// 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 <stdlib.h> #include <sys/stat.h> #include <sys/types.h> #include <unistd.h> #include "gtest/gtest.h" #include "test/util/file_descriptor.h" #include "test/util/temp_path.h" #include "test/util/test_util.h" namespace gvisor { namespace testing { namespace { TEST(LseekTest, InvalidWhence) { const std::string kFileData = "hello world\n"; const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644)); ASSERT_THAT(lseek(fd.get(), 0, -1), SyscallFailsWithErrno(EINVAL)); } TEST(LseekTest, NegativeOffset) { const std::string kFileData = "hello world\n"; const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644)); EXPECT_THAT(lseek(fd.get(), -(kFileData.length() + 1), SEEK_CUR), SyscallFailsWithErrno(EINVAL)); } // A 32-bit off_t is not large enough to represent an offset larger than // maximum file size on standard file systems, so it isn't possible to cause // overflow. #ifdef __x86_64__ TEST(LseekTest, Overflow) { // HA! Classic Linux. We really should have an EOVERFLOW // here, since we're seeking to something that cannot be // represented.. but instead we are given an EINVAL. const std::string kFileData = "hello world\n"; const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644)); EXPECT_THAT(lseek(fd.get(), 0x7fffffffffffffff, SEEK_END), SyscallFailsWithErrno(EINVAL)); } #endif TEST(LseekTest, Set) { const std::string kFileData = "hello world\n"; const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644)); char buf = '\0'; EXPECT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceedsWithValue(0)); ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1)); EXPECT_EQ(buf, kFileData.c_str()[0]); EXPECT_THAT(lseek(fd.get(), 6, SEEK_SET), SyscallSucceedsWithValue(6)); ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1)); EXPECT_EQ(buf, kFileData.c_str()[6]); } TEST(LseekTest, Cur) { const std::string kFileData = "hello world\n"; const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644)); char buf = '\0'; EXPECT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceedsWithValue(0)); ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1)); EXPECT_EQ(buf, kFileData.c_str()[0]); EXPECT_THAT(lseek(fd.get(), 3, SEEK_CUR), SyscallSucceedsWithValue(4)); ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1)); EXPECT_EQ(buf, kFileData.c_str()[4]); } TEST(LseekTest, End) { const std::string kFileData = "hello world\n"; const TempPath path = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), kFileData, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(path.path(), O_RDWR, 0644)); char buf = '\0'; EXPECT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceedsWithValue(0)); ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1)); EXPECT_EQ(buf, kFileData.c_str()[0]); EXPECT_THAT(lseek(fd.get(), -2, SEEK_END), SyscallSucceedsWithValue(10)); ASSERT_THAT(read(fd.get(), &buf, 1), SyscallSucceedsWithValue(1)); EXPECT_EQ(buf, kFileData.c_str()[kFileData.length() - 2]); } TEST(LseekTest, InvalidFD) { EXPECT_THAT(lseek(-1, 0, SEEK_SET), SyscallFailsWithErrno(EBADF)); } TEST(LseekTest, DirCurEnd) { const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open("/tmp", O_RDONLY)); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0)); } TEST(LseekTest, ProcDir) { const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/self", O_RDONLY)); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds()); ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallSucceeds()); } TEST(LseekTest, ProcFile) { const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/meminfo", O_RDONLY)); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds()); ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallFailsWithErrno(EINVAL)); } TEST(LseekTest, SysDir) { const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open("/sys/devices", O_RDONLY)); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds()); ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), SyscallSucceeds()); } TEST(LseekTest, SeekCurrentDir) { // From include/linux/fs.h. constexpr loff_t MAX_LFS_FILESIZE = 0x7fffffffffffffff; char* dir = get_current_dir_name(); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(dir, O_RDONLY)); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceeds()); ASSERT_THAT(lseek(fd.get(), 0, SEEK_END), // Some filesystems (like ext4) allow lseek(SEEK_END) on a // directory and return MAX_LFS_FILESIZE, others return EINVAL. AnyOf(SyscallSucceedsWithValue(MAX_LFS_FILESIZE), SyscallFailsWithErrno(EINVAL))); free(dir); } TEST(LseekTest, ProcStatTwice) { const FileDescriptor fd1 = ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/stat", O_RDONLY)); const FileDescriptor fd2 = ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/stat", O_RDONLY)); ASSERT_THAT(lseek(fd1.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0)); ASSERT_THAT(lseek(fd1.get(), 0, SEEK_END), SyscallFailsWithErrno(EINVAL)); ASSERT_THAT(lseek(fd1.get(), 1000, SEEK_CUR), SyscallSucceeds()); // Check that just because we moved fd1, fd2 doesn't move. ASSERT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0)); const FileDescriptor fd3 = ASSERT_NO_ERRNO_AND_VALUE(Open("/proc/stat", O_RDONLY)); ASSERT_THAT(lseek(fd3.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0)); } TEST(LseekTest, EtcPasswdDup) { const FileDescriptor fd1 = ASSERT_NO_ERRNO_AND_VALUE(Open("/etc/passwd", O_RDONLY)); const FileDescriptor fd2 = ASSERT_NO_ERRNO_AND_VALUE(fd1.Dup()); ASSERT_THAT(lseek(fd1.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0)); ASSERT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(0)); ASSERT_THAT(lseek(fd1.get(), 1000, SEEK_CUR), SyscallSucceeds()); // Check that just because we moved fd1, fd2 doesn't move. ASSERT_THAT(lseek(fd2.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(1000)); const FileDescriptor fd3 = ASSERT_NO_ERRNO_AND_VALUE(fd1.Dup()); ASSERT_THAT(lseek(fd3.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(1000)); } // TODO(magi): Add tests where we have donated in sockets. } // namespace } // namespace testing } // namespace gvisor