/statmount/Makefile | 2 +- .../filesystems/statmount/statmount.h | 46 +++ .../filesystems/statmount/statmount_test.c | 53 +-- .../filesystems/statmount/statmount_test_ns.c | 360 ++++++++++++++++++ 4 files changed, 420 insertions(+), 41 deletions(-) create mode 100644 tools/testing/selftests/filesystems/statmount/statmount.h create mode 100644 tools/testing/selftests/filesystems/statmount/statmount_test_ns.c