// 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 <fcntl.h> #include <sys/syscall.h> #include <sys/types.h> #include <sys/uio.h> #include <string> #include <vector> #include "gtest/gtest.h" #include "test/syscalls/linux/file_base.h" #include "test/util/file_descriptor.h" #include "test/util/temp_path.h" #include "test/util/test_util.h" namespace gvisor { namespace testing { namespace { #ifndef SYS_pwritev2 #if defined(__x86_64__) #define SYS_pwritev2 328 #else #error "Unknown architecture" #endif #endif // SYS_pwrite2 #ifndef RWF_HIPRI #define RWF_HIPRI 0x1 #endif // RWF_HIPRI #ifndef RWF_DSYNC #define RWF_DSYNC 0x2 #endif // RWF_DSYNC #ifndef RWF_SYNC #define RWF_SYNC 0x4 #endif // RWF_SYNC constexpr int kBufSize = 1024; void SetContent(std::vector<char>& content) { for (uint i = 0; i < content.size(); i++) { content[i] = static_cast<char>((i % 10) + '0'); } } ssize_t pwritev2(unsigned long fd, const struct iovec* iov, unsigned long iovcnt, off_t offset, unsigned long flags) { // syscall on pwritev2 does some weird things (see man syscall and search // pwritev2), so we insert a 0 to word align the flags argument on native. return syscall(SYS_pwritev2, fd, iov, iovcnt, offset, 0, flags); } // This test is the base case where we call pwritev (no offset, no flags). TEST(Writev2Test, TestBaseCall) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), "", TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); std::vector<char> content(kBufSize); SetContent(content); struct iovec iov[2]; iov[0].iov_base = content.data(); iov[0].iov_len = content.size() / 2; iov[1].iov_base = static_cast<char*>(iov[0].iov_base) + (content.size() / 2); iov[1].iov_len = content.size() / 2; ASSERT_THAT(pwritev2(fd.get(), iov, /*iovcnt=*/2, /*offset=*/0, /*flags=*/0), SyscallSucceedsWithValue(kBufSize)); std::vector<char> buf(kBufSize); EXPECT_THAT(read(fd.get(), buf.data(), kBufSize), SyscallSucceedsWithValue(kBufSize)); EXPECT_EQ(content, buf); } // This test is where we call pwritev2 with a positive offset and no flags. TEST(Pwritev2Test, TestValidPositiveOffset) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); std::string prefix(kBufSize, '0'); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), prefix, TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); std::vector<char> content(kBufSize); SetContent(content); struct iovec iov; iov.iov_base = content.data(); iov.iov_len = content.size(); ASSERT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/prefix.size(), /*flags=*/0), SyscallSucceedsWithValue(content.size())); std::vector<char> buf(prefix.size() + content.size()); EXPECT_THAT(read(fd.get(), buf.data(), buf.size()), SyscallSucceedsWithValue(buf.size())); std::vector<char> want(prefix.begin(), prefix.end()); want.insert(want.end(), content.begin(), content.end()); EXPECT_EQ(want, buf); } // This test is the base case where we call writev by using -1 as the offset. // The write should use the file offset, so the test increments the file offset // prior to call pwritev2. TEST(Pwritev2Test, TestNegativeOneOffset) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const std::string prefix = "00"; const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), prefix.data(), TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); ASSERT_THAT(lseek(fd.get(), prefix.size(), SEEK_SET), SyscallSucceedsWithValue(prefix.size())); std::vector<char> content(kBufSize); SetContent(content); struct iovec iov; iov.iov_base = content.data(); iov.iov_len = content.size(); ASSERT_THAT(pwritev2(fd.get(), &iov, /*iovcnt*/ 1, /*offset=*/static_cast<off_t>(-1), /*flags=*/0), SyscallSucceedsWithValue(content.size())); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(prefix.size() + content.size())); std::vector<char> buf(prefix.size() + content.size()); EXPECT_THAT(pread(fd.get(), buf.data(), buf.size(), /*offset=*/0), SyscallSucceedsWithValue(buf.size())); std::vector<char> want(prefix.begin(), prefix.end()); want.insert(want.end(), content.begin(), content.end()); EXPECT_EQ(want, buf); } // pwritev2 requires if the RWF_HIPRI flag is passed, the fd must be opened with // O_DIRECT. This test implements a correct call with the RWF_HIPRI flag. TEST(Pwritev2Test, TestCallWithRWF_HIPRI) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), "", TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); std::vector<char> content(kBufSize); SetContent(content); struct iovec iov; iov.iov_base = content.data(); iov.iov_len = content.size(); EXPECT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/0, /*flags=*/RWF_HIPRI), SyscallSucceedsWithValue(kBufSize)); std::vector<char> buf(content.size()); EXPECT_THAT(read(fd.get(), buf.data(), buf.size()), SyscallSucceedsWithValue(buf.size())); EXPECT_EQ(buf, content); } // This test checks that pwritev2 can be called with valid flags TEST(Pwritev2Test, TestCallWithValidFlags) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), "", TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); std::vector<char> content(kBufSize, '0'); struct iovec iov; iov.iov_base = content.data(); iov.iov_len = content.size(); EXPECT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/0, /*flags=*/RWF_DSYNC), SyscallSucceedsWithValue(kBufSize)); std::vector<char> buf(content.size()); EXPECT_THAT(read(fd.get(), buf.data(), buf.size()), SyscallSucceedsWithValue(buf.size())); EXPECT_EQ(buf, content); SetContent(content); EXPECT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/0, /*flags=*/0x4), SyscallSucceedsWithValue(kBufSize)); ASSERT_THAT(lseek(fd.get(), 0, SEEK_CUR), SyscallSucceedsWithValue(content.size())); EXPECT_THAT(pread(fd.get(), buf.data(), buf.size(), /*offset=*/0), SyscallSucceedsWithValue(buf.size())); EXPECT_EQ(buf, content); } // This test calls pwritev2 with a bad file descriptor. TEST(Writev2Test, TestBadFile) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); ASSERT_THAT(pwritev2(/*fd=*/-1, /*iov=*/nullptr, /*iovcnt=*/0, /*offset=*/0, /*flags=*/0), SyscallFailsWithErrno(EBADF)); } // This test calls pwrite2 with an invalid offset. TEST(Pwritev2Test, TestInvalidOffset) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), "", TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR)); char buf[16]; struct iovec iov; iov.iov_base = buf; iov.iov_len = sizeof(buf); EXPECT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/static_cast<off_t>(-8), /*flags=*/0), SyscallFailsWithErrno(EINVAL)); } TEST(Pwritev2Test, TestUnseekableFileValid) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); int pipe_fds[2]; ASSERT_THAT(pipe(pipe_fds), SyscallSucceeds()); std::vector<char> content(32, '0'); SetContent(content); struct iovec iov; iov.iov_base = content.data(); iov.iov_len = content.size(); EXPECT_THAT(pwritev2(pipe_fds[1], &iov, /*iovcnt=*/1, /*offset=*/static_cast<off_t>(-1), /*flags=*/0), SyscallSucceedsWithValue(content.size())); std::vector<char> buf(content.size()); EXPECT_THAT(read(pipe_fds[0], buf.data(), buf.size()), SyscallSucceedsWithValue(buf.size())); EXPECT_EQ(content, buf); EXPECT_THAT(close(pipe_fds[0]), SyscallSucceeds()); EXPECT_THAT(close(pipe_fds[1]), SyscallSucceeds()); } // Calling pwritev2 with a non-negative offset calls pwritev. Calling pwritev // with an unseekable file is not allowed. A pipe is used for an unseekable // file. TEST(Pwritev2Test, TestUnseekableFileInValid) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); int pipe_fds[2]; char buf[16]; struct iovec iov; iov.iov_base = buf; iov.iov_len = sizeof(buf); ASSERT_THAT(pipe(pipe_fds), SyscallSucceeds()); EXPECT_THAT(pwritev2(pipe_fds[1], &iov, /*iovcnt=*/1, /*offset=*/2, /*flags=*/0), SyscallFailsWithErrno(ESPIPE)); EXPECT_THAT(close(pipe_fds[0]), SyscallSucceeds()); EXPECT_THAT(close(pipe_fds[1]), SyscallSucceeds()); } TEST(Pwritev2Test, TestReadOnlyFile) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), "", TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDONLY)); char buf[16]; struct iovec iov; iov.iov_base = buf; iov.iov_len = sizeof(buf); EXPECT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/0, /*flags=*/0), SyscallFailsWithErrno(EBADF)); } // This test calls pwritev2 with an invalid flag. TEST(Pwritev2Test, TestInvalidFlag) { SKIP_IF(pwritev2(-1, nullptr, 0, 0, 0) < 0 && errno == ENOSYS); const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFileWith( GetAbsoluteTestTmpdir(), "", TempPath::kDefaultFileMode)); const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Open(file.path(), O_RDWR | O_DIRECT)); char buf[16]; struct iovec iov; iov.iov_base = buf; iov.iov_len = sizeof(buf); EXPECT_THAT(pwritev2(fd.get(), &iov, /*iovcnt=*/1, /*offset=*/0, /*flags=*/0xF0), SyscallFailsWithErrno(EOPNOTSUPP)); } } // namespace } // namespace testing } // namespace gvisor