From 9fcc44f991203343438b489389c2b861040086ac Mon Sep 17 00:00:00 2001 From: Chong Cai Date: Wed, 26 May 2021 12:19:11 -0700 Subject: [PATCH] Add verity getdents tests PiperOrigin-RevId: 376001603 --- pkg/sentry/fsimpl/verity/verity.go | 8 ++- test/syscalls/BUILD | 4 ++ test/syscalls/linux/BUILD | 16 +++++ test/syscalls/linux/verity_getdents.cc | 95 ++++++++++++++++++++++++++ 4 files changed, 121 insertions(+), 2 deletions(-) create mode 100644 test/syscalls/linux/verity_getdents.cc diff --git a/pkg/sentry/fsimpl/verity/verity.go b/pkg/sentry/fsimpl/verity/verity.go index fa7696ad6..969003613 100644 --- a/pkg/sentry/fsimpl/verity/verity.go +++ b/pkg/sentry/fsimpl/verity/verity.go @@ -868,6 +868,10 @@ func (fd *fileDescription) IterDirents(ctx context.Context, cb vfs.IterDirentsCa fd.mu.Lock() defer fd.mu.Unlock() + if _, err := fd.lowerFD.Seek(ctx, fd.off, linux.SEEK_SET); err != nil { + return err + } + var ds []vfs.Dirent err := fd.lowerFD.IterDirents(ctx, vfs.IterDirentsCallbackFunc(func(dirent vfs.Dirent) error { // Do not include the Merkle tree files. @@ -890,8 +894,8 @@ func (fd *fileDescription) IterDirents(ctx context.Context, cb vfs.IterDirentsCa return err } - // The result should contain all children plus "." and "..". - if fd.d.verityEnabled() && len(ds) != len(fd.d.childrenNames)+2 { + // The result should be a part of all children plus "." and "..", counting from fd.off. + if fd.d.verityEnabled() && len(ds) != len(fd.d.childrenNames)+2-int(fd.off) { return fd.d.fs.alertIntegrityViolation(fmt.Sprintf("Unexpected children number %d", len(ds))) } diff --git a/test/syscalls/BUILD b/test/syscalls/BUILD index 85412f54b..99743b14a 100644 --- a/test/syscalls/BUILD +++ b/test/syscalls/BUILD @@ -215,6 +215,10 @@ syscall_test( test = "//test/syscalls/linux:getdents_test", ) +syscall_test( + test = "//test/syscalls/linux:verity_getdents_test", +) + syscall_test( test = "//test/syscalls/linux:getrandom_test", ) diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD index f3df889b6..9a912dba8 100644 --- a/test/syscalls/linux/BUILD +++ b/test/syscalls/linux/BUILD @@ -961,6 +961,22 @@ cc_binary( ], ) +cc_binary( + name = "verity_getdents_test", + testonly = 1, + srcs = ["verity_getdents.cc"], + linkstatic = 1, + deps = [ + "//test/util:capability_util", + gtest, + "//test/util:fs_util", + "//test/util:temp_path", + "//test/util:test_main", + "//test/util:test_util", + "//test/util:verity_util", + ], +) + cc_binary( name = "getrandom_test", testonly = 1, diff --git a/test/syscalls/linux/verity_getdents.cc b/test/syscalls/linux/verity_getdents.cc new file mode 100644 index 000000000..093595dd3 --- /dev/null +++ b/test/syscalls/linux/verity_getdents.cc @@ -0,0 +1,95 @@ +// Copyright 2021 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 +#include +#include +#include +#include + +#include +#include + +#include "gmock/gmock.h" +#include "gtest/gtest.h" +#include "test/util/capability_util.h" +#include "test/util/fs_util.h" +#include "test/util/temp_path.h" +#include "test/util/test_util.h" +#include "test/util/verity_util.h" + +namespace gvisor { +namespace testing { + +namespace { + +class GetDentsTest : public ::testing::Test { + protected: + void SetUp() override { + // Verity is implemented in VFS2. + SKIP_IF(IsRunningWithVFS1()); + + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); + // Mount a tmpfs file system, to be wrapped by a verity fs. + tmpfs_dir_ = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir()); + ASSERT_THAT(mount("", tmpfs_dir_.path().c_str(), "tmpfs", 0, ""), + SyscallSucceeds()); + + // Create a new file in the tmpfs mount. + file_ = ASSERT_NO_ERRNO_AND_VALUE( + TempPath::CreateFileWith(tmpfs_dir_.path(), kContents, 0777)); + filename_ = Basename(file_.path()); + } + + TempPath tmpfs_dir_; + TempPath file_; + std::string filename_; +}; + +TEST_F(GetDentsTest, GetDents) { + std::string verity_dir = + ASSERT_NO_ERRNO_AND_VALUE(MountVerity(tmpfs_dir_.path(), filename_)); + + std::vector expect = {".", "..", filename_}; + EXPECT_NO_ERRNO(DirContains(verity_dir, expect, /*exclude=*/{})); +} + +TEST_F(GetDentsTest, Deleted) { + std::string verity_dir = + ASSERT_NO_ERRNO_AND_VALUE(MountVerity(tmpfs_dir_.path(), filename_)); + + EXPECT_THAT(unlink(JoinPath(tmpfs_dir_.path(), filename_).c_str()), + SyscallSucceeds()); + + EXPECT_THAT(DirContains(verity_dir, /*expect=*/{}, /*exclude=*/{}), + PosixErrorIs(EIO, ::testing::_)); +} + +TEST_F(GetDentsTest, Renamed) { + std::string verity_dir = + ASSERT_NO_ERRNO_AND_VALUE(MountVerity(tmpfs_dir_.path(), filename_)); + + std::string new_file_name = "renamed-" + filename_; + EXPECT_THAT(rename(JoinPath(tmpfs_dir_.path(), filename_).c_str(), + JoinPath(tmpfs_dir_.path(), new_file_name).c_str()), + SyscallSucceeds()); + + EXPECT_THAT(DirContains(verity_dir, /*expect=*/{}, /*exclude=*/{}), + PosixErrorIs(EIO, ::testing::_)); +} + +} // namespace + +} // namespace testing +} // namespace gvisor