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Diffstat (limited to 'test/syscalls/linux/mount.cc')
| -rw-r--r-- | test/syscalls/linux/mount.cc | 419 |
1 files changed, 0 insertions, 419 deletions
diff --git a/test/syscalls/linux/mount.cc b/test/syscalls/linux/mount.cc deleted file mode 100644 index e2a41d172..000000000 --- a/test/syscalls/linux/mount.cc +++ /dev/null @@ -1,419 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -#include <errno.h> -#include <fcntl.h> -#include <stdio.h> -#include <sys/mount.h> -#include <sys/stat.h> -#include <unistd.h> - -#include <functional> -#include <memory> -#include <string> -#include <vector> - -#include "gmock/gmock.h" -#include "gtest/gtest.h" -#include "absl/strings/str_split.h" -#include "absl/strings/string_view.h" -#include "absl/time/time.h" -#include "test/util/capability_util.h" -#include "test/util/file_descriptor.h" -#include "test/util/fs_util.h" -#include "test/util/mount_util.h" -#include "test/util/multiprocess_util.h" -#include "test/util/posix_error.h" -#include "test/util/save_util.h" -#include "test/util/temp_path.h" -#include "test/util/test_util.h" -#include "test/util/thread_util.h" - -namespace gvisor { -namespace testing { - -namespace { - -using ::testing::AnyOf; -using ::testing::Contains; -using ::testing::Pair; - -TEST(MountTest, MountBadFilesystem) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - // Linux expects a valid target before it checks the file system name. - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - EXPECT_THAT(mount("", dir.path().c_str(), "foobar", 0, ""), - SyscallFailsWithErrno(ENODEV)); -} - -TEST(MountTest, MountInvalidTarget) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = NewTempAbsPath(); - EXPECT_THAT(mount("", dir.c_str(), "tmpfs", 0, ""), - SyscallFailsWithErrno(ENOENT)); -} - -TEST(MountTest, MountPermDenied) { - // Clear CAP_SYS_ADMIN. - AutoCapability cap(CAP_SYS_ADMIN, false); - - // Linux expects a valid target before checking capability. - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - EXPECT_THAT(mount("", dir.path().c_str(), "", 0, ""), - SyscallFailsWithErrno(EPERM)); -} - -TEST(MountTest, UmountPermDenied) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount = - ASSERT_NO_ERRNO_AND_VALUE(Mount("", dir.path(), "tmpfs", 0, "", 0)); - - // Drop privileges in another thread, so we can still unmount the mounted - // directory. - ScopedThread([&]() { - EXPECT_NO_ERRNO(SetCapability(CAP_SYS_ADMIN, false)); - EXPECT_THAT(umount(dir.path().c_str()), SyscallFailsWithErrno(EPERM)); - }); -} - -TEST(MountTest, MountOverBusy) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const fd = ASSERT_NO_ERRNO_AND_VALUE( - Open(JoinPath(dir.path(), "foo"), O_CREAT | O_RDWR, 0777)); - - // Should be able to mount over a busy directory. - ASSERT_NO_ERRNO_AND_VALUE(Mount("", dir.path(), "tmpfs", 0, "", 0)); -} - -TEST(MountTest, OpenFileBusy) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", 0, "mode=0700", 0)); - auto const fd = ASSERT_NO_ERRNO_AND_VALUE( - Open(JoinPath(dir.path(), "foo"), O_CREAT | O_RDWR, 0777)); - - // An open file should prevent unmounting. - EXPECT_THAT(umount(dir.path().c_str()), SyscallFailsWithErrno(EBUSY)); -} - -TEST(MountTest, UmountNoFollow) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - - auto const mountPoint = NewTempAbsPathInDir(dir.path()); - ASSERT_THAT(mkdir(mountPoint.c_str(), 0777), SyscallSucceeds()); - - // Create a symlink in dir which will point to the actual mountpoint. - const std::string symlinkInDir = NewTempAbsPathInDir(dir.path()); - EXPECT_THAT(symlink(mountPoint.c_str(), symlinkInDir.c_str()), - SyscallSucceeds()); - - // Create a symlink to the dir. - const std::string symlinkToDir = NewTempAbsPath(); - EXPECT_THAT(symlink(dir.path().c_str(), symlinkToDir.c_str()), - SyscallSucceeds()); - - // Should fail with ELOOP when UMOUNT_NOFOLLOW is specified and the last - // component is a symlink. - auto mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", mountPoint, "tmpfs", 0, "mode=0700", 0)); - EXPECT_THAT(umount2(symlinkInDir.c_str(), UMOUNT_NOFOLLOW), - SyscallFailsWithErrno(EINVAL)); - EXPECT_THAT(unlink(symlinkInDir.c_str()), SyscallSucceeds()); - - // UMOUNT_NOFOLLOW should only apply to the last path component. A symlink in - // non-last path component should be just fine. - EXPECT_THAT(umount2(JoinPath(symlinkToDir, Basename(mountPoint)).c_str(), - UMOUNT_NOFOLLOW), - SyscallSucceeds()); - mount.Release(); -} - -TEST(MountTest, UmountDetach) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - // structure: - // - // dir (mount point) - // subdir - // file - // - // We show that we can walk around in the mount after detach-unmount dir. - // - // We show that even though dir is unreachable from outside the mount, we can - // still reach dir's (former) parent! - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - - const struct stat before = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - auto mount = - ASSERT_NO_ERRNO_AND_VALUE(Mount("", dir.path(), "tmpfs", 0, "mode=0700", - /* umountflags= */ MNT_DETACH)); - const struct stat after = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - EXPECT_FALSE(before.st_dev == after.st_dev && before.st_ino == after.st_ino) - << "mount point has device number " << before.st_dev - << " and inode number " << before.st_ino << " before and after mount"; - - // Create files in the new mount. - constexpr char kContents[] = "no no no"; - auto const subdir = - ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDirIn(dir.path())); - auto const file = ASSERT_NO_ERRNO_AND_VALUE( - TempPath::CreateFileWith(dir.path(), kContents, 0777)); - - auto const dir_fd = - ASSERT_NO_ERRNO_AND_VALUE(Open(subdir.path(), O_RDONLY | O_DIRECTORY)); - auto const fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDONLY)); - - // Unmount the tmpfs. - mount.Release()(); - - // Inode numbers for gofer-accessed files may change across save/restore. - // - // For overlayfs, if xino option is not enabled and if all overlayfs layers do - // not belong to the same filesystem then "the value of st_ino for directory - // objects may not be persistent and could change even while the overlay - // filesystem is mounted." -- Documentation/filesystems/overlayfs.txt - if (!IsRunningWithSaveRestore() && - !ASSERT_NO_ERRNO_AND_VALUE(IsOverlayfs(dir.path()))) { - const struct stat after2 = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - EXPECT_EQ(before.st_ino, after2.st_ino); - } - - // Can still read file after unmounting. - std::vector<char> buf(sizeof(kContents)); - EXPECT_THAT(ReadFd(fd.get(), buf.data(), buf.size()), SyscallSucceeds()); - - // Walk to dir. - auto const mounted_dir = ASSERT_NO_ERRNO_AND_VALUE( - OpenAt(dir_fd.get(), "..", O_DIRECTORY | O_RDONLY)); - // Walk to dir/file. - auto const fd_again = ASSERT_NO_ERRNO_AND_VALUE( - OpenAt(mounted_dir.get(), std::string(Basename(file.path())), O_RDONLY)); - - std::vector<char> buf2(sizeof(kContents)); - EXPECT_THAT(ReadFd(fd_again.get(), buf2.data(), buf2.size()), - SyscallSucceeds()); - EXPECT_EQ(buf, buf2); - - // Walking outside the unmounted realm should still work, too! - auto const dir_parent = ASSERT_NO_ERRNO_AND_VALUE( - OpenAt(mounted_dir.get(), "..", O_DIRECTORY | O_RDONLY)); -} - -TEST(MountTest, ActiveSubmountBusy) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount1 = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", 0, "mode=0700", 0)); - - auto const dir2 = - ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDirIn(dir.path())); - auto const mount2 = - ASSERT_NO_ERRNO_AND_VALUE(Mount("", dir2.path(), "tmpfs", 0, "", 0)); - - // Since dir now has an active submount, should not be able to unmount. - EXPECT_THAT(umount(dir.path().c_str()), SyscallFailsWithErrno(EBUSY)); -} - -TEST(MountTest, MountTmpfs) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - - // NOTE(b/129868551): Inode IDs are only stable across S/R if we have an open - // FD for that inode. Since we are going to compare inode IDs below, get a - // FileDescriptor for this directory here, which will be closed automatically - // at the end of the test. - auto const fd = - ASSERT_NO_ERRNO_AND_VALUE(Open(dir.path(), O_DIRECTORY, O_RDONLY)); - - const struct stat before = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - - { - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", 0, "mode=0700", 0)); - - const struct stat s = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - EXPECT_EQ(s.st_mode, S_IFDIR | 0700); - EXPECT_FALSE(before.st_dev == s.st_dev && before.st_ino == s.st_ino) - << "mount point has device number " << before.st_dev - << " and inode number " << before.st_ino << " before and after mount"; - - EXPECT_NO_ERRNO(Open(JoinPath(dir.path(), "foo"), O_CREAT | O_RDWR, 0777)); - } - - // Now that dir is unmounted again, we should have the old inode back. - // - // Inode numbers for gofer-accessed files may change across save/restore. - // - // For overlayfs, if xino option is not enabled and if all overlayfs layers do - // not belong to the same filesystem then "the value of st_ino for directory - // objects may not be persistent and could change even while the overlay - // filesystem is mounted." -- Documentation/filesystems/overlayfs.txt - if (!IsRunningWithSaveRestore() && - !ASSERT_NO_ERRNO_AND_VALUE(IsOverlayfs(dir.path()))) { - const struct stat after = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - EXPECT_EQ(before.st_ino, after.st_ino); - } -} - -TEST(MountTest, MountTmpfsMagicValIgnored) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", MS_MGC_VAL, "mode=0700", 0)); -} - -// Passing nullptr to data is equivalent to "". -TEST(MountTest, NullData) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - - EXPECT_THAT(mount("", dir.path().c_str(), "tmpfs", 0, nullptr), - SyscallSucceeds()); - EXPECT_THAT(umount2(dir.path().c_str(), 0), SyscallSucceeds()); -} - -TEST(MountTest, MountReadonly) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", MS_RDONLY, "mode=0777", 0)); - - const struct stat s = ASSERT_NO_ERRNO_AND_VALUE(Stat(dir.path())); - EXPECT_EQ(s.st_mode, S_IFDIR | 0777); - - std::string const filename = JoinPath(dir.path(), "foo"); - EXPECT_THAT(open(filename.c_str(), O_RDWR | O_CREAT, 0777), - SyscallFailsWithErrno(EROFS)); -} - -PosixErrorOr<absl::Time> ATime(absl::string_view file) { - struct stat s = {}; - if (stat(std::string(file).c_str(), &s) == -1) { - return PosixError(errno, "stat failed"); - } - return absl::TimeFromTimespec(s.st_atim); -} - -TEST(MountTest, MountNoAtime) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", MS_NOATIME, "mode=0777", 0)); - - std::string const contents = "No no no, don't follow the instructions!"; - auto const file = ASSERT_NO_ERRNO_AND_VALUE( - TempPath::CreateFileWith(dir.path(), contents, 0777)); - - absl::Time const before = ASSERT_NO_ERRNO_AND_VALUE(ATime(file.path())); - - // Reading from the file should change the atime, but the MS_NOATIME flag - // should prevent that. - auto const fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); - char buf[100]; - int read_n; - ASSERT_THAT(read_n = read(fd.get(), buf, sizeof(buf)), SyscallSucceeds()); - EXPECT_EQ(std::string(buf, read_n), contents); - - absl::Time const after = ASSERT_NO_ERRNO_AND_VALUE(ATime(file.path())); - - // Expect that atime hasn't changed. - EXPECT_EQ(before, after); -} - -TEST(MountTest, MountNoExec) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", MS_NOEXEC, "mode=0777", 0)); - - std::string const contents = "No no no, don't follow the instructions!"; - auto const file = ASSERT_NO_ERRNO_AND_VALUE( - TempPath::CreateFileWith(dir.path(), contents, 0777)); - - int execve_errno; - ASSERT_NO_ERRNO_AND_VALUE( - ForkAndExec(file.path(), {}, {}, nullptr, &execve_errno)); - EXPECT_EQ(execve_errno, EACCES); -} - -TEST(MountTest, RenameRemoveMountPoint) { - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir_parent = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const dir = - ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDirIn(dir_parent.path())); - auto const new_dir = NewTempAbsPath(); - - auto const mount = - ASSERT_NO_ERRNO_AND_VALUE(Mount("", dir.path(), "tmpfs", 0, "", 0)); - - ASSERT_THAT(rename(dir.path().c_str(), new_dir.c_str()), - SyscallFailsWithErrno(EBUSY)); - - ASSERT_THAT(rmdir(dir.path().c_str()), SyscallFailsWithErrno(EBUSY)); -} - -TEST(MountTest, MountInfo) { - SKIP_IF(IsRunningWithVFS1()); - SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); - - auto const dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); - auto const mount = ASSERT_NO_ERRNO_AND_VALUE( - Mount("", dir.path(), "tmpfs", MS_NOEXEC, "mode=0123", 0)); - const std::vector<ProcMountsEntry> mounts = - ASSERT_NO_ERRNO_AND_VALUE(ProcSelfMountsEntries()); - for (const auto& e : mounts) { - if (e.mount_point == dir.path()) { - EXPECT_EQ(e.fstype, "tmpfs"); - auto mopts = ParseMountOptions(e.mount_opts); - EXPECT_THAT(mopts, AnyOf(Contains(Pair("mode", "0123")), - Contains(Pair("mode", "123")))); - } - } - - const std::vector<ProcMountInfoEntry> mountinfo = - ASSERT_NO_ERRNO_AND_VALUE(ProcSelfMountInfoEntries()); - - for (auto const& e : mountinfo) { - if (e.mount_point == dir.path()) { - EXPECT_EQ(e.fstype, "tmpfs"); - auto mopts = ParseMountOptions(e.super_opts); - EXPECT_THAT(mopts, AnyOf(Contains(Pair("mode", "0123")), - Contains(Pair("mode", "123")))); - } - } -} - -} // namespace - -} // namespace testing -} // namespace gvisor |