From: Christian Brauner <christian.brauner@ubuntu.com> To: Alexander Viro <viro@zeniv.linux.org.uk>, Christoph Hellwig <hch@infradead.org>, linux-fsdevel@vger.kernel.org Cc: Andy Lutomirski <luto@kernel.org>, Mimi Zohar <zohar@linux.ibm.com>, James Bottomley <James.Bottomley@hansenpartnership.com>, Andreas Dilger <adilger.kernel@dilger.ca>, containers@lists.linux-foundation.org, Christoph Hellwig <hch@lst.de>, Tycho Andersen <tycho@tycho.ws>, Paul Moore <paul@paul-moore.com>, Jonathan Corbet <corbet@lwn.net>, smbarber@chromium.org, linux-ext4@vger.kernel.org, Mrunal Patel <mpatel@redhat.com>, Kees Cook <keescook@chromium.org>, Arnd Bergmann <arnd@arndb.de>, selinux@vger.kernel.org, Josh Triplett <josh@joshtriplett.org>, Seth Forshee <seth.forshee@canonical.com>, Aleksa Sarai <cyphar@cyphar.com>, Lennart Poettering <lennart@poettering.net>, OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>, Geoffrey Thomas <geofft@ldpreload.com>, David Howells <dhowells@redhat.com>, John Johansen <john.johansen@canonical.com>, Theodore Tso <tytso@mit.edu>, Dmitry Kasatkin <dmitry.kasatkin@gmail.com>, Stephen Smalley <stephen.smalley.work@gmail.com>, linux-security-module@vger.kernel.org, "Eric W. Biederman" <ebiederm@xmission.com>, linux-api@vger.kernel.org, Casey Schaufler <casey@schaufler-ca.com>, Alban Crequy <alban@kinvolk.io>, linux-integrity@vger.kernel.org, Todd Kjos <tkjos@google.com> Subject: [PATCH v4 07/40] tests: add mount_setattr() selftests Date: Fri, 4 Dec 2020 00:57:03 +0100 [thread overview] Message-ID: <20201203235736.3528991-8-christian.brauner@ubuntu.com> (raw) In-Reply-To: <20201203235736.3528991-1-christian.brauner@ubuntu.com> Add a range of selftests for the new mount_setattr() syscall to verify that it works as expected. This tests that: - no invalid flags can be specified - changing properties of a single mount works and leaves other mounts in the mount tree unchanged - changing a mount tre to read-only when one of the mounts has writers fails and leaves the whole mount tree unchanged - changing mount properties from multiple threads works - changing atime settings works - changing mount propagation works - changing the mount options of a mount tree where the individual mounts in the tree have different mount options only changes the flags that were requested to change - changing mount options from another mount namespace fails - changing mount options from another user namespace fails [==========] Running 9 tests from 2 test cases. [ RUN ] mount_setattr.invalid_attributes [ OK ] mount_setattr.invalid_attributes [ RUN ] mount_setattr.basic [ OK ] mount_setattr.basic [ RUN ] mount_setattr.basic_recursive [ OK ] mount_setattr.basic_recursive [ RUN ] mount_setattr.mount_has_writers [ OK ] mount_setattr.mount_has_writers [ RUN ] mount_setattr.mixed_mount_options [ OK ] mount_setattr.mixed_mount_options [ RUN ] mount_setattr.time_changes [ OK ] mount_setattr.time_changes [ RUN ] mount_setattr.multi_threaded [ OK ] mount_setattr.multi_threaded [ RUN ] mount_setattr.wrong_user_namespace [ OK ] mount_setattr.wrong_user_namespace [ RUN ] mount_setattr.wrong_mount_namespace [ OK ] mount_setattr.wrong_mount_namespace [==========] 9 / 9 tests passed. [ PASSED ] Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> --- /* v2 */ unchanged /* v3 */ unchanged /* v4 */ unchanged --- tools/testing/selftests/Makefile | 1 + .../selftests/mount_setattr/.gitignore | 1 + .../testing/selftests/mount_setattr/Makefile | 7 + tools/testing/selftests/mount_setattr/config | 1 + .../mount_setattr/mount_setattr_test.c | 941 ++++++++++++++++++ 5 files changed, 951 insertions(+) create mode 100644 tools/testing/selftests/mount_setattr/.gitignore create mode 100644 tools/testing/selftests/mount_setattr/Makefile create mode 100644 tools/testing/selftests/mount_setattr/config create mode 100644 tools/testing/selftests/mount_setattr/mount_setattr_test.c diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index d9c283503159..87b7107dd9a6 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -34,6 +34,7 @@ TARGETS += memfd TARGETS += memory-hotplug TARGETS += mincore TARGETS += mount +TARGETS += mount_setattr TARGETS += mqueue TARGETS += net TARGETS += net/forwarding diff --git a/tools/testing/selftests/mount_setattr/.gitignore b/tools/testing/selftests/mount_setattr/.gitignore new file mode 100644 index 000000000000..5f74d8488472 --- /dev/null +++ b/tools/testing/selftests/mount_setattr/.gitignore @@ -0,0 +1 @@ +mount_setattr_test diff --git a/tools/testing/selftests/mount_setattr/Makefile b/tools/testing/selftests/mount_setattr/Makefile new file mode 100644 index 000000000000..2250f7dcb81e --- /dev/null +++ b/tools/testing/selftests/mount_setattr/Makefile @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0 +# Makefile for mount selftests. +CFLAGS = -g -I../../../../usr/include/ -Wall -O2 -pthread + +TEST_GEN_FILES += mount_setattr_test + +include ../lib.mk diff --git a/tools/testing/selftests/mount_setattr/config b/tools/testing/selftests/mount_setattr/config new file mode 100644 index 000000000000..416bd53ce982 --- /dev/null +++ b/tools/testing/selftests/mount_setattr/config @@ -0,0 +1 @@ +CONFIG_USER_NS=y diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c new file mode 100644 index 000000000000..32fdb192629c --- /dev/null +++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c @@ -0,0 +1,941 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <sched.h> +#include <stdio.h> +#include <errno.h> +#include <pthread.h> +#include <string.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/mount.h> +#include <sys/wait.h> +#include <sys/vfs.h> +#include <sys/statvfs.h> +#include <sys/sysinfo.h> +#include <stdlib.h> +#include <unistd.h> +#include <fcntl.h> +#include <grp.h> +#include <stdbool.h> +#include <stdarg.h> + +#include "../kselftest_harness.h" + +#ifndef CLONE_NEWNS +#define CLONE_NEWNS 0x00020000 +#endif + +#ifndef CLONE_NEWUSER +#define CLONE_NEWUSER 0x10000000 +#endif + +#ifndef MS_REC +#define MS_REC 16384 +#endif + +#ifndef MS_RELATIME +#define MS_RELATIME (1 << 21) +#endif + +#ifndef MS_STRICTATIME +#define MS_STRICTATIME (1 << 24) +#endif + +#ifndef MOUNT_ATTR_RDONLY +#define MOUNT_ATTR_RDONLY 0x00000001 +#endif + +#ifndef MOUNT_ATTR_NOSUID +#define MOUNT_ATTR_NOSUID 0x00000002 +#endif + +#ifndef MOUNT_ATTR_NOEXEC +#define MOUNT_ATTR_NOEXEC 0x00000008 +#endif + +#ifndef MOUNT_ATTR_NODIRATIME +#define MOUNT_ATTR_NODIRATIME 0x00000080 +#endif + +#ifndef MOUNT_ATTR__ATIME +#define MOUNT_ATTR__ATIME 0x00000070 +#endif + +#ifndef MOUNT_ATTR_RELATIME +#define MOUNT_ATTR_RELATIME 0x00000000 +#endif + +#ifndef MOUNT_ATTR_NOATIME +#define MOUNT_ATTR_NOATIME 0x00000010 +#endif + +#ifndef MOUNT_ATTR_STRICTATIME +#define MOUNT_ATTR_STRICTATIME 0x00000020 +#endif + +#ifndef AT_RECURSIVE +#define AT_RECURSIVE 0x8000 +#endif + +#ifndef MS_SHARED +#define MS_SHARED (1 << 20) +#endif + +#define DEFAULT_THREADS 4 +#define ptr_to_int(p) ((int)((intptr_t)(p))) +#define int_to_ptr(u) ((void *)((intptr_t)(u))) + +#ifndef __NR_mount_setattr + #if defined __alpha__ + #define __NR_mount_setattr 551 + #elif defined _MIPS_SIM + #if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */ + #define __NR_mount_setattr 4441 + #endif + #if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */ + #define __NR_mount_setattr 6441 + #endif + #if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */ + #define __NR_mount_setattr 5441 + #endif + #elif defined __ia64__ + #define __NR_mount_setattr (441 + 1024) + #else + #define __NR_mount_setattr 441 + #endif + +struct mount_attr { + __u64 attr_set; + __u64 attr_clr; + __u64 propagation; +}; +#endif + +static inline int sys_mount_setattr(int dfd, const char *path, unsigned int flags, + struct mount_attr *attr, size_t size) +{ + return syscall(__NR_mount_setattr, dfd, path, flags, attr, size); +} + +static ssize_t write_nointr(int fd, const void *buf, size_t count) +{ + ssize_t ret; + + do { + ret = write(fd, buf, count); + } while (ret < 0 && errno == EINTR); + + return ret; +} + +static int write_file(const char *path, const void *buf, size_t count) +{ + int fd; + ssize_t ret; + + fd = open(path, O_WRONLY | O_CLOEXEC | O_NOCTTY | O_NOFOLLOW); + if (fd < 0) + return -1; + + ret = write_nointr(fd, buf, count); + close(fd); + if (ret < 0 || (size_t)ret != count) + return -1; + + return 0; +} + +static int create_and_enter_userns(void) +{ + uid_t uid; + gid_t gid; + char map[100]; + + uid = getuid(); + gid = getgid(); + + if (unshare(CLONE_NEWUSER)) + return -1; + + if (write_file("/proc/self/setgroups", "deny", sizeof("deny") - 1) && + errno != ENOENT) + return -1; + + snprintf(map, sizeof(map), "0 %d 1", uid); + if (write_file("/proc/self/uid_map", map, strlen(map))) + return -1; + + + snprintf(map, sizeof(map), "0 %d 1", gid); + if (write_file("/proc/self/gid_map", map, strlen(map))) + return -1; + + if (setgid(0)) + return -1; + + if (setuid(0)) + return -1; + + return 0; +} + +static int prepare_unpriv_mountns(void) +{ + if (create_and_enter_userns()) + return -1; + + if (unshare(CLONE_NEWNS)) + return -1; + + if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0)) + return -1; + + return 0; +} + +static int read_mnt_flags(const char *path) +{ + int ret; + struct statvfs stat; + unsigned int mnt_flags; + + ret = statvfs(path, &stat); + if (ret != 0) + return -EINVAL; + + if (stat.f_flag & + ~(ST_RDONLY | ST_NOSUID | ST_NODEV | ST_NOEXEC | ST_NOATIME | + ST_NODIRATIME | ST_RELATIME | ST_SYNCHRONOUS | ST_MANDLOCK)) + return -EINVAL; + + mnt_flags = 0; + if (stat.f_flag & ST_RDONLY) + mnt_flags |= MS_RDONLY; + if (stat.f_flag & ST_NOSUID) + mnt_flags |= MS_NOSUID; + if (stat.f_flag & ST_NODEV) + mnt_flags |= MS_NODEV; + if (stat.f_flag & ST_NOEXEC) + mnt_flags |= MS_NOEXEC; + if (stat.f_flag & ST_NOATIME) + mnt_flags |= MS_NOATIME; + if (stat.f_flag & ST_NODIRATIME) + mnt_flags |= MS_NODIRATIME; + if (stat.f_flag & ST_RELATIME) + mnt_flags |= MS_RELATIME; + if (stat.f_flag & ST_SYNCHRONOUS) + mnt_flags |= MS_SYNCHRONOUS; + if (stat.f_flag & ST_MANDLOCK) + mnt_flags |= ST_MANDLOCK; + + return mnt_flags; +} + +static char *get_field(char *src, int nfields) +{ + int i; + char *p = src; + + for (i = 0; i < nfields; i++) { + while (*p && *p != ' ' && *p != '\t') + p++; + + if (!*p) + break; + + p++; + } + + return p; +} + +static void null_endofword(char *word) +{ + while (*word && *word != ' ' && *word != '\t') + word++; + *word = '\0'; +} + +static bool is_shared_mount(const char *path) +{ + size_t len = 0; + char *line = NULL; + FILE *f = NULL; + + f = fopen("/proc/self/mountinfo", "re"); + if (!f) + return false; + + while (getline(&line, &len, f) != -1) { + char *opts, *target; + + target = get_field(line, 4); + if (!target) + continue; + + opts = get_field(target, 2); + if (!opts) + continue; + + null_endofword(target); + + if (strcmp(target, path) != 0) + continue; + + null_endofword(opts); + if (strstr(opts, "shared:")) + return true; + } + + free(line); + fclose(f); + + return false; +} + +static void *mount_setattr_thread(void *data) +{ + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID, + .attr_clr = 0, + .propagation = MS_SHARED, + }; + + if (sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr))) + pthread_exit(int_to_ptr(-1)); + + pthread_exit(int_to_ptr(0)); +} + +/* Attempt to de-conflict with the selftests tree. */ +#ifndef SKIP +#define SKIP(s, ...) XFAIL(s, ##__VA_ARGS__) +#endif + +static bool mount_setattr_supported(void) +{ + int ret; + + ret = sys_mount_setattr(-EBADF, "", AT_EMPTY_PATH, NULL, 0); + if (ret < 0 && errno == ENOSYS) + return false; + + return true; +} + +FIXTURE(mount_setattr) { +}; + +FIXTURE_SETUP(mount_setattr) +{ + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + ASSERT_EQ(prepare_unpriv_mountns(), 0); + + (void)umount2("/mnt", MNT_DETACH); + (void)umount2("/tmp", MNT_DETACH); + + ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/tmp/B", 0777), 0); + + ASSERT_EQ(mount("testing", "/tmp/B", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/tmp/B/BB", 0777), 0); + + ASSERT_EQ(mount("testing", "/tmp/B/BB", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/mnt/A", 0777), 0); + + ASSERT_EQ(mount("testing", "/mnt/A", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/mnt/A/AA", 0777), 0); + + ASSERT_EQ(mount("/tmp", "/mnt/A/AA", NULL, MS_BIND | MS_REC, NULL), 0); + + ASSERT_EQ(mkdir("/mnt/B", 0777), 0); + + ASSERT_EQ(mount("testing", "/mnt/B", "ramfs", + MS_NOATIME | MS_NODEV | MS_NOSUID, 0), 0); + + ASSERT_EQ(mkdir("/mnt/B/BB", 0777), 0); + + ASSERT_EQ(mount("testing", "/tmp/B/BB", "devpts", + MS_RELATIME | MS_NOEXEC | MS_RDONLY, 0), 0); +} + +FIXTURE_TEARDOWN(mount_setattr) +{ + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + (void)umount2("/mnt/A", MNT_DETACH); + (void)umount2("/tmp", MNT_DETACH); +} + +TEST_F(mount_setattr, invalid_attributes) +{ + struct mount_attr invalid_attr = { + .attr_set = (1U << 31), + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + invalid_attr.attr_set = 0; + invalid_attr.attr_clr = (1U << 31); + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + invalid_attr.attr_clr = 0; + invalid_attr.propagation = (1U << 31); + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + invalid_attr.attr_set = (1U << 31); + invalid_attr.attr_clr = (1U << 31); + invalid_attr.propagation = (1U << 31); + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + ASSERT_NE(sys_mount_setattr(-1, "mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); +} + +TEST_F(mount_setattr, extensibility) +{ + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + char *s = "dummy"; + struct mount_attr invalid_attr = {}; + struct mount_attr_large { + struct mount_attr attr1; + struct mount_attr attr2; + struct mount_attr attr3; + } large_attr = {}; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, NULL, + sizeof(invalid_attr)), 0); + ASSERT_EQ(errno, EFAULT); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, (void *)s, + sizeof(invalid_attr)), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, 0), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr) / 2), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr) / 2), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, + (void *)&large_attr, sizeof(large_attr)), 0); + + large_attr.attr3.attr_set = MOUNT_ATTR_RDONLY; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, + (void *)&large_attr, sizeof(large_attr)), 0); + + large_attr.attr3.attr_set = 0; + large_attr.attr1.attr_set = MOUNT_ATTR_RDONLY; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, + (void *)&large_attr, sizeof(large_attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); +} + +TEST_F(mount_setattr, basic) +{ + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME, + .attr_clr = MOUNT_ATTR__ATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", 0, &attr, sizeof(attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + expected_flags |= MS_NOEXEC; + expected_flags &= ~MS_NOATIME; + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, old_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, old_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, old_flags); +} + +TEST_F(mount_setattr, basic_recursive) +{ + int fd; + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME, + .attr_clr = MOUNT_ATTR__ATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + expected_flags |= MS_NOEXEC; + expected_flags &= ~MS_NOATIME; + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_clr = MOUNT_ATTR_RDONLY; + attr.propagation = MS_SHARED; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_RDONLY; + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), true); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true); + + fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777); + ASSERT_GE(fd, 0); + + /* + * We're holding a fd open for writing so this needs to fail somewhere + * in the middle and the mount options need to be unchanged. + */ + attr.attr_set = MOUNT_ATTR_RDONLY; + ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), true); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true); + + EXPECT_EQ(close(fd), 0); +} + +TEST_F(mount_setattr, mount_has_writers) +{ + int fd, dfd; + unsigned int old_flags = 0, new_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME, + .attr_clr = MOUNT_ATTR__ATIME, + .propagation = MS_SHARED, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777); + ASSERT_GE(fd, 0); + + /* + * We're holding a fd open to a mount somwhere in the middle so this + * needs to fail somewhere in the middle. After this the mount options + * need to be unchanged. + */ + ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), false); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), false); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), false); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), false); + + dfd = open("/mnt/A/AA/B", O_DIRECTORY | O_CLOEXEC); + ASSERT_GE(dfd, 0); + EXPECT_EQ(fsync(dfd), 0); + EXPECT_EQ(close(dfd), 0); + + EXPECT_EQ(fsync(fd), 0); + EXPECT_EQ(close(fd), 0); + + /* All writers are gone so this should succeed. */ + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); +} + +TEST_F(mount_setattr, mixed_mount_options) +{ + unsigned int old_flags1 = 0, old_flags2 = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_clr = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME, + .attr_set = MOUNT_ATTR_RELATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags1 = read_mnt_flags("/mnt/B"); + ASSERT_GT(old_flags1, 0); + + old_flags2 = read_mnt_flags("/mnt/B/BB"); + ASSERT_GT(old_flags2, 0); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/B", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags = old_flags2; + expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID); + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/B"); + ASSERT_EQ(new_flags, expected_flags); + + expected_flags = old_flags2; + expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID); + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/B/BB"); + ASSERT_EQ(new_flags, expected_flags); +} + +TEST_F(mount_setattr, time_changes) +{ + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = MOUNT_ATTR_STRICTATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME; + attr.attr_clr = MOUNT_ATTR__ATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = 0; + attr.attr_clr = MOUNT_ATTR_STRICTATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_clr = MOUNT_ATTR_NOATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + attr.attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME; + attr.attr_clr = MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_NOATIME; + expected_flags |= MS_NODIRATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_set &= ~MOUNT_ATTR_NOATIME; + attr.attr_set |= MOUNT_ATTR_RELATIME; + attr.attr_clr |= MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_NOATIME; + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_set &= ~MOUNT_ATTR_RELATIME; + attr.attr_set |= MOUNT_ATTR_STRICTATIME; + attr.attr_clr |= MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_set &= ~MOUNT_ATTR_STRICTATIME; + attr.attr_set |= MOUNT_ATTR_NOATIME; + attr.attr_clr |= MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags |= MS_NOATIME; + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_clr = MOUNT_ATTR_NODIRATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_NODIRATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); +} + +TEST_F(mount_setattr, multi_threaded) +{ + int i, j, nthreads, ret = 0; + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + pthread_attr_t pattr; + pthread_t threads[DEFAULT_THREADS]; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + /* Try to change mount options from multiple threads. */ + nthreads = get_nprocs_conf(); + if (nthreads > DEFAULT_THREADS) + nthreads = DEFAULT_THREADS; + + pthread_attr_init(&pattr); + for (i = 0; i < nthreads; i++) + ASSERT_EQ(pthread_create(&threads[i], &pattr, mount_setattr_thread, NULL), 0); + + for (j = 0; j < i; j++) { + void *retptr = NULL; + + EXPECT_EQ(pthread_join(threads[j], &retptr), 0); + + ret += ptr_to_int(retptr); + EXPECT_EQ(ret, 0); + } + pthread_attr_destroy(&pattr); + + ASSERT_EQ(ret, 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + expected_flags |= MS_NOSUID; + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), true); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true); +} + +TEST_F(mount_setattr, wrong_user_namespace) +{ + int ret; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + EXPECT_EQ(create_and_enter_userns(), 0); + ret = sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)); + ASSERT_LT(ret, 0); + ASSERT_EQ(errno, EPERM); +} + +TEST_F(mount_setattr, wrong_mount_namespace) +{ + int fd, ret; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + fd = open("/mnt/A", O_DIRECTORY | O_CLOEXEC); + ASSERT_GE(fd, 0); + + ASSERT_EQ(unshare(CLONE_NEWNS), 0); + + ret = sys_mount_setattr(fd, "", AT_EMPTY_PATH | AT_RECURSIVE, &attr, sizeof(attr)); + ASSERT_LT(ret, 0); + ASSERT_EQ(errno, EINVAL); +} + +TEST_HARNESS_MAIN -- 2.29.2 _______________________________________________ Containers mailing list Containers@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/containers
WARNING: multiple messages have this Message-ID (diff)
From: Christian Brauner <christian.brauner@ubuntu.com> To: Alexander Viro <viro@zeniv.linux.org.uk>, Christoph Hellwig <hch@infradead.org>, linux-fsdevel@vger.kernel.org Cc: "John Johansen" <john.johansen@canonical.com>, "James Morris" <jmorris@namei.org>, "Mimi Zohar" <zohar@linux.ibm.com>, "Dmitry Kasatkin" <dmitry.kasatkin@gmail.com>, "Stephen Smalley" <stephen.smalley.work@gmail.com>, "Casey Schaufler" <casey@schaufler-ca.com>, "Arnd Bergmann" <arnd@arndb.de>, "Andreas Dilger" <adilger.kernel@dilger.ca>, "OGAWA Hirofumi" <hirofumi@mail.parknet.co.jp>, "Geoffrey Thomas" <geofft@ldpreload.com>, "Mrunal Patel" <mpatel@redhat.com>, "Josh Triplett" <josh@joshtriplett.org>, "Andy Lutomirski" <luto@kernel.org>, "Theodore Tso" <tytso@mit.edu>, "Alban Crequy" <alban@kinvolk.io>, "Tycho Andersen" <tycho@tycho.ws>, "David Howells" <dhowells@redhat.com>, "James Bottomley" <James.Bottomley@hansenpartnership.com>, "Seth Forshee" <seth.forshee@canonical.com>, "Stéphane Graber" <stgraber@ubuntu.com>, "Aleksa Sarai" <cyphar@cyphar.com>, "Lennart Poettering" <lennart@poettering.net>, "Eric W. Biederman" <ebiederm@xmission.com>, smbarber@chromium.org, "Phil Estes" <estesp@gmail.com>, "Serge Hallyn" <serge@hallyn.com>, "Kees Cook" <keescook@chromium.org>, "Todd Kjos" <tkjos@google.com>, "Paul Moore" <paul@paul-moore.com>, "Jonathan Corbet" <corbet@lwn.net>, containers@lists.linux-foundation.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, linux-ext4@vger.kernel.org, linux-integrity@vger.kernel.org, selinux@vger.kernel.org, "Christian Brauner" <christian.brauner@ubuntu.com>, "Christoph Hellwig" <hch@lst.de> Subject: [PATCH v4 07/40] tests: add mount_setattr() selftests Date: Fri, 4 Dec 2020 00:57:03 +0100 [thread overview] Message-ID: <20201203235736.3528991-8-christian.brauner@ubuntu.com> (raw) In-Reply-To: <20201203235736.3528991-1-christian.brauner@ubuntu.com> Add a range of selftests for the new mount_setattr() syscall to verify that it works as expected. This tests that: - no invalid flags can be specified - changing properties of a single mount works and leaves other mounts in the mount tree unchanged - changing a mount tre to read-only when one of the mounts has writers fails and leaves the whole mount tree unchanged - changing mount properties from multiple threads works - changing atime settings works - changing mount propagation works - changing the mount options of a mount tree where the individual mounts in the tree have different mount options only changes the flags that were requested to change - changing mount options from another mount namespace fails - changing mount options from another user namespace fails [==========] Running 9 tests from 2 test cases. [ RUN ] mount_setattr.invalid_attributes [ OK ] mount_setattr.invalid_attributes [ RUN ] mount_setattr.basic [ OK ] mount_setattr.basic [ RUN ] mount_setattr.basic_recursive [ OK ] mount_setattr.basic_recursive [ RUN ] mount_setattr.mount_has_writers [ OK ] mount_setattr.mount_has_writers [ RUN ] mount_setattr.mixed_mount_options [ OK ] mount_setattr.mixed_mount_options [ RUN ] mount_setattr.time_changes [ OK ] mount_setattr.time_changes [ RUN ] mount_setattr.multi_threaded [ OK ] mount_setattr.multi_threaded [ RUN ] mount_setattr.wrong_user_namespace [ OK ] mount_setattr.wrong_user_namespace [ RUN ] mount_setattr.wrong_mount_namespace [ OK ] mount_setattr.wrong_mount_namespace [==========] 9 / 9 tests passed. [ PASSED ] Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> --- /* v2 */ unchanged /* v3 */ unchanged /* v4 */ unchanged --- tools/testing/selftests/Makefile | 1 + .../selftests/mount_setattr/.gitignore | 1 + .../testing/selftests/mount_setattr/Makefile | 7 + tools/testing/selftests/mount_setattr/config | 1 + .../mount_setattr/mount_setattr_test.c | 941 ++++++++++++++++++ 5 files changed, 951 insertions(+) create mode 100644 tools/testing/selftests/mount_setattr/.gitignore create mode 100644 tools/testing/selftests/mount_setattr/Makefile create mode 100644 tools/testing/selftests/mount_setattr/config create mode 100644 tools/testing/selftests/mount_setattr/mount_setattr_test.c diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index d9c283503159..87b7107dd9a6 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -34,6 +34,7 @@ TARGETS += memfd TARGETS += memory-hotplug TARGETS += mincore TARGETS += mount +TARGETS += mount_setattr TARGETS += mqueue TARGETS += net TARGETS += net/forwarding diff --git a/tools/testing/selftests/mount_setattr/.gitignore b/tools/testing/selftests/mount_setattr/.gitignore new file mode 100644 index 000000000000..5f74d8488472 --- /dev/null +++ b/tools/testing/selftests/mount_setattr/.gitignore @@ -0,0 +1 @@ +mount_setattr_test diff --git a/tools/testing/selftests/mount_setattr/Makefile b/tools/testing/selftests/mount_setattr/Makefile new file mode 100644 index 000000000000..2250f7dcb81e --- /dev/null +++ b/tools/testing/selftests/mount_setattr/Makefile @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0 +# Makefile for mount selftests. +CFLAGS = -g -I../../../../usr/include/ -Wall -O2 -pthread + +TEST_GEN_FILES += mount_setattr_test + +include ../lib.mk diff --git a/tools/testing/selftests/mount_setattr/config b/tools/testing/selftests/mount_setattr/config new file mode 100644 index 000000000000..416bd53ce982 --- /dev/null +++ b/tools/testing/selftests/mount_setattr/config @@ -0,0 +1 @@ +CONFIG_USER_NS=y diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c new file mode 100644 index 000000000000..32fdb192629c --- /dev/null +++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c @@ -0,0 +1,941 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <sched.h> +#include <stdio.h> +#include <errno.h> +#include <pthread.h> +#include <string.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/mount.h> +#include <sys/wait.h> +#include <sys/vfs.h> +#include <sys/statvfs.h> +#include <sys/sysinfo.h> +#include <stdlib.h> +#include <unistd.h> +#include <fcntl.h> +#include <grp.h> +#include <stdbool.h> +#include <stdarg.h> + +#include "../kselftest_harness.h" + +#ifndef CLONE_NEWNS +#define CLONE_NEWNS 0x00020000 +#endif + +#ifndef CLONE_NEWUSER +#define CLONE_NEWUSER 0x10000000 +#endif + +#ifndef MS_REC +#define MS_REC 16384 +#endif + +#ifndef MS_RELATIME +#define MS_RELATIME (1 << 21) +#endif + +#ifndef MS_STRICTATIME +#define MS_STRICTATIME (1 << 24) +#endif + +#ifndef MOUNT_ATTR_RDONLY +#define MOUNT_ATTR_RDONLY 0x00000001 +#endif + +#ifndef MOUNT_ATTR_NOSUID +#define MOUNT_ATTR_NOSUID 0x00000002 +#endif + +#ifndef MOUNT_ATTR_NOEXEC +#define MOUNT_ATTR_NOEXEC 0x00000008 +#endif + +#ifndef MOUNT_ATTR_NODIRATIME +#define MOUNT_ATTR_NODIRATIME 0x00000080 +#endif + +#ifndef MOUNT_ATTR__ATIME +#define MOUNT_ATTR__ATIME 0x00000070 +#endif + +#ifndef MOUNT_ATTR_RELATIME +#define MOUNT_ATTR_RELATIME 0x00000000 +#endif + +#ifndef MOUNT_ATTR_NOATIME +#define MOUNT_ATTR_NOATIME 0x00000010 +#endif + +#ifndef MOUNT_ATTR_STRICTATIME +#define MOUNT_ATTR_STRICTATIME 0x00000020 +#endif + +#ifndef AT_RECURSIVE +#define AT_RECURSIVE 0x8000 +#endif + +#ifndef MS_SHARED +#define MS_SHARED (1 << 20) +#endif + +#define DEFAULT_THREADS 4 +#define ptr_to_int(p) ((int)((intptr_t)(p))) +#define int_to_ptr(u) ((void *)((intptr_t)(u))) + +#ifndef __NR_mount_setattr + #if defined __alpha__ + #define __NR_mount_setattr 551 + #elif defined _MIPS_SIM + #if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */ + #define __NR_mount_setattr 4441 + #endif + #if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */ + #define __NR_mount_setattr 6441 + #endif + #if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */ + #define __NR_mount_setattr 5441 + #endif + #elif defined __ia64__ + #define __NR_mount_setattr (441 + 1024) + #else + #define __NR_mount_setattr 441 + #endif + +struct mount_attr { + __u64 attr_set; + __u64 attr_clr; + __u64 propagation; +}; +#endif + +static inline int sys_mount_setattr(int dfd, const char *path, unsigned int flags, + struct mount_attr *attr, size_t size) +{ + return syscall(__NR_mount_setattr, dfd, path, flags, attr, size); +} + +static ssize_t write_nointr(int fd, const void *buf, size_t count) +{ + ssize_t ret; + + do { + ret = write(fd, buf, count); + } while (ret < 0 && errno == EINTR); + + return ret; +} + +static int write_file(const char *path, const void *buf, size_t count) +{ + int fd; + ssize_t ret; + + fd = open(path, O_WRONLY | O_CLOEXEC | O_NOCTTY | O_NOFOLLOW); + if (fd < 0) + return -1; + + ret = write_nointr(fd, buf, count); + close(fd); + if (ret < 0 || (size_t)ret != count) + return -1; + + return 0; +} + +static int create_and_enter_userns(void) +{ + uid_t uid; + gid_t gid; + char map[100]; + + uid = getuid(); + gid = getgid(); + + if (unshare(CLONE_NEWUSER)) + return -1; + + if (write_file("/proc/self/setgroups", "deny", sizeof("deny") - 1) && + errno != ENOENT) + return -1; + + snprintf(map, sizeof(map), "0 %d 1", uid); + if (write_file("/proc/self/uid_map", map, strlen(map))) + return -1; + + + snprintf(map, sizeof(map), "0 %d 1", gid); + if (write_file("/proc/self/gid_map", map, strlen(map))) + return -1; + + if (setgid(0)) + return -1; + + if (setuid(0)) + return -1; + + return 0; +} + +static int prepare_unpriv_mountns(void) +{ + if (create_and_enter_userns()) + return -1; + + if (unshare(CLONE_NEWNS)) + return -1; + + if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0)) + return -1; + + return 0; +} + +static int read_mnt_flags(const char *path) +{ + int ret; + struct statvfs stat; + unsigned int mnt_flags; + + ret = statvfs(path, &stat); + if (ret != 0) + return -EINVAL; + + if (stat.f_flag & + ~(ST_RDONLY | ST_NOSUID | ST_NODEV | ST_NOEXEC | ST_NOATIME | + ST_NODIRATIME | ST_RELATIME | ST_SYNCHRONOUS | ST_MANDLOCK)) + return -EINVAL; + + mnt_flags = 0; + if (stat.f_flag & ST_RDONLY) + mnt_flags |= MS_RDONLY; + if (stat.f_flag & ST_NOSUID) + mnt_flags |= MS_NOSUID; + if (stat.f_flag & ST_NODEV) + mnt_flags |= MS_NODEV; + if (stat.f_flag & ST_NOEXEC) + mnt_flags |= MS_NOEXEC; + if (stat.f_flag & ST_NOATIME) + mnt_flags |= MS_NOATIME; + if (stat.f_flag & ST_NODIRATIME) + mnt_flags |= MS_NODIRATIME; + if (stat.f_flag & ST_RELATIME) + mnt_flags |= MS_RELATIME; + if (stat.f_flag & ST_SYNCHRONOUS) + mnt_flags |= MS_SYNCHRONOUS; + if (stat.f_flag & ST_MANDLOCK) + mnt_flags |= ST_MANDLOCK; + + return mnt_flags; +} + +static char *get_field(char *src, int nfields) +{ + int i; + char *p = src; + + for (i = 0; i < nfields; i++) { + while (*p && *p != ' ' && *p != '\t') + p++; + + if (!*p) + break; + + p++; + } + + return p; +} + +static void null_endofword(char *word) +{ + while (*word && *word != ' ' && *word != '\t') + word++; + *word = '\0'; +} + +static bool is_shared_mount(const char *path) +{ + size_t len = 0; + char *line = NULL; + FILE *f = NULL; + + f = fopen("/proc/self/mountinfo", "re"); + if (!f) + return false; + + while (getline(&line, &len, f) != -1) { + char *opts, *target; + + target = get_field(line, 4); + if (!target) + continue; + + opts = get_field(target, 2); + if (!opts) + continue; + + null_endofword(target); + + if (strcmp(target, path) != 0) + continue; + + null_endofword(opts); + if (strstr(opts, "shared:")) + return true; + } + + free(line); + fclose(f); + + return false; +} + +static void *mount_setattr_thread(void *data) +{ + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID, + .attr_clr = 0, + .propagation = MS_SHARED, + }; + + if (sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr))) + pthread_exit(int_to_ptr(-1)); + + pthread_exit(int_to_ptr(0)); +} + +/* Attempt to de-conflict with the selftests tree. */ +#ifndef SKIP +#define SKIP(s, ...) XFAIL(s, ##__VA_ARGS__) +#endif + +static bool mount_setattr_supported(void) +{ + int ret; + + ret = sys_mount_setattr(-EBADF, "", AT_EMPTY_PATH, NULL, 0); + if (ret < 0 && errno == ENOSYS) + return false; + + return true; +} + +FIXTURE(mount_setattr) { +}; + +FIXTURE_SETUP(mount_setattr) +{ + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + ASSERT_EQ(prepare_unpriv_mountns(), 0); + + (void)umount2("/mnt", MNT_DETACH); + (void)umount2("/tmp", MNT_DETACH); + + ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/tmp/B", 0777), 0); + + ASSERT_EQ(mount("testing", "/tmp/B", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/tmp/B/BB", 0777), 0); + + ASSERT_EQ(mount("testing", "/tmp/B/BB", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/mnt/A", 0777), 0); + + ASSERT_EQ(mount("testing", "/mnt/A", "tmpfs", MS_NOATIME | MS_NODEV, + "size=100000,mode=700"), 0); + + ASSERT_EQ(mkdir("/mnt/A/AA", 0777), 0); + + ASSERT_EQ(mount("/tmp", "/mnt/A/AA", NULL, MS_BIND | MS_REC, NULL), 0); + + ASSERT_EQ(mkdir("/mnt/B", 0777), 0); + + ASSERT_EQ(mount("testing", "/mnt/B", "ramfs", + MS_NOATIME | MS_NODEV | MS_NOSUID, 0), 0); + + ASSERT_EQ(mkdir("/mnt/B/BB", 0777), 0); + + ASSERT_EQ(mount("testing", "/tmp/B/BB", "devpts", + MS_RELATIME | MS_NOEXEC | MS_RDONLY, 0), 0); +} + +FIXTURE_TEARDOWN(mount_setattr) +{ + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + (void)umount2("/mnt/A", MNT_DETACH); + (void)umount2("/tmp", MNT_DETACH); +} + +TEST_F(mount_setattr, invalid_attributes) +{ + struct mount_attr invalid_attr = { + .attr_set = (1U << 31), + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + invalid_attr.attr_set = 0; + invalid_attr.attr_clr = (1U << 31); + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + invalid_attr.attr_clr = 0; + invalid_attr.propagation = (1U << 31); + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + invalid_attr.attr_set = (1U << 31); + invalid_attr.attr_clr = (1U << 31); + invalid_attr.propagation = (1U << 31); + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); + + ASSERT_NE(sys_mount_setattr(-1, "mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr)), 0); +} + +TEST_F(mount_setattr, extensibility) +{ + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + char *s = "dummy"; + struct mount_attr invalid_attr = {}; + struct mount_attr_large { + struct mount_attr attr1; + struct mount_attr attr2; + struct mount_attr attr3; + } large_attr = {}; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, NULL, + sizeof(invalid_attr)), 0); + ASSERT_EQ(errno, EFAULT); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, (void *)s, + sizeof(invalid_attr)), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, 0), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr) / 2), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, + sizeof(invalid_attr) / 2), 0); + ASSERT_EQ(errno, EINVAL); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, + (void *)&large_attr, sizeof(large_attr)), 0); + + large_attr.attr3.attr_set = MOUNT_ATTR_RDONLY; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, + (void *)&large_attr, sizeof(large_attr)), 0); + + large_attr.attr3.attr_set = 0; + large_attr.attr1.attr_set = MOUNT_ATTR_RDONLY; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, + (void *)&large_attr, sizeof(large_attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); +} + +TEST_F(mount_setattr, basic) +{ + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME, + .attr_clr = MOUNT_ATTR__ATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", 0, &attr, sizeof(attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + expected_flags |= MS_NOEXEC; + expected_flags &= ~MS_NOATIME; + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, old_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, old_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, old_flags); +} + +TEST_F(mount_setattr, basic_recursive) +{ + int fd; + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME, + .attr_clr = MOUNT_ATTR__ATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + expected_flags |= MS_NOEXEC; + expected_flags &= ~MS_NOATIME; + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_clr = MOUNT_ATTR_RDONLY; + attr.propagation = MS_SHARED; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_RDONLY; + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), true); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true); + + fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777); + ASSERT_GE(fd, 0); + + /* + * We're holding a fd open for writing so this needs to fail somewhere + * in the middle and the mount options need to be unchanged. + */ + attr.attr_set = MOUNT_ATTR_RDONLY; + ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), true); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true); + + EXPECT_EQ(close(fd), 0); +} + +TEST_F(mount_setattr, mount_has_writers) +{ + int fd, dfd; + unsigned int old_flags = 0, new_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME, + .attr_clr = MOUNT_ATTR__ATIME, + .propagation = MS_SHARED, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777); + ASSERT_GE(fd, 0); + + /* + * We're holding a fd open to a mount somwhere in the middle so this + * needs to fail somewhere in the middle. After this the mount options + * need to be unchanged. + */ + ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), false); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), false); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), false); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, old_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), false); + + dfd = open("/mnt/A/AA/B", O_DIRECTORY | O_CLOEXEC); + ASSERT_GE(dfd, 0); + EXPECT_EQ(fsync(dfd), 0); + EXPECT_EQ(close(dfd), 0); + + EXPECT_EQ(fsync(fd), 0); + EXPECT_EQ(close(fd), 0); + + /* All writers are gone so this should succeed. */ + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); +} + +TEST_F(mount_setattr, mixed_mount_options) +{ + unsigned int old_flags1 = 0, old_flags2 = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_clr = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME, + .attr_set = MOUNT_ATTR_RELATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags1 = read_mnt_flags("/mnt/B"); + ASSERT_GT(old_flags1, 0); + + old_flags2 = read_mnt_flags("/mnt/B/BB"); + ASSERT_GT(old_flags2, 0); + + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/B", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags = old_flags2; + expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID); + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/B"); + ASSERT_EQ(new_flags, expected_flags); + + expected_flags = old_flags2; + expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID); + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/B/BB"); + ASSERT_EQ(new_flags, expected_flags); +} + +TEST_F(mount_setattr, time_changes) +{ + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = MOUNT_ATTR_STRICTATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME; + attr.attr_clr = MOUNT_ATTR__ATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_set = 0; + attr.attr_clr = MOUNT_ATTR_STRICTATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + attr.attr_clr = MOUNT_ATTR_NOATIME; + ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + attr.attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME; + attr.attr_clr = MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags = old_flags; + expected_flags |= MS_NOATIME; + expected_flags |= MS_NODIRATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_set &= ~MOUNT_ATTR_NOATIME; + attr.attr_set |= MOUNT_ATTR_RELATIME; + attr.attr_clr |= MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_NOATIME; + expected_flags |= MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_set &= ~MOUNT_ATTR_RELATIME; + attr.attr_set |= MOUNT_ATTR_STRICTATIME; + attr.attr_clr |= MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_RELATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_set &= ~MOUNT_ATTR_STRICTATIME; + attr.attr_set |= MOUNT_ATTR_NOATIME; + attr.attr_clr |= MOUNT_ATTR__ATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags |= MS_NOATIME; + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + memset(&attr, 0, sizeof(attr)); + attr.attr_clr = MOUNT_ATTR_NODIRATIME; + ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0); + + expected_flags &= ~MS_NODIRATIME; + + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); +} + +TEST_F(mount_setattr, multi_threaded) +{ + int i, j, nthreads, ret = 0; + unsigned int old_flags = 0, new_flags = 0, expected_flags = 0; + pthread_attr_t pattr; + pthread_t threads[DEFAULT_THREADS]; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + old_flags = read_mnt_flags("/mnt/A"); + ASSERT_GT(old_flags, 0); + + /* Try to change mount options from multiple threads. */ + nthreads = get_nprocs_conf(); + if (nthreads > DEFAULT_THREADS) + nthreads = DEFAULT_THREADS; + + pthread_attr_init(&pattr); + for (i = 0; i < nthreads; i++) + ASSERT_EQ(pthread_create(&threads[i], &pattr, mount_setattr_thread, NULL), 0); + + for (j = 0; j < i; j++) { + void *retptr = NULL; + + EXPECT_EQ(pthread_join(threads[j], &retptr), 0); + + ret += ptr_to_int(retptr); + EXPECT_EQ(ret, 0); + } + pthread_attr_destroy(&pattr); + + ASSERT_EQ(ret, 0); + + expected_flags = old_flags; + expected_flags |= MS_RDONLY; + expected_flags |= MS_NOSUID; + new_flags = read_mnt_flags("/mnt/A"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A"), true); + + new_flags = read_mnt_flags("/mnt/A/AA"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true); + + new_flags = read_mnt_flags("/mnt/A/AA/B/BB"); + ASSERT_EQ(new_flags, expected_flags); + + ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true); +} + +TEST_F(mount_setattr, wrong_user_namespace) +{ + int ret; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + EXPECT_EQ(create_and_enter_userns(), 0); + ret = sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)); + ASSERT_LT(ret, 0); + ASSERT_EQ(errno, EPERM); +} + +TEST_F(mount_setattr, wrong_mount_namespace) +{ + int fd, ret; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_RDONLY, + }; + + if (!mount_setattr_supported()) + SKIP(return, "mount_setattr syscall not supported"); + + fd = open("/mnt/A", O_DIRECTORY | O_CLOEXEC); + ASSERT_GE(fd, 0); + + ASSERT_EQ(unshare(CLONE_NEWNS), 0); + + ret = sys_mount_setattr(fd, "", AT_EMPTY_PATH | AT_RECURSIVE, &attr, sizeof(attr)); + ASSERT_LT(ret, 0); + ASSERT_EQ(errno, EINVAL); +} + +TEST_HARNESS_MAIN -- 2.29.2
next prev parent reply other threads:[~2020-12-04 0:03 UTC|newest] Thread overview: 98+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-12-03 23:56 [PATCH v4 00/40] idmapped mounts Christian Brauner 2020-12-03 23:56 ` Christian Brauner 2020-12-03 23:56 ` [PATCH v4 01/40] namespace: take lock_mount_hash() directly when changing flags Christian Brauner 2020-12-03 23:56 ` Christian Brauner 2020-12-03 23:56 ` [PATCH v4 02/40] mount: make {lock,unlock}_mount_hash() static Christian Brauner 2020-12-03 23:56 ` Christian Brauner 2020-12-03 23:56 ` [PATCH v4 03/40] namespace: only take read lock in do_reconfigure_mnt() Christian Brauner 2020-12-03 23:56 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 04/40] fs: split out functions to hold writers Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-07 17:08 ` Christoph Hellwig 2020-12-07 17:08 ` Christoph Hellwig 2020-12-03 23:57 ` [PATCH v4 05/40] fs: add attr_flags_to_mnt_flags helper Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-07 17:10 ` Christoph Hellwig 2020-12-07 17:10 ` Christoph Hellwig 2020-12-08 10:07 ` Christian Brauner 2020-12-08 10:07 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 06/40] fs: add mount_setattr() Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-07 17:14 ` Christoph Hellwig 2020-12-07 17:14 ` Christoph Hellwig 2020-12-08 10:37 ` Christian Brauner 2020-12-08 10:37 ` Christian Brauner 2020-12-08 15:05 ` Christoph Hellwig 2020-12-08 15:05 ` Christoph Hellwig 2020-12-08 15:22 ` Christian Brauner 2020-12-08 15:22 ` Christian Brauner 2020-12-08 15:26 ` Christian Brauner 2020-12-08 15:26 ` Christian Brauner 2020-12-03 23:57 ` Christian Brauner [this message] 2020-12-03 23:57 ` [PATCH v4 07/40] tests: add mount_setattr() selftests Christian Brauner 2020-12-03 23:57 ` [PATCH v4 08/40] fs: add id translation helpers Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 09/40] mount: attach mappings to mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 10/40] capability: handle idmapped mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 11/40] namei: make permission helpers idmapped mount aware Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 12/40] inode: make init and " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 13/40] attr: handle idmapped mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 14/40] acl: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 15/40] xattr: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 16/40] commoncap: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 17/40] stat: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 18/40] namei: handle idmapped mounts in may_*() helpers Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 19/40] namei: introduce struct renamedata Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 20/40] namei: prepare for idmapped mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 21/40] open: handle idmapped mounts in do_truncate() Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 22/40] open: handle idmapped mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 23/40] af_unix: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 24/40] utimes: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 25/40] fcntl: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 26/40] notify: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 27/40] init: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 28/40] ioctl: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 29/40] would_dump: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 30/40] exec: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 31/40] fs: make helpers idmap mount aware Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 32/40] apparmor: handle idmapped mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 33/40] ima: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 34/40] fat: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 35/40] ext4: support " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 36/40] ecryptfs: do not mount on top of " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 37/40] overlayfs: " Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 38/40] fs: introduce MOUNT_ATTR_IDMAP Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 39/40] tests: extend mount_setattr tests Christian Brauner 2020-12-03 23:57 ` Christian Brauner 2020-12-03 23:57 ` [PATCH v4 40/40] generic/618: add fstests for idmapped mounts Christian Brauner 2020-12-03 23:57 ` Christian Brauner
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