Merge branch 'master' into ip-forwarding

- Merges aleksej-paschenko's with HEAD
- Adds vfs2 support for ip_forward

1 files changed, 610 insertions, 0 deletions

diff --git a/test/syscalls/linux/xattr.cc b/test/syscalls/linux/xattr.cc
new file mode 100644
index 000000000..cbcf08451
--- /dev/null
+++ b/test/syscalls/linux/xattr.cc
@@ -0,0 +1,610 @@
+// Copyright 2019 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 <limits.h>
+#include <sys/types.h>
+#include <sys/xattr.h>
+#include <unistd.h>
+
+#include <string>
+#include <vector>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "absl/container/flat_hash_set.h"
+#include "test/syscalls/linux/file_base.h"
+#include "test/util/capability_util.h"
+#include "test/util/file_descriptor.h"
+#include "test/util/posix_error.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+class XattrTest : public FileTest {};
+
+TEST_F(XattrTest, XattrNonexistentFile) {
+  const char* path = "/does/not/exist";
+  const char* name = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(ENOENT));
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENOENT));
+  EXPECT_THAT(listxattr(path, nullptr, 0), SyscallFailsWithErrno(ENOENT));
+  EXPECT_THAT(removexattr(path, name), SyscallFailsWithErrno(ENOENT));
+}
+
+TEST_F(XattrTest, XattrNullName) {
+  const char* path = test_file_name_.c_str();
+
+  EXPECT_THAT(setxattr(path, nullptr, nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(EFAULT));
+  EXPECT_THAT(getxattr(path, nullptr, nullptr, 0),
+              SyscallFailsWithErrno(EFAULT));
+  EXPECT_THAT(removexattr(path, nullptr), SyscallFailsWithErrno(EFAULT));
+}
+
+TEST_F(XattrTest, XattrEmptyName) {
+  const char* path = test_file_name_.c_str();
+
+  EXPECT_THAT(setxattr(path, "", nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(ERANGE));
+  EXPECT_THAT(getxattr(path, "", nullptr, 0), SyscallFailsWithErrno(ERANGE));
+  EXPECT_THAT(removexattr(path, ""), SyscallFailsWithErrno(ERANGE));
+}
+
+TEST_F(XattrTest, XattrLargeName) {
+  const char* path = test_file_name_.c_str();
+  std::string name = "user.";
+  name += std::string(XATTR_NAME_MAX - name.length(), 'a');
+
+  if (!IsRunningOnGvisor()) {
+    // In gVisor, access to xattrs is controlled with an explicit list of
+    // allowed names. This name isn't going to be configured to allow access, so
+    // don't test it.
+    EXPECT_THAT(setxattr(path, name.c_str(), nullptr, 0, /*flags=*/0),
+                SyscallSucceeds());
+    EXPECT_THAT(getxattr(path, name.c_str(), nullptr, 0),
+                SyscallSucceedsWithValue(0));
+  }
+
+  name += "a";
+  EXPECT_THAT(setxattr(path, name.c_str(), nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(ERANGE));
+  EXPECT_THAT(getxattr(path, name.c_str(), nullptr, 0),
+              SyscallFailsWithErrno(ERANGE));
+  EXPECT_THAT(removexattr(path, name.c_str()), SyscallFailsWithErrno(ERANGE));
+}
+
+TEST_F(XattrTest, XattrInvalidPrefix) {
+  const char* path = test_file_name_.c_str();
+  std::string name(XATTR_NAME_MAX, 'a');
+  EXPECT_THAT(setxattr(path, name.c_str(), nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(EOPNOTSUPP));
+  EXPECT_THAT(getxattr(path, name.c_str(), nullptr, 0),
+              SyscallFailsWithErrno(EOPNOTSUPP));
+  EXPECT_THAT(removexattr(path, name.c_str()),
+              SyscallFailsWithErrno(EOPNOTSUPP));
+}
+
+// Do not allow save/restore cycles after making the test file read-only, as
+// the restore will fail to open it with r/w permissions.
+TEST_F(XattrTest, XattrReadOnly_NoRandomSave) {
+  // Drop capabilities that allow us to override file and directory permissions.
+  ASSERT_NO_ERRNO(SetCapability(CAP_DAC_OVERRIDE, false));
+  ASSERT_NO_ERRNO(SetCapability(CAP_DAC_READ_SEARCH, false));
+
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  size_t size = sizeof(val);
+
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0), SyscallSucceeds());
+
+  DisableSave ds;
+  ASSERT_NO_ERRNO(testing::Chmod(test_file_name_, S_IRUSR));
+
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0),
+              SyscallFailsWithErrno(EACCES));
+  EXPECT_THAT(removexattr(path, name), SyscallFailsWithErrno(EACCES));
+
+  char buf = '-';
+  EXPECT_THAT(getxattr(path, name, &buf, size), SyscallSucceedsWithValue(size));
+  EXPECT_EQ(buf, val);
+
+  char list[sizeof(name)];
+  EXPECT_THAT(listxattr(path, list, sizeof(list)),
+              SyscallSucceedsWithValue(sizeof(name)));
+  EXPECT_STREQ(list, name);
+}
+
+// Do not allow save/restore cycles after making the test file write-only, as
+// the restore will fail to open it with r/w permissions.
+TEST_F(XattrTest, XattrWriteOnly_NoRandomSave) {
+  // Drop capabilities that allow us to override file and directory permissions.
+  ASSERT_NO_ERRNO(SetCapability(CAP_DAC_OVERRIDE, false));
+  ASSERT_NO_ERRNO(SetCapability(CAP_DAC_READ_SEARCH, false));
+
+  DisableSave ds;
+  ASSERT_NO_ERRNO(testing::Chmod(test_file_name_, S_IWUSR));
+
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  size_t size = sizeof(val);
+
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0), SyscallSucceeds());
+
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(EACCES));
+
+  // listxattr will succeed even without read permissions.
+  char list[sizeof(name)];
+  EXPECT_THAT(listxattr(path, list, sizeof(list)),
+              SyscallSucceedsWithValue(sizeof(name)));
+  EXPECT_STREQ(list, name);
+
+  EXPECT_THAT(removexattr(path, name), SyscallSucceeds());
+}
+
+TEST_F(XattrTest, XattrTrustedWithNonadmin) {
+  // TODO(b/148380782): Support setxattr and getxattr with "trusted" prefix.
+  SKIP_IF(IsRunningOnGvisor());
+  SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN)));
+
+  const char* path = test_file_name_.c_str();
+  const char name[] = "trusted.abc";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(EPERM));
+  EXPECT_THAT(removexattr(path, name), SyscallFailsWithErrno(EPERM));
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENODATA));
+}
+
+TEST_F(XattrTest, XattrOnDirectory) {
+  TempPath dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(dir.path().c_str(), name, nullptr, 0, /*flags=*/0),
+              SyscallSucceeds());
+  EXPECT_THAT(getxattr(dir.path().c_str(), name, nullptr, 0),
+              SyscallSucceedsWithValue(0));
+
+  char list[sizeof(name)];
+  EXPECT_THAT(listxattr(dir.path().c_str(), list, sizeof(list)),
+              SyscallSucceedsWithValue(sizeof(name)));
+  EXPECT_STREQ(list, name);
+
+  EXPECT_THAT(removexattr(dir.path().c_str(), name), SyscallSucceeds());
+}
+
+TEST_F(XattrTest, XattrOnSymlink) {
+  TempPath dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  TempPath link = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateSymlinkTo(dir.path(), test_file_name_));
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(link.path().c_str(), name, nullptr, 0, /*flags=*/0),
+              SyscallSucceeds());
+  EXPECT_THAT(getxattr(link.path().c_str(), name, nullptr, 0),
+              SyscallSucceedsWithValue(0));
+
+  char list[sizeof(name)];
+  EXPECT_THAT(listxattr(link.path().c_str(), list, sizeof(list)),
+              SyscallSucceedsWithValue(sizeof(name)));
+  EXPECT_STREQ(list, name);
+
+  EXPECT_THAT(removexattr(link.path().c_str(), name), SyscallSucceeds());
+}
+
+TEST_F(XattrTest, XattrOnInvalidFileTypes) {
+  const char name[] = "user.test";
+
+  char char_device[] = "/dev/zero";
+  EXPECT_THAT(setxattr(char_device, name, nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(EPERM));
+  EXPECT_THAT(getxattr(char_device, name, nullptr, 0),
+              SyscallFailsWithErrno(ENODATA));
+  EXPECT_THAT(listxattr(char_device, nullptr, 0), SyscallSucceedsWithValue(0));
+
+  // Use tmpfs, where creation of named pipes is supported.
+  const std::string fifo = NewTempAbsPathInDir("/dev/shm");
+  const char* path = fifo.c_str();
+  EXPECT_THAT(mknod(path, S_IFIFO | S_IRUSR | S_IWUSR, 0), SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0),
+              SyscallFailsWithErrno(EPERM));
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENODATA));
+  EXPECT_THAT(listxattr(path, nullptr, 0), SyscallSucceedsWithValue(0));
+  EXPECT_THAT(removexattr(path, name), SyscallFailsWithErrno(EPERM));
+}
+
+TEST_F(XattrTest, SetxattrSizeSmallerThanValue) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  std::vector<char> val = {'a', 'a'};
+  size_t size = 1;
+  EXPECT_THAT(setxattr(path, name, val.data(), size, /*flags=*/0),
+              SyscallSucceeds());
+
+  std::vector<char> buf = {'-', '-'};
+  std::vector<char> expected_buf = {'a', '-'};
+  EXPECT_THAT(getxattr(path, name, buf.data(), buf.size()),
+              SyscallSucceedsWithValue(size));
+  EXPECT_EQ(buf, expected_buf);
+}
+
+TEST_F(XattrTest, SetxattrZeroSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  EXPECT_THAT(setxattr(path, name, &val, 0, /*flags=*/0), SyscallSucceeds());
+
+  char buf = '-';
+  EXPECT_THAT(getxattr(path, name, &buf, XATTR_SIZE_MAX),
+              SyscallSucceedsWithValue(0));
+  EXPECT_EQ(buf, '-');
+}
+
+TEST_F(XattrTest, SetxattrSizeTooLarge) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+
+  // Note that each particular fs implementation may stipulate a lower size
+  // limit, in which case we actually may fail (e.g. error with ENOSPC) for
+  // some sizes under XATTR_SIZE_MAX.
+  size_t size = XATTR_SIZE_MAX + 1;
+  std::vector<char> val(size);
+  EXPECT_THAT(setxattr(path, name, val.data(), size, /*flags=*/0),
+              SyscallFailsWithErrno(E2BIG));
+
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENODATA));
+}
+
+TEST_F(XattrTest, SetxattrNullValueAndNonzeroSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 1, /*flags=*/0),
+              SyscallFailsWithErrno(EFAULT));
+
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENODATA));
+}
+
+TEST_F(XattrTest, SetxattrNullValueAndZeroSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallSucceeds());
+
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallSucceedsWithValue(0));
+}
+
+TEST_F(XattrTest, SetxattrValueTooLargeButOKSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  std::vector<char> val(XATTR_SIZE_MAX + 1);
+  std::fill(val.begin(), val.end(), 'a');
+  size_t size = 1;
+  EXPECT_THAT(setxattr(path, name, val.data(), size, /*flags=*/0),
+              SyscallSucceeds());
+
+  std::vector<char> buf = {'-', '-'};
+  std::vector<char> expected_buf = {'a', '-'};
+  EXPECT_THAT(getxattr(path, name, buf.data(), size),
+              SyscallSucceedsWithValue(size));
+  EXPECT_EQ(buf, expected_buf);
+}
+
+TEST_F(XattrTest, SetxattrReplaceWithSmaller) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  std::vector<char> val = {'a', 'a'};
+  EXPECT_THAT(setxattr(path, name, val.data(), 2, /*flags=*/0),
+              SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name, val.data(), 1, /*flags=*/0),
+              SyscallSucceeds());
+
+  std::vector<char> buf = {'-', '-'};
+  std::vector<char> expected_buf = {'a', '-'};
+  EXPECT_THAT(getxattr(path, name, buf.data(), 2), SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, expected_buf);
+}
+
+TEST_F(XattrTest, SetxattrReplaceWithLarger) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  std::vector<char> val = {'a', 'a'};
+  EXPECT_THAT(setxattr(path, name, val.data(), 1, /*flags=*/0),
+              SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name, val.data(), 2, /*flags=*/0),
+              SyscallSucceeds());
+
+  std::vector<char> buf = {'-', '-'};
+  EXPECT_THAT(getxattr(path, name, buf.data(), 2), SyscallSucceedsWithValue(2));
+  EXPECT_EQ(buf, val);
+}
+
+TEST_F(XattrTest, SetxattrCreateFlag) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, XATTR_CREATE),
+              SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, XATTR_CREATE),
+              SyscallFailsWithErrno(EEXIST));
+
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallSucceedsWithValue(0));
+}
+
+TEST_F(XattrTest, SetxattrReplaceFlag) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, XATTR_REPLACE),
+              SyscallFailsWithErrno(ENODATA));
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, XATTR_REPLACE),
+              SyscallSucceeds());
+
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallSucceedsWithValue(0));
+}
+
+TEST_F(XattrTest, SetxattrInvalidFlags) {
+  const char* path = test_file_name_.c_str();
+  int invalid_flags = 0xff;
+  EXPECT_THAT(setxattr(path, nullptr, nullptr, 0, invalid_flags),
+              SyscallFailsWithErrno(EINVAL));
+}
+
+TEST_F(XattrTest, Getxattr) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  int val = 1234;
+  size_t size = sizeof(val);
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0), SyscallSucceeds());
+
+  int buf = 0;
+  EXPECT_THAT(getxattr(path, name, &buf, size), SyscallSucceedsWithValue(size));
+  EXPECT_EQ(buf, val);
+}
+
+TEST_F(XattrTest, GetxattrSizeSmallerThanValue) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  std::vector<char> val = {'a', 'a'};
+  size_t size = val.size();
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0), SyscallSucceeds());
+
+  char buf = '-';
+  EXPECT_THAT(getxattr(path, name, &buf, 1), SyscallFailsWithErrno(ERANGE));
+  EXPECT_EQ(buf, '-');
+}
+
+TEST_F(XattrTest, GetxattrSizeLargerThanValue) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  EXPECT_THAT(setxattr(path, name, &val, 1, /*flags=*/0), SyscallSucceeds());
+
+  std::vector<char> buf(XATTR_SIZE_MAX);
+  std::fill(buf.begin(), buf.end(), '-');
+  std::vector<char> expected_buf = buf;
+  expected_buf[0] = 'a';
+  EXPECT_THAT(getxattr(path, name, buf.data(), buf.size()),
+              SyscallSucceedsWithValue(1));
+  EXPECT_EQ(buf, expected_buf);
+}
+
+TEST_F(XattrTest, GetxattrZeroSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  EXPECT_THAT(setxattr(path, name, &val, sizeof(val), /*flags=*/0),
+              SyscallSucceeds());
+
+  char buf = '-';
+  EXPECT_THAT(getxattr(path, name, &buf, 0),
+              SyscallSucceedsWithValue(sizeof(val)));
+  EXPECT_EQ(buf, '-');
+}
+
+TEST_F(XattrTest, GetxattrSizeTooLarge) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  EXPECT_THAT(setxattr(path, name, &val, sizeof(val), /*flags=*/0),
+              SyscallSucceeds());
+
+  std::vector<char> buf(XATTR_SIZE_MAX + 1);
+  std::fill(buf.begin(), buf.end(), '-');
+  std::vector<char> expected_buf = buf;
+  expected_buf[0] = 'a';
+  EXPECT_THAT(getxattr(path, name, buf.data(), buf.size()),
+              SyscallSucceedsWithValue(sizeof(val)));
+  EXPECT_EQ(buf, expected_buf);
+}
+
+TEST_F(XattrTest, GetxattrNullValue) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  size_t size = sizeof(val);
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0), SyscallSucceeds());
+
+  EXPECT_THAT(getxattr(path, name, nullptr, size),
+              SyscallFailsWithErrno(EFAULT));
+}
+
+TEST_F(XattrTest, GetxattrNullValueAndZeroSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  char val = 'a';
+  size_t size = sizeof(val);
+  // Set value with zero size.
+  EXPECT_THAT(setxattr(path, name, &val, 0, /*flags=*/0), SyscallSucceeds());
+  // Get value with nonzero size.
+  EXPECT_THAT(getxattr(path, name, nullptr, size), SyscallSucceedsWithValue(0));
+
+  // Set value with nonzero size.
+  EXPECT_THAT(setxattr(path, name, &val, size, /*flags=*/0), SyscallSucceeds());
+  // Get value with zero size.
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallSucceedsWithValue(size));
+}
+
+TEST_F(XattrTest, GetxattrNonexistentName) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENODATA));
+}
+
+TEST_F(XattrTest, Listxattr) {
+  const char* path = test_file_name_.c_str();
+  const std::string name = "user.test";
+  const std::string name2 = "user.test2";
+  const std::string name3 = "user.test3";
+  EXPECT_THAT(setxattr(path, name.c_str(), nullptr, 0, /*flags=*/0),
+              SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name2.c_str(), nullptr, 0, /*flags=*/0),
+              SyscallSucceeds());
+  EXPECT_THAT(setxattr(path, name3.c_str(), nullptr, 0, /*flags=*/0),
+              SyscallSucceeds());
+
+  std::vector<char> list(name.size() + 1 + name2.size() + 1 + name3.size() + 1);
+  char* buf = list.data();
+  EXPECT_THAT(listxattr(path, buf, XATTR_SIZE_MAX),
+              SyscallSucceedsWithValue(list.size()));
+
+  absl::flat_hash_set<std::string> got = {};
+  for (char* p = buf; p < buf + list.size(); p += strlen(p) + 1) {
+    got.insert(std::string{p});
+  }
+
+  absl::flat_hash_set<std::string> expected = {name, name2, name3};
+  EXPECT_EQ(got, expected);
+}
+
+TEST_F(XattrTest, ListxattrNoXattrs) {
+  const char* path = test_file_name_.c_str();
+
+  std::vector<char> list, expected;
+  EXPECT_THAT(listxattr(path, list.data(), sizeof(list)),
+              SyscallSucceedsWithValue(0));
+  EXPECT_EQ(list, expected);
+
+  // Listxattr should succeed if there are no attributes, even if the buffer
+  // passed in is a nullptr.
+  EXPECT_THAT(listxattr(path, nullptr, sizeof(list)),
+              SyscallSucceedsWithValue(0));
+}
+
+TEST_F(XattrTest, ListxattrNullBuffer) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallSucceeds());
+
+  EXPECT_THAT(listxattr(path, nullptr, sizeof(name)),
+              SyscallFailsWithErrno(EFAULT));
+}
+
+TEST_F(XattrTest, ListxattrSizeTooSmall) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallSucceeds());
+
+  char list[sizeof(name) - 1];
+  EXPECT_THAT(listxattr(path, list, sizeof(list)),
+              SyscallFailsWithErrno(ERANGE));
+}
+
+TEST_F(XattrTest, ListxattrZeroSize) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallSucceeds());
+  EXPECT_THAT(listxattr(path, nullptr, 0),
+              SyscallSucceedsWithValue(sizeof(name)));
+}
+
+TEST_F(XattrTest, RemoveXattr) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(setxattr(path, name, nullptr, 0, /*flags=*/0), SyscallSucceeds());
+  EXPECT_THAT(removexattr(path, name), SyscallSucceeds());
+  EXPECT_THAT(getxattr(path, name, nullptr, 0), SyscallFailsWithErrno(ENODATA));
+}
+
+TEST_F(XattrTest, RemoveXattrNonexistentName) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  EXPECT_THAT(removexattr(path, name), SyscallFailsWithErrno(ENODATA));
+}
+
+TEST_F(XattrTest, LXattrOnSymlink) {
+  const char name[] = "user.test";
+  TempPath dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  TempPath link = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateSymlinkTo(dir.path(), test_file_name_));
+
+  EXPECT_THAT(lsetxattr(link.path().c_str(), name, nullptr, 0, 0),
+              SyscallFailsWithErrno(EPERM));
+  EXPECT_THAT(lgetxattr(link.path().c_str(), name, nullptr, 0),
+              SyscallFailsWithErrno(ENODATA));
+  EXPECT_THAT(llistxattr(link.path().c_str(), nullptr, 0),
+              SyscallSucceedsWithValue(0));
+  EXPECT_THAT(lremovexattr(link.path().c_str(), name),
+              SyscallFailsWithErrno(EPERM));
+}
+
+TEST_F(XattrTest, LXattrOnNonsymlink) {
+  const char* path = test_file_name_.c_str();
+  const char name[] = "user.test";
+  int val = 1234;
+  size_t size = sizeof(val);
+  EXPECT_THAT(lsetxattr(path, name, &val, size, /*flags=*/0),
+              SyscallSucceeds());
+
+  int buf = 0;
+  EXPECT_THAT(lgetxattr(path, name, &buf, size),
+              SyscallSucceedsWithValue(size));
+  EXPECT_EQ(buf, val);
+
+  char list[sizeof(name)];
+  EXPECT_THAT(llistxattr(path, list, sizeof(list)),
+              SyscallSucceedsWithValue(sizeof(name)));
+  EXPECT_STREQ(list, name);
+
+  EXPECT_THAT(lremovexattr(path, name), SyscallSucceeds());
+}
+
+TEST_F(XattrTest, XattrWithFD) {
+  const FileDescriptor fd =
+      ASSERT_NO_ERRNO_AND_VALUE(Open(test_file_name_.c_str(), 0));
+  const char name[] = "user.test";
+  int val = 1234;
+  size_t size = sizeof(val);
+  EXPECT_THAT(fsetxattr(fd.get(), name, &val, size, /*flags=*/0),
+              SyscallSucceeds());
+
+  int buf = 0;
+  EXPECT_THAT(fgetxattr(fd.get(), name, &buf, size),
+              SyscallSucceedsWithValue(size));
+  EXPECT_EQ(buf, val);
+
+  char list[sizeof(name)];
+  EXPECT_THAT(flistxattr(fd.get(), list, sizeof(list)),
+              SyscallSucceedsWithValue(sizeof(name)));
+  EXPECT_STREQ(list, name);
+
+  EXPECT_THAT(fremovexattr(fd.get(), name), SyscallSucceeds());
+}
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor