diff options
author | tensor5 | 2021-09-27 06:08:25 +0000 |
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committer | tensor5 | 2021-09-27 06:08:25 +0000 |
commit | 08d1f2f5701e8f31e0c359007aa25efeb3c74254 (patch) | |
tree | fffe60aa576f4b9c1406a228bb5ba063fd20b5ea /linux-sandbox-syscall-broker-use-struct-kernel_stat.patch | |
download | aur-08d1f2f5701e8f31e0c359007aa25efeb3c74254.tar.gz |
addpkg: electron14 14.0.1
git-svn-id: file:///srv/repos/svn-community/svn@1025724 9fca08f4-af9d-4005-b8df-a31f2cc04f65
Diffstat (limited to 'linux-sandbox-syscall-broker-use-struct-kernel_stat.patch')
-rw-r--r-- | linux-sandbox-syscall-broker-use-struct-kernel_stat.patch | 1384 |
1 files changed, 1384 insertions, 0 deletions
diff --git a/linux-sandbox-syscall-broker-use-struct-kernel_stat.patch b/linux-sandbox-syscall-broker-use-struct-kernel_stat.patch new file mode 100644 index 000000000000..7aa43a7aac5c --- /dev/null +++ b/linux-sandbox-syscall-broker-use-struct-kernel_stat.patch @@ -0,0 +1,1384 @@ +From 4b438323d68840453b5ef826c3997568e2e0e8c7 Mon Sep 17 00:00:00 2001 +From: Matthew Denton <mpdenton@chromium.org> +Date: Mon, 19 Jul 2021 14:03:13 +0000 +Subject: [PATCH] Reland "Reland "Linux sandbox syscall broker: use struct + kernel_stat"" + +This reverts commit ff277a52ece0b216617d770f201ed66955fe70b9. + +Reason for revert: reland + +The fix included in the reland is that fstatat64() needs to be +allowed in the broker process's seccomp policy. + +This CL also includes some extra tests that the kernel_stat structures +match the layout the kernel expects. + +Bug: 1164975, 1199431 +Test: trogdor Chromebook successfully boots and allows login. + +Original change's description: +> Revert "Reland "Linux sandbox syscall broker: use struct kernel_stat"" +> +> This reverts commit cffbc4432af79f720ae3c75dff380b853701bd64. +> +> Reason for revert: https://bugs.chromium.org/p/chromium/issues/detail?id=1199431 +> +> Original change's description: +> > Reland "Linux sandbox syscall broker: use struct kernel_stat" +> > +> > This reverts commit 23030dc650cdfa22631f25bef937905f27f06a2c. +> > +> > Original change's description: +> > > Revert "Linux sandbox syscall broker: use struct kernel_stat" +> > > +> > > This reverts commit 784b0fcd8a3ca6bcd3acb9cfd624ec9cbbac2789. +> > > +> > > Reason for revert: Causing failure in +> > > Step "sandbox_linux_unittests" failing on builder "Linux ChromiumOS MSan Tests" +> > > See crbug.com/1198480 +> > > +> > > Original change's description: +> > > > Linux sandbox syscall broker: use struct kernel_stat +> > > > +> > > > The struct stat used in libc is different (in size and field ordering) +> > > > from the structure assumed by the Linux kernel. So, when emulating +> > > > system calls, we need to use the struct definition the kernel expects. +> > > > +> > > > This CL adds linux_stat.h that includes definitions of the different +> > > > kernel structs. +> > > > +> > > > Change-Id: I53cad35c2251dff0f6b7ea77528cfa58ef3cab4a +> > > > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2780876 +> > > > Commit-Queue: Matthew Denton <mpdenton@chromium.org> +> > > > Reviewed-by: Robert Sesek <rsesek@chromium.org> +> > > > Cr-Commit-Position: refs/heads/master@{#871767} +> > > +> > > Change-Id: Icbec38f2103c8424dec79ab1870b97c3e83f9361 +> > > No-Presubmit: true +> > > No-Tree-Checks: true +> > > No-Try: true +> > > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2821812 +> > > Auto-Submit: Victor Vianna <victorvianna@google.com> +> > > Owners-Override: Victor Vianna <victorvianna@google.com> +> > > Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com> +> > > Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com> +> > > Cr-Commit-Position: refs/heads/master@{#871882} +> > +> > Change-Id: I1f39bb5242961474def594ff7dbea52009f2cee4 +> > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2824115 +> > Auto-Submit: Matthew Denton <mpdenton@chromium.org> +> > Commit-Queue: Matthew Denton <mpdenton@chromium.org> +> > Reviewed-by: Robert Sesek <rsesek@chromium.org> +> > Cr-Commit-Position: refs/heads/master@{#872812} +> +> Fixed: 1199431 +> Change-Id: Iebfc0c48201bf22ff9c54d8d5c8a43d26a880098 +> No-Presubmit: true +> No-Tree-Checks: true +> No-Try: true +> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2830459 +> Auto-Submit: Kyle Horimoto <khorimoto@chromium.org> +> Commit-Queue: Matthew Denton <mpdenton@chromium.org> +> Commit-Queue: Kinuko Yasuda <kinuko@chromium.org> +> Reviewed-by: Matthew Denton <mpdenton@chromium.org> +> Reviewed-by: Kinuko Yasuda <kinuko@chromium.org> +> Owners-Override: Kinuko Yasuda <kinuko@chromium.org> +> Cr-Commit-Position: refs/heads/master@{#873173} + +Change-Id: Ibe6a485070f33489aaa157b51b908c2d23d174d7 +Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2848936 +Reviewed-by: Robert Sesek <rsesek@chromium.org> +Commit-Queue: Matthew Denton <mpdenton@chromium.org> +Cr-Commit-Position: refs/heads/master@{#902981} +--- + sandbox/linux/BUILD.gn | 1 + + .../seccomp_broker_process_unittest.cc | 40 +++- + sandbox/linux/seccomp-bpf-helpers/DEPS | 1 - + ...scall_parameters_restrictions_unittests.cc | 4 - + sandbox/linux/services/syscall_wrappers.cc | 50 ++++- + sandbox/linux/services/syscall_wrappers.h | 15 ++ + .../services/syscall_wrappers_unittest.cc | 129 +++++++++++- + sandbox/linux/syscall_broker/DEPS | 3 +- + sandbox/linux/syscall_broker/broker_client.cc | 4 +- + sandbox/linux/syscall_broker/broker_client.h | 4 +- + sandbox/linux/syscall_broker/broker_host.cc | 23 ++- + .../syscall_broker/broker_process_unittest.cc | 74 +++---- + .../remote_syscall_arg_handler_unittest.cc | 36 ++-- + .../syscall_broker/syscall_dispatcher.cc | 67 ++++--- + .../linux/syscall_broker/syscall_dispatcher.h | 27 ++- + sandbox/linux/system_headers/linux_stat.h | 188 ++++++++++++++++++ + sandbox/linux/system_headers/linux_time.h | 26 +++ + sandbox/linux/tests/test_utils.cc | 15 ++ + sandbox/linux/tests/test_utils.h | 2 + + .../policy/linux/bpf_broker_policy_linux.cc | 4 +- + 20 files changed, 595 insertions(+), 118 deletions(-) + create mode 100644 sandbox/linux/system_headers/linux_stat.h + +diff --git a/sandbox/linux/BUILD.gn b/sandbox/linux/BUILD.gn +index 2f778dd0bc..ccbbc91716 100644 +--- a/sandbox/linux/BUILD.gn ++++ b/sandbox/linux/BUILD.gn +@@ -443,6 +443,7 @@ source_set("sandbox_services_headers") { + "system_headers/linux_ptrace.h", + "system_headers/linux_seccomp.h", + "system_headers/linux_signal.h", ++ "system_headers/linux_stat.h", + "system_headers/linux_syscalls.h", + "system_headers/linux_time.h", + "system_headers/linux_ucontext.h", +diff --git a/sandbox/linux/integration_tests/seccomp_broker_process_unittest.cc b/sandbox/linux/integration_tests/seccomp_broker_process_unittest.cc +index 9da9c68911..8a941983b1 100644 +--- a/sandbox/linux/integration_tests/seccomp_broker_process_unittest.cc ++++ b/sandbox/linux/integration_tests/seccomp_broker_process_unittest.cc +@@ -34,6 +34,7 @@ + #include "sandbox/linux/syscall_broker/broker_file_permission.h" + #include "sandbox/linux/syscall_broker/broker_process.h" + #include "sandbox/linux/system_headers/linux_seccomp.h" ++#include "sandbox/linux/system_headers/linux_stat.h" + #include "sandbox/linux/system_headers/linux_syscalls.h" + #include "sandbox/linux/tests/scoped_temporary_file.h" + #include "sandbox/linux/tests/test_utils.h" +@@ -202,6 +203,26 @@ namespace { + // not accept this as a valid error number. E.g. bionic accepts up to 255, glibc + // and musl up to 4096. + const int kFakeErrnoSentinel = 254; ++ ++void ConvertKernelStatToLibcStat(default_stat_struct& in_stat, ++ struct stat& out_stat) { ++ out_stat.st_dev = in_stat.st_dev; ++ out_stat.st_ino = in_stat.st_ino; ++ out_stat.st_mode = in_stat.st_mode; ++ out_stat.st_nlink = in_stat.st_nlink; ++ out_stat.st_uid = in_stat.st_uid; ++ out_stat.st_gid = in_stat.st_gid; ++ out_stat.st_rdev = in_stat.st_rdev; ++ out_stat.st_size = in_stat.st_size; ++ out_stat.st_blksize = in_stat.st_blksize; ++ out_stat.st_blocks = in_stat.st_blocks; ++ out_stat.st_atim.tv_sec = in_stat.st_atime_; ++ out_stat.st_atim.tv_nsec = in_stat.st_atime_nsec_; ++ out_stat.st_mtim.tv_sec = in_stat.st_mtime_; ++ out_stat.st_mtim.tv_nsec = in_stat.st_mtime_nsec_; ++ out_stat.st_ctim.tv_sec = in_stat.st_ctime_; ++ out_stat.st_ctim.tv_nsec = in_stat.st_ctime_nsec_; ++} + } // namespace + + // There are a variety of ways to make syscalls in a sandboxed process. One is +@@ -217,6 +238,10 @@ class Syscaller { + + virtual int Open(const char* filepath, int flags) = 0; + virtual int Access(const char* filepath, int mode) = 0; ++ // NOTE: we use struct stat instead of default_stat_struct, to make the libc ++ // syscaller simpler. Copying from default_stat_struct (the structure returned ++ // from a stat sycall) to struct stat (the structure exposed by a libc to its ++ // users) is simpler than going in the opposite direction. + virtual int Stat(const char* filepath, + bool follow_links, + struct stat* statbuf) = 0; +@@ -243,8 +268,12 @@ class IPCSyscaller : public Syscaller { + int Stat(const char* filepath, + bool follow_links, + struct stat* statbuf) override { +- return broker_->GetBrokerClientSignalBased()->Stat(filepath, follow_links, +- statbuf); ++ default_stat_struct buf; ++ int ret = broker_->GetBrokerClientSignalBased()->DefaultStatForTesting( ++ filepath, follow_links, &buf); ++ if (ret >= 0) ++ ConvertKernelStatToLibcStat(buf, *statbuf); ++ return ret; + } + + int Rename(const char* oldpath, const char* newpath) override { +@@ -300,10 +329,13 @@ class DirectSyscaller : public Syscaller { + int Stat(const char* filepath, + bool follow_links, + struct stat* statbuf) override { +- int ret = follow_links ? syscall(__NR_stat, filepath, statbuf) +- : syscall(__NR_lstat, filepath, statbuf); ++ struct kernel_stat buf; ++ int ret = syscall(__NR_newfstatat, AT_FDCWD, filepath, &buf, ++ follow_links ? 0 : AT_SYMLINK_NOFOLLOW); + if (ret < 0) + return -errno; ++ ++ ConvertKernelStatToLibcStat(buf, *statbuf); + return ret; + } + +diff --git a/sandbox/linux/seccomp-bpf-helpers/DEPS b/sandbox/linux/seccomp-bpf-helpers/DEPS +index 4419fd1da3..95d1bb6cbb 100644 +--- a/sandbox/linux/seccomp-bpf-helpers/DEPS ++++ b/sandbox/linux/seccomp-bpf-helpers/DEPS +@@ -3,5 +3,4 @@ include_rules = [ + "+sandbox/linux/seccomp-bpf", + "+sandbox/linux/services", + "+sandbox/linux/system_headers", +- "+third_party/lss/linux_syscall_support.h", + ] +diff --git a/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc b/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc +index 903e702eab..76c393032c 100644 +--- a/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc ++++ b/sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions_unittests.cc +@@ -37,10 +37,6 @@ + #include "sandbox/linux/system_headers/linux_time.h" + #include "sandbox/linux/tests/unit_tests.h" + +-#if !defined(OS_ANDROID) +-#include "third_party/lss/linux_syscall_support.h" // for MAKE_PROCESS_CPUCLOCK +-#endif +- + namespace sandbox { + + namespace { +diff --git a/sandbox/linux/services/syscall_wrappers.cc b/sandbox/linux/services/syscall_wrappers.cc +index fcfd2aa129..3bec18a14e 100644 +--- a/sandbox/linux/services/syscall_wrappers.cc ++++ b/sandbox/linux/services/syscall_wrappers.cc +@@ -4,6 +4,7 @@ + + #include "sandbox/linux/services/syscall_wrappers.h" + ++#include <fcntl.h> + #include <pthread.h> + #include <sched.h> + #include <setjmp.h> +@@ -14,11 +15,13 @@ + #include <unistd.h> + #include <cstring> + ++#include "base/check.h" + #include "base/compiler_specific.h" + #include "base/logging.h" + #include "build/build_config.h" + #include "sandbox/linux/system_headers/capability.h" + #include "sandbox/linux/system_headers/linux_signal.h" ++#include "sandbox/linux/system_headers/linux_stat.h" + #include "sandbox/linux/system_headers/linux_syscalls.h" + + namespace sandbox { +@@ -217,7 +220,7 @@ asm( + #undef STR + #undef XSTR + +-#endif ++#endif // defined(ARCH_CPU_X86_FAMILY) + + int sys_sigaction(int signum, + const struct sigaction* act, +@@ -241,7 +244,7 @@ int sys_sigaction(int signum, + #error "Unsupported architecture." + #endif + } +-#endif ++#endif // defined(ARCH_CPU_X86_FAMILY) + } + + LinuxSigAction linux_oldact = {}; +@@ -259,6 +262,47 @@ int sys_sigaction(int signum, + return result; + } + +-#endif // defined(MEMORY_SANITIZER) ++#endif // !defined(OS_NACL_NONSFI) ++ ++int sys_stat(const char* path, struct kernel_stat* stat_buf) { ++ int res; ++#if !defined(__NR_stat) ++ res = syscall(__NR_newfstatat, AT_FDCWD, path, stat_buf, 0); ++#else ++ res = syscall(__NR_stat, path, stat_buf); ++#endif ++ if (res == 0) ++ MSAN_UNPOISON(stat_buf, sizeof(*stat_buf)); ++ return res; ++} ++ ++int sys_lstat(const char* path, struct kernel_stat* stat_buf) { ++ int res; ++#if !defined(__NR_lstat) ++ res = syscall(__NR_newfstatat, AT_FDCWD, path, stat_buf, AT_SYMLINK_NOFOLLOW); ++#else ++ res = syscall(__NR_lstat, path, stat_buf); ++#endif ++ if (res == 0) ++ MSAN_UNPOISON(stat_buf, sizeof(*stat_buf)); ++ return res; ++} ++ ++int sys_fstatat64(int dirfd, ++ const char* pathname, ++ struct kernel_stat64* stat_buf, ++ int flags) { ++#if defined(__NR_fstatat64) ++ int res = syscall(__NR_fstatat64, dirfd, pathname, stat_buf, flags); ++ if (res == 0) ++ MSAN_UNPOISON(stat_buf, sizeof(*stat_buf)); ++ return res; ++#else // defined(__NR_fstatat64) ++ // We should not reach here on 64-bit systems, as the *stat*64() are only ++ // necessary on 32-bit. ++ RAW_CHECK(false); ++ return -ENOSYS; ++#endif ++} + + } // namespace sandbox +diff --git a/sandbox/linux/services/syscall_wrappers.h b/sandbox/linux/services/syscall_wrappers.h +index 1975bfbd88..b55340e4a2 100644 +--- a/sandbox/linux/services/syscall_wrappers.h ++++ b/sandbox/linux/services/syscall_wrappers.h +@@ -17,6 +17,8 @@ struct sock_fprog; + struct rlimit64; + struct cap_hdr; + struct cap_data; ++struct kernel_stat; ++struct kernel_stat64; + + namespace sandbox { + +@@ -84,6 +86,19 @@ SANDBOX_EXPORT int sys_sigaction(int signum, + const struct sigaction* act, + struct sigaction* oldact); + ++// Some architectures do not have stat() and lstat() syscalls. In that case, ++// these wrappers will use newfstatat(), which is available on all other ++// architectures, with the same capabilities as stat() and lstat(). ++SANDBOX_EXPORT int sys_stat(const char* path, struct kernel_stat* stat_buf); ++SANDBOX_EXPORT int sys_lstat(const char* path, struct kernel_stat* stat_buf); ++ ++// Takes care of unpoisoning |stat_buf| for MSAN. Check-fails if fstatat64() is ++// not a supported syscall on the current platform. ++SANDBOX_EXPORT int sys_fstatat64(int dirfd, ++ const char* pathname, ++ struct kernel_stat64* stat_buf, ++ int flags); ++ + } // namespace sandbox + + #endif // SANDBOX_LINUX_SERVICES_SYSCALL_WRAPPERS_H_ +diff --git a/sandbox/linux/services/syscall_wrappers_unittest.cc b/sandbox/linux/services/syscall_wrappers_unittest.cc +index 32820f60a8..64b9cea80f 100644 +--- a/sandbox/linux/services/syscall_wrappers_unittest.cc ++++ b/sandbox/linux/services/syscall_wrappers_unittest.cc +@@ -5,15 +5,19 @@ + #include "sandbox/linux/services/syscall_wrappers.h" + + #include <stdint.h> ++#include <string.h> + #include <sys/syscall.h> + #include <sys/types.h> + #include <sys/wait.h> + #include <unistd.h> +-#include <cstring> + ++#include "base/logging.h" ++#include "base/memory/page_size.h" + #include "base/posix/eintr_wrapper.h" + #include "build/build_config.h" + #include "sandbox/linux/system_headers/linux_signal.h" ++#include "sandbox/linux/system_headers/linux_stat.h" ++#include "sandbox/linux/tests/scoped_temporary_file.h" + #include "sandbox/linux/tests/test_utils.h" + #include "sandbox/linux/tests/unit_tests.h" + #include "testing/gtest/include/gtest/gtest.h" +@@ -93,6 +97,129 @@ TEST(SyscallWrappers, LinuxSigSet) { + linux_sigset); + } + ++TEST(SyscallWrappers, Stat) { ++ // Create a file to stat, with 12 bytes of data. ++ ScopedTemporaryFile tmp_file; ++ EXPECT_EQ(12, write(tmp_file.fd(), "blahblahblah", 12)); ++ ++ // To test we have the correct stat structures for each kernel/platform, we ++ // will right-align them on a page, with a guard page after. ++ char* two_pages = static_cast<char*>(TestUtils::MapPagesOrDie(2)); ++ TestUtils::MprotectLastPageOrDie(two_pages, 2); ++ char* page1_end = two_pages + base::GetPageSize(); ++ ++ // First, check that calling stat with |stat_buf| pointing to the last byte on ++ // a page causes EFAULT. ++ int res = sys_stat(tmp_file.full_file_name(), ++ reinterpret_cast<struct kernel_stat*>(page1_end - 1)); ++ ASSERT_EQ(res, -1); ++ ASSERT_EQ(errno, EFAULT); ++ ++ // Now, check that we have the correctly sized stat structure. ++ struct kernel_stat* sb = reinterpret_cast<struct kernel_stat*>( ++ page1_end - sizeof(struct kernel_stat)); ++ // Memset to c's so we can check the kernel zero'd the padding... ++ memset(sb, 'c', sizeof(struct kernel_stat)); ++ res = sys_stat(tmp_file.full_file_name(), sb); ++ ASSERT_EQ(res, 0); ++ ++ // Following fields may never be consistent but should be non-zero. ++ // Don't trust the platform to define fields with any particular sign. ++ EXPECT_NE(0u, static_cast<unsigned int>(sb->st_dev)); ++ EXPECT_NE(0u, static_cast<unsigned int>(sb->st_ino)); ++ EXPECT_NE(0u, static_cast<unsigned int>(sb->st_mode)); ++ EXPECT_NE(0u, static_cast<unsigned int>(sb->st_blksize)); ++ EXPECT_NE(0u, static_cast<unsigned int>(sb->st_blocks)); ++ ++// We are the ones that made the file. ++// Note: normally gid and uid overflow on backwards-compatible 32-bit systems ++// and we end up with dummy uids and gids in place here. ++#if defined(ARCH_CPU_64_BITS) ++ EXPECT_EQ(geteuid(), sb->st_uid); ++ EXPECT_EQ(getegid(), sb->st_gid); ++#endif ++ ++ // Wrote 12 bytes above which should fit in one block. ++ EXPECT_EQ(12u, sb->st_size); ++ ++ // Can't go backwards in time, 1500000000 was some time ago. ++ EXPECT_LT(1500000000u, static_cast<unsigned int>(sb->st_atime_)); ++ EXPECT_LT(1500000000u, static_cast<unsigned int>(sb->st_mtime_)); ++ EXPECT_LT(1500000000u, static_cast<unsigned int>(sb->st_ctime_)); ++ ++ // Checking the padding for good measure. ++#if defined(__x86_64__) ++ EXPECT_EQ(0u, sb->__pad0); ++ EXPECT_EQ(0u, sb->__unused4[0]); ++ EXPECT_EQ(0u, sb->__unused4[1]); ++ EXPECT_EQ(0u, sb->__unused4[2]); ++#elif defined(__aarch64__) ++ EXPECT_EQ(0u, sb->__pad1); ++ EXPECT_EQ(0, sb->__pad2); ++ EXPECT_EQ(0u, sb->__unused4); ++ EXPECT_EQ(0u, sb->__unused5); ++#endif ++} ++ ++TEST(SyscallWrappers, LStat) { ++ // Create a file to stat, with 12 bytes of data. ++ ScopedTemporaryFile tmp_file; ++ EXPECT_EQ(12, write(tmp_file.fd(), "blahblahblah", 12)); ++ ++ // Also create a symlink. ++ std::string symlink_name; ++ { ++ ScopedTemporaryFile tmp_file2; ++ symlink_name = tmp_file2.full_file_name(); ++ } ++ int rc = symlink(tmp_file.full_file_name(), symlink_name.c_str()); ++ if (rc != 0) { ++ PLOG(ERROR) << "Couldn't symlink " << symlink_name << " to target " ++ << tmp_file.full_file_name(); ++ GTEST_FAIL(); ++ } ++ ++ struct kernel_stat lstat_info; ++ rc = sys_lstat(symlink_name.c_str(), &lstat_info); ++ if (rc < 0 && errno == EOVERFLOW) { ++ GTEST_SKIP(); ++ } ++ if (rc != 0) { ++ PLOG(ERROR) << "Couldn't sys_lstat " << symlink_name; ++ GTEST_FAIL(); ++ } ++ ++ struct kernel_stat stat_info; ++ rc = sys_stat(symlink_name.c_str(), &stat_info); ++ if (rc < 0 && errno == EOVERFLOW) { ++ GTEST_SKIP(); ++ } ++ if (rc != 0) { ++ PLOG(ERROR) << "Couldn't sys_stat " << symlink_name; ++ GTEST_FAIL(); ++ } ++ ++ struct kernel_stat tmp_file_stat_info; ++ rc = sys_stat(tmp_file.full_file_name(), &tmp_file_stat_info); ++ if (rc < 0 && errno == EOVERFLOW) { ++ GTEST_SKIP(); ++ } ++ if (rc != 0) { ++ PLOG(ERROR) << "Couldn't sys_stat " << tmp_file.full_file_name(); ++ GTEST_FAIL(); ++ } ++ ++ // lstat should produce information about a symlink. ++ ASSERT_TRUE(S_ISLNK(lstat_info.st_mode)); ++ ++ // stat-ing symlink_name and tmp_file should produce the same inode. ++ ASSERT_EQ(stat_info.st_ino, tmp_file_stat_info.st_ino); ++ ++ // lstat-ing symlink_name should give a different inode than stat-ing ++ // symlink_name. ++ ASSERT_NE(stat_info.st_ino, lstat_info.st_ino); ++} ++ + } // namespace + + } // namespace sandbox +diff --git a/sandbox/linux/syscall_broker/DEPS b/sandbox/linux/syscall_broker/DEPS +index c477f7d363..149c463b06 100644 +--- a/sandbox/linux/syscall_broker/DEPS ++++ b/sandbox/linux/syscall_broker/DEPS +@@ -1,4 +1,5 @@ + include_rules = [ +- "+sandbox/linux/system_headers", + "+sandbox/linux/bpf_dsl", ++ "+sandbox/linux/services", ++ "+sandbox/linux/system_headers", + ] +diff --git a/sandbox/linux/syscall_broker/broker_client.cc b/sandbox/linux/syscall_broker/broker_client.cc +index 6b1b5be433..e24f659fcf 100644 +--- a/sandbox/linux/syscall_broker/broker_client.cc ++++ b/sandbox/linux/syscall_broker/broker_client.cc +@@ -166,7 +166,7 @@ int BrokerClient::Rmdir(const char* path) const { + + int BrokerClient::Stat(const char* pathname, + bool follow_links, +- struct stat* sb) const { ++ struct kernel_stat* sb) const { + if (!pathname || !sb) + return -EFAULT; + +@@ -181,7 +181,7 @@ int BrokerClient::Stat(const char* pathname, + + int BrokerClient::Stat64(const char* pathname, + bool follow_links, +- struct stat64* sb) const { ++ struct kernel_stat64* sb) const { + if (!pathname || !sb) + return -EFAULT; + +diff --git a/sandbox/linux/syscall_broker/broker_client.h b/sandbox/linux/syscall_broker/broker_client.h +index 05e14c83f2..26ca78101c 100644 +--- a/sandbox/linux/syscall_broker/broker_client.h ++++ b/sandbox/linux/syscall_broker/broker_client.h +@@ -61,10 +61,10 @@ class SANDBOX_EXPORT BrokerClient : public SyscallDispatcher { + int Rmdir(const char* path) const override; + int Stat(const char* pathname, + bool follow_links, +- struct stat* sb) const override; ++ struct kernel_stat* sb) const override; + int Stat64(const char* pathname, + bool follow_links, +- struct stat64* sb) const override; ++ struct kernel_stat64* sb) const override; + int Unlink(const char* unlink) const override; + + private: +diff --git a/sandbox/linux/syscall_broker/broker_host.cc b/sandbox/linux/syscall_broker/broker_host.cc +index 1cd03a18df..1cdc01a888 100644 +--- a/sandbox/linux/syscall_broker/broker_host.cc ++++ b/sandbox/linux/syscall_broker/broker_host.cc +@@ -20,9 +20,11 @@ + #include "base/files/scoped_file.h" + #include "base/logging.h" + #include "base/posix/eintr_wrapper.h" ++#include "sandbox/linux/services/syscall_wrappers.h" + #include "sandbox/linux/syscall_broker/broker_command.h" + #include "sandbox/linux/syscall_broker/broker_permission_list.h" + #include "sandbox/linux/syscall_broker/broker_simple_message.h" ++#include "sandbox/linux/system_headers/linux_stat.h" + #include "sandbox/linux/system_headers/linux_syscalls.h" + + namespace sandbox { +@@ -193,10 +195,12 @@ void StatFileForIPC(const BrokerCommandSet& allowed_command_set, + RAW_CHECK(reply->AddIntToMessage(-permission_list.denied_errno())); + return; + } ++ + if (command_type == COMMAND_STAT) { +- struct stat sb; +- int sts = +- follow_links ? stat(file_to_access, &sb) : lstat(file_to_access, &sb); ++ struct kernel_stat sb; ++ ++ int sts = follow_links ? sandbox::sys_stat(file_to_access, &sb) ++ : sandbox::sys_lstat(file_to_access, &sb); + if (sts < 0) { + RAW_CHECK(reply->AddIntToMessage(-errno)); + return; +@@ -205,10 +209,12 @@ void StatFileForIPC(const BrokerCommandSet& allowed_command_set, + RAW_CHECK( + reply->AddDataToMessage(reinterpret_cast<char*>(&sb), sizeof(sb))); + } else { ++#if defined(__NR_fstatat64) + DCHECK(command_type == COMMAND_STAT64); +- struct stat64 sb; +- int sts = follow_links ? stat64(file_to_access, &sb) +- : lstat64(file_to_access, &sb); ++ struct kernel_stat64 sb; ++ ++ int sts = sandbox::sys_fstatat64(AT_FDCWD, file_to_access, &sb, ++ follow_links ? 0 : AT_SYMLINK_NOFOLLOW); + if (sts < 0) { + RAW_CHECK(reply->AddIntToMessage(-errno)); + return; +@@ -216,6 +222,11 @@ void StatFileForIPC(const BrokerCommandSet& allowed_command_set, + RAW_CHECK(reply->AddIntToMessage(0)); + RAW_CHECK( + reply->AddDataToMessage(reinterpret_cast<char*>(&sb), sizeof(sb))); ++#else // defined(__NR_fstatat64) ++ // We should not reach here on 64-bit systems, as the *stat*64() are only ++ // necessary on 32-bit. ++ RAW_CHECK(false); ++#endif + } + } + +diff --git a/sandbox/linux/syscall_broker/broker_process_unittest.cc b/sandbox/linux/syscall_broker/broker_process_unittest.cc +index 55ba6bccb2..c65f25a78a 100644 +--- a/sandbox/linux/syscall_broker/broker_process_unittest.cc ++++ b/sandbox/linux/syscall_broker/broker_process_unittest.cc +@@ -811,7 +811,7 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + const char* bad_leading_path5 = "/mbogo/fictitioux"; + const char* bad_leading_path6 = "/mbogo/fictitiousa"; + +- struct stat sb; ++ default_stat_struct sb; + + { + // Actual file with permissions to see file but command not allowed. +@@ -824,7 +824,7 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + + memset(&sb, 0, sizeof(sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + tempfile_name, follow_links, &sb)); + } + +@@ -840,7 +840,7 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + + memset(&sb, 0, sizeof(sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + nonesuch_name, follow_links, &sb)); + } + { +@@ -852,7 +852,7 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + + memset(&sb, 0, sizeof(sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + tempfile_name, follow_links, &sb)); + } + { +@@ -864,38 +864,39 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + ASSERT_TRUE(open_broker.Init(base::BindOnce(&NoOpCallback))); + + memset(&sb, 0, sizeof(sb)); +- EXPECT_EQ(-ENOENT, open_broker.GetBrokerClientSignalBased()->Stat( +- nonesuch_name, follow_links, &sb)); ++ EXPECT_EQ(-ENOENT, ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( ++ nonesuch_name, follow_links, &sb)); + + // Gets denied all the way back to root since no create permission. + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + leading_path1, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + leading_path2, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + leading_path3, follow_links, &sb)); + + // Not fooled by substrings. + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path1, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path2, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path3, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path4, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path5, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path6, follow_links, &sb)); + } + { +@@ -907,37 +908,41 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + ASSERT_TRUE(open_broker.Init(base::BindOnce(&NoOpCallback))); + + memset(&sb, 0, sizeof(sb)); +- EXPECT_EQ(-ENOENT, open_broker.GetBrokerClientSignalBased()->Stat( +- nonesuch_name, follow_links, &sb)); ++ EXPECT_EQ(-ENOENT, ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( ++ nonesuch_name, follow_links, &sb)); + + // Gets ENOENT all the way back to root since it has create permission. +- EXPECT_EQ(-ENOENT, open_broker.GetBrokerClientSignalBased()->Stat( +- leading_path1, follow_links, &sb)); +- EXPECT_EQ(-ENOENT, open_broker.GetBrokerClientSignalBased()->Stat( +- leading_path2, follow_links, &sb)); ++ EXPECT_EQ(-ENOENT, ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( ++ leading_path1, follow_links, &sb)); ++ EXPECT_EQ(-ENOENT, ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( ++ leading_path2, follow_links, &sb)); + + // But can always get the root. +- EXPECT_EQ(0, open_broker.GetBrokerClientSignalBased()->Stat( +- leading_path3, follow_links, &sb)); ++ EXPECT_EQ(0, ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( ++ leading_path3, follow_links, &sb)); + + // Not fooled by substrings. + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path1, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path2, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path3, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path4, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path5, follow_links, &sb)); + EXPECT_EQ(-kFakeErrnoSentinel, +- open_broker.GetBrokerClientSignalBased()->Stat( ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( + bad_leading_path6, follow_links, &sb)); + } + { +@@ -949,8 +954,9 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + ASSERT_TRUE(open_broker.Init(base::BindOnce(&NoOpCallback))); + + memset(&sb, 0, sizeof(sb)); +- EXPECT_EQ(0, open_broker.GetBrokerClientSignalBased()->Stat( +- tempfile_name, follow_links, &sb)); ++ EXPECT_EQ(0, ++ open_broker.GetBrokerClientSignalBased()->DefaultStatForTesting( ++ tempfile_name, follow_links, &sb)); + + // Following fields may never be consistent but should be non-zero. + // Don't trust the platform to define fields with any particular sign. +@@ -968,9 +974,9 @@ void TestStatHelper(bool fast_check_in_client, bool follow_links) { + EXPECT_EQ(12, sb.st_size); + + // Can't go backwards in time, 1500000000 was some time ago. +- EXPECT_LT(1500000000u, static_cast<unsigned int>(sb.st_atime)); +- EXPECT_LT(1500000000u, static_cast<unsigned int>(sb.st_mtime)); +- EXPECT_LT(1500000000u, static_cast<unsigned int>(sb.st_ctime)); ++ EXPECT_LT(1500000000u, static_cast<unsigned int>(sb.st_atime_)); ++ EXPECT_LT(1500000000u, static_cast<unsigned int>(sb.st_mtime_)); ++ EXPECT_LT(1500000000u, static_cast<unsigned int>(sb.st_ctime_)); + } + } + +diff --git a/sandbox/linux/syscall_broker/remote_syscall_arg_handler_unittest.cc b/sandbox/linux/syscall_broker/remote_syscall_arg_handler_unittest.cc +index fffa9bb708..f517a9867c 100644 +--- a/sandbox/linux/syscall_broker/remote_syscall_arg_handler_unittest.cc ++++ b/sandbox/linux/syscall_broker/remote_syscall_arg_handler_unittest.cc +@@ -16,6 +16,7 @@ + #include "base/memory/page_size.h" + #include "base/posix/unix_domain_socket.h" + #include "base/test/bind.h" ++#include "sandbox/linux/tests/test_utils.h" + #include "sandbox/linux/tests/unit_tests.h" + #include "testing/gtest/include/gtest/gtest.h" + +@@ -52,19 +53,6 @@ void VerifyCorrectString(std::string str, size_t size) { + } + } + +-void* MapPagesOrDie(size_t num_pages) { +- void* addr = mmap(nullptr, num_pages * base::GetPageSize(), +- PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); +- PCHECK(addr); +- return addr; +-} +- +-void MprotectLastPageOrDie(char* addr, size_t num_pages) { +- size_t last_page_offset = (num_pages - 1) * base::GetPageSize(); +- PCHECK(mprotect(addr + last_page_offset, base::GetPageSize(), PROT_NONE) >= +- 0); +-} +- + pid_t ForkWaitingChild(base::OnceCallback<void(int)> + after_parent_signals_callback = base::DoNothing(), + base::ScopedFD* parent_sync_fd = nullptr) { +@@ -105,13 +93,13 @@ void ReadTest(const ReadTestConfig& test_config) { + size_t total_pages = (test_config.start_at + test_config.total_size + + base::GetPageSize() - 1) / + base::GetPageSize(); +- char* mmap_addr = static_cast<char*>(MapPagesOrDie(total_pages)); ++ char* mmap_addr = static_cast<char*>(TestUtils::MapPagesOrDie(total_pages)); + char* addr = mmap_addr + test_config.start_at; + FillBufferWithPath(addr, test_config.total_size, + test_config.include_null_byte); + + if (test_config.last_page_inaccessible) +- MprotectLastPageOrDie(mmap_addr, total_pages); ++ TestUtils::MprotectLastPageOrDie(mmap_addr, total_pages); + + pid_t pid = ForkWaitingChild(); + munmap(mmap_addr, base::GetPageSize() * total_pages); +@@ -212,7 +200,7 @@ SANDBOX_TEST(BrokerRemoteSyscallArgHandler, ReadChunkPlus1EndingOnePastPage) { + } + + SANDBOX_TEST(BrokerRemoteSyscallArgHandler, ReadChildExited) { +- void* addr = MapPagesOrDie(1); ++ void* addr = TestUtils::MapPagesOrDie(1); + FillBufferWithPath(static_cast<char*>(addr), strlen(kPathPart) + 1, true); + + base::ScopedFD parent_sync, child_sync; +@@ -240,10 +228,10 @@ SANDBOX_TEST(BrokerRemoteSyscallArgHandler, ReadChildExited) { + } + + SANDBOX_TEST(BrokerRemoteSyscallArgHandler, BasicWrite) { +- void* read_from = MapPagesOrDie(1); ++ void* read_from = TestUtils::MapPagesOrDie(1); + const size_t write_size = base::GetPageSize(); + FillBufferWithPath(static_cast<char*>(read_from), write_size, false); +- char* write_to = static_cast<char*>(MapPagesOrDie(1)); ++ char* write_to = static_cast<char*>(TestUtils::MapPagesOrDie(1)); + base::ScopedFD parent_signal_fd; + const std::vector<int> empty_fd_vec; + +@@ -278,8 +266,8 @@ SANDBOX_TEST(BrokerRemoteSyscallArgHandler, BasicWrite) { + } + + SANDBOX_TEST(BrokerRemoteSyscallArgHandler, WriteToInvalidAddress) { +- char* write_to = static_cast<char*>(MapPagesOrDie(1)); +- MprotectLastPageOrDie(write_to, 1); ++ char* write_to = static_cast<char*>(TestUtils::MapPagesOrDie(1)); ++ TestUtils::MprotectLastPageOrDie(write_to, 1); + base::ScopedFD parent_signal_fd; + const std::vector<int> empty_fd_vec; + +@@ -295,11 +283,11 @@ SANDBOX_TEST(BrokerRemoteSyscallArgHandler, WriteToInvalidAddress) { + } + + SANDBOX_TEST(BrokerRemoteSyscallArgHandler, WritePartiallyToInvalidAddress) { +- char* read_from = static_cast<char*>(MapPagesOrDie(2)); ++ char* read_from = static_cast<char*>(TestUtils::MapPagesOrDie(2)); + const size_t write_size = base::GetPageSize(); + FillBufferWithPath(static_cast<char*>(read_from), write_size, false); +- char* write_to = static_cast<char*>(MapPagesOrDie(2)); +- MprotectLastPageOrDie(write_to, 2); ++ char* write_to = static_cast<char*>(TestUtils::MapPagesOrDie(2)); ++ TestUtils::MprotectLastPageOrDie(write_to, 2); + write_to += base::GetPageSize() / 2; + base::ScopedFD parent_signal_fd; + const std::vector<int> empty_fd_vec; +@@ -314,7 +302,7 @@ SANDBOX_TEST(BrokerRemoteSyscallArgHandler, WritePartiallyToInvalidAddress) { + } + + SANDBOX_TEST(BrokerRemoteSyscallArgHandler, WriteChildExited) { +- char* addr = static_cast<char*>(MapPagesOrDie(1)); ++ char* addr = static_cast<char*>(TestUtils::MapPagesOrDie(1)); + FillBufferWithPath(static_cast<char*>(addr), strlen(kPathPart) + 1, true); + + base::ScopedFD parent_sync, child_sync; +diff --git a/sandbox/linux/syscall_broker/syscall_dispatcher.cc b/sandbox/linux/syscall_broker/syscall_dispatcher.cc +index b9ee93c14a..8a42397ef8 100644 +--- a/sandbox/linux/syscall_broker/syscall_dispatcher.cc ++++ b/sandbox/linux/syscall_broker/syscall_dispatcher.cc +@@ -19,8 +19,18 @@ namespace syscall_broker { + #define BROKER_UNPOISON_STRING(x) + #endif + ++int SyscallDispatcher::DefaultStatForTesting(const char* pathname, ++ bool follow_links, ++ default_stat_struct* sb) { ++#if defined(__NR_fstatat64) ++ return Stat64(pathname, follow_links, sb); ++#elif defined(__NR_newfstatat) ++ return Stat(pathname, follow_links, sb); ++#endif ++} ++ + int SyscallDispatcher::PerformStatat(const arch_seccomp_data& args, +- bool arch64) { ++ bool stat64) { + if (static_cast<int>(args.args[0]) != AT_FDCWD) + return -EPERM; + // Only allow the AT_SYMLINK_NOFOLLOW flag which is used by some libc +@@ -30,13 +40,29 @@ int SyscallDispatcher::PerformStatat(const arch_seccomp_data& args, + + const bool follow_links = + !(static_cast<int>(args.args[3]) & AT_SYMLINK_NOFOLLOW); +- if (arch64) { ++ if (stat64) { + return Stat64(reinterpret_cast<const char*>(args.args[1]), follow_links, +- reinterpret_cast<struct stat64*>(args.args[2])); ++ reinterpret_cast<struct kernel_stat64*>(args.args[2])); + } + + return Stat(reinterpret_cast<const char*>(args.args[1]), follow_links, +- reinterpret_cast<struct stat*>(args.args[2])); ++ reinterpret_cast<struct kernel_stat*>(args.args[2])); ++} ++ ++int SyscallDispatcher::PerformUnlinkat(const arch_seccomp_data& args) { ++ if (static_cast<int>(args.args[0]) != AT_FDCWD) ++ return -EPERM; ++ ++ int flags = static_cast<int>(args.args[2]); ++ ++ if (flags == AT_REMOVEDIR) { ++ return Rmdir(reinterpret_cast<const char*>(args.args[1])); ++ } ++ ++ if (flags != 0) ++ return -EPERM; ++ ++ return Unlink(reinterpret_cast<const char*>(args.args[1])); + } + + int SyscallDispatcher::DispatchSyscall(const arch_seccomp_data& args) { +@@ -127,59 +153,42 @@ int SyscallDispatcher::DispatchSyscall(const arch_seccomp_data& args) { + #if defined(__NR_stat) + case __NR_stat: + return Stat(reinterpret_cast<const char*>(args.args[0]), true, +- reinterpret_cast<struct stat*>(args.args[1])); ++ reinterpret_cast<struct kernel_stat*>(args.args[1])); + #endif + #if defined(__NR_stat64) + case __NR_stat64: + return Stat64(reinterpret_cast<const char*>(args.args[0]), true, +- reinterpret_cast<struct stat64*>(args.args[1])); ++ reinterpret_cast<struct kernel_stat64*>(args.args[1])); + #endif + #if defined(__NR_lstat) + case __NR_lstat: + // See https://crbug.com/847096 + BROKER_UNPOISON_STRING(reinterpret_cast<const char*>(args.args[0])); + return Stat(reinterpret_cast<const char*>(args.args[0]), false, +- reinterpret_cast<struct stat*>(args.args[1])); ++ reinterpret_cast<struct kernel_stat*>(args.args[1])); + #endif + #if defined(__NR_lstat64) + case __NR_lstat64: + // See https://crbug.com/847096 + BROKER_UNPOISON_STRING(reinterpret_cast<const char*>(args.args[0])); + return Stat64(reinterpret_cast<const char*>(args.args[0]), false, +- reinterpret_cast<struct stat64*>(args.args[1])); +-#endif +-#if defined(__NR_fstatat) +- case __NR_fstatat: +- return PerformStatat(args, /*arch64=*/false); ++ reinterpret_cast<struct kernel_stat64*>(args.args[1])); + #endif + #if defined(__NR_fstatat64) + case __NR_fstatat64: +- return PerformStatat(args, /*arch64=*/true); ++ return PerformStatat(args, /*stat64=*/true); + #endif + #if defined(__NR_newfstatat) + case __NR_newfstatat: +- return PerformStatat(args, /*arch64=*/false); ++ return PerformStatat(args, /*stat64=*/false); + #endif + #if defined(__NR_unlink) + case __NR_unlink: + return Unlink(reinterpret_cast<const char*>(args.args[0])); + #endif + #if defined(__NR_unlinkat) +- case __NR_unlinkat: { +- if (static_cast<int>(args.args[0]) != AT_FDCWD) +- return -EPERM; +- +- int flags = static_cast<int>(args.args[2]); +- +- if (flags == AT_REMOVEDIR) { +- return Rmdir(reinterpret_cast<const char*>(args.args[1])); +- } +- +- if (flags != 0) +- return -EPERM; +- +- return Unlink(reinterpret_cast<const char*>(args.args[1])); +- } ++ case __NR_unlinkat: ++ return PerformUnlinkat(args); + #endif // defined(__NR_unlinkat) + default: + RAW_CHECK(false); +diff --git a/sandbox/linux/syscall_broker/syscall_dispatcher.h b/sandbox/linux/syscall_broker/syscall_dispatcher.h +index d8b8874ad9..1d6653caf3 100644 +--- a/sandbox/linux/syscall_broker/syscall_dispatcher.h ++++ b/sandbox/linux/syscall_broker/syscall_dispatcher.h +@@ -9,13 +9,15 @@ + #include <cstddef> + + #include "sandbox/linux/system_headers/linux_seccomp.h" ++#include "sandbox/linux/system_headers/linux_stat.h" ++#include "sandbox/sandbox_export.h" + + namespace sandbox { + namespace syscall_broker { + + // An abstract class that defines all the system calls we perform for the + // sandboxed process. +-class SyscallDispatcher { ++class SANDBOX_EXPORT SyscallDispatcher { + public: + // Emulates access()/faccessat(). + // X_OK will always return an error in practice since the broker process +@@ -40,19 +42,34 @@ class SyscallDispatcher { + virtual int Rmdir(const char* path) const = 0; + + // Emulates stat()/stat64()/lstat()/lstat64()/fstatat()/newfstatat(). ++ // Stat64 is only available on 32-bit systems. + virtual int Stat(const char* pathname, + bool follow_links, +- struct stat* sb) const = 0; ++ struct kernel_stat* sb) const = 0; + virtual int Stat64(const char* pathname, + bool follow_links, +- struct stat64* sb) const = 0; ++ struct kernel_stat64* sb) const = 0; + + // Emulates unlink()/unlinkat(). + virtual int Unlink(const char* unlink) const = 0; + ++ // Different architectures use a different syscall from the stat family by ++ // default in glibc. E.g. 32-bit systems use *stat*64() and fill out struct ++ // kernel_stat64, whereas 64-bit systems use *stat*() and fill out struct ++ // kernel_stat. Some tests want to call the SyscallDispatcher directly, and ++ // should be using the default stat in order to test against glibc. ++ int DefaultStatForTesting(const char* pathname, ++ bool follow_links, ++ default_stat_struct* sb); ++ + // Validates the args passed to a *statat*() syscall and performs the syscall +- // using Stat() or Stat64(). +- int PerformStatat(const arch_seccomp_data& args, bool arch64); ++ // using Stat(), or on 32-bit systems it uses Stat64() for the *statat64() ++ // syscalls. ++ int PerformStatat(const arch_seccomp_data& args, bool stat64); ++ ++ // Validates the args passed to an unlinkat() syscall and performs the syscall ++ // using either Unlink() or Rmdir(). ++ int PerformUnlinkat(const arch_seccomp_data& args); + + // Reads the syscall number and arguments, imposes some policy (e.g. the *at() + // system calls must only allow AT_FDCWD as the first argument), and +diff --git a/sandbox/linux/system_headers/linux_stat.h b/sandbox/linux/system_headers/linux_stat.h +new file mode 100644 +index 0000000000..35788eb22a +--- /dev/null ++++ b/sandbox/linux/system_headers/linux_stat.h +@@ -0,0 +1,188 @@ ++// Copyright 2021 The Chromium Authors. All rights reserved. ++// Use of this source code is governed by a BSD-style license that can be ++// found in the LICENSE file. ++ ++#ifndef SANDBOX_LINUX_SYSTEM_HEADERS_LINUX_STAT_H_ ++#define SANDBOX_LINUX_SYSTEM_HEADERS_LINUX_STAT_H_ ++ ++#include <stdint.h> ++ ++#include "build/build_config.h" ++#include "sandbox/linux/system_headers/linux_syscalls.h" ++ ++#if defined(ARCH_CPU_MIPS_FAMILY) ++#if defined(ARCH_CPU_64_BITS) ++struct kernel_stat { ++#else ++struct kernel_stat64 { ++#endif ++ unsigned st_dev; ++ unsigned __pad0[3]; ++ unsigned long long st_ino; ++ unsigned st_mode; ++ unsigned st_nlink; ++ unsigned st_uid; ++ unsigned st_gid; ++ unsigned st_rdev; ++ unsigned __pad1[3]; ++ long long st_size; ++ unsigned st_atime_; ++ unsigned st_atime_nsec_; ++ unsigned st_mtime_; ++ unsigned st_mtime_nsec_; ++ unsigned st_ctime_; ++ unsigned st_ctime_nsec_; ++ unsigned st_blksize; ++ unsigned __pad2; ++ unsigned long long st_blocks; ++}; ++#else ++struct kernel_stat64 { ++ unsigned long long st_dev; ++ unsigned char __pad0[4]; ++ unsigned __st_ino; ++ unsigned st_mode; ++ unsigned st_nlink; ++ unsigned st_uid; ++ unsigned st_gid; ++ unsigned long long st_rdev; ++ unsigned char __pad3[4]; ++ long long st_size; ++ unsigned st_blksize; ++ unsigned long long st_blocks; ++ unsigned st_atime_; ++ unsigned st_atime_nsec_; ++ unsigned st_mtime_; ++ unsigned st_mtime_nsec_; ++ unsigned st_ctime_; ++ unsigned st_ctime_nsec_; ++ unsigned long long st_ino; ++}; ++#endif ++ ++#if defined(__i386__) || defined(__ARM_ARCH_3__) || defined(__ARM_EABI__) ++struct kernel_stat { ++ /* The kernel headers suggest that st_dev and st_rdev should be 32bit ++ * quantities encoding 12bit major and 20bit minor numbers in an interleaved ++ * format. In reality, we do not see useful data in the top bits. So, ++ * we'll leave the padding in here, until we find a better solution. ++ */ ++ unsigned short st_dev; ++ short pad1; ++ unsigned st_ino; ++ unsigned short st_mode; ++ unsigned short st_nlink; ++ unsigned short st_uid; ++ unsigned short st_gid; ++ unsigned short st_rdev; ++ short pad2; ++ unsigned st_size; ++ unsigned st_blksize; ++ unsigned st_blocks; ++ unsigned st_atime_; ++ unsigned st_atime_nsec_; ++ unsigned st_mtime_; ++ unsigned st_mtime_nsec_; ++ unsigned st_ctime_; ++ unsigned st_ctime_nsec_; ++ unsigned __unused4; ++ unsigned __unused5; ++}; ++#elif defined(__x86_64__) ++struct kernel_stat { ++ uint64_t st_dev; ++ uint64_t st_ino; ++ uint64_t st_nlink; ++ unsigned st_mode; ++ unsigned st_uid; ++ unsigned st_gid; ++ unsigned __pad0; ++ uint64_t st_rdev; ++ int64_t st_size; ++ int64_t st_blksize; ++ int64_t st_blocks; ++ uint64_t st_atime_; ++ uint64_t st_atime_nsec_; ++ uint64_t st_mtime_; ++ uint64_t st_mtime_nsec_; ++ uint64_t st_ctime_; ++ uint64_t st_ctime_nsec_; ++ int64_t __unused4[3]; ++}; ++#elif (defined(ARCH_CPU_MIPS_FAMILY) && defined(ARCH_CPU_32_BITS)) ++struct kernel_stat { ++ unsigned st_dev; ++ int st_pad1[3]; ++ unsigned st_ino; ++ unsigned st_mode; ++ unsigned st_nlink; ++ unsigned st_uid; ++ unsigned st_gid; ++ unsigned st_rdev; ++ int st_pad2[2]; ++ long st_size; ++ int st_pad3; ++ long st_atime_; ++ long st_atime_nsec_; ++ long st_mtime_; ++ long st_mtime_nsec_; ++ long st_ctime_; ++ long st_ctime_nsec_; ++ int st_blksize; ++ int st_blocks; ++ int st_pad4[14]; ++}; ++#elif defined(__aarch64__) ++struct kernel_stat { ++ unsigned long st_dev; ++ unsigned long st_ino; ++ unsigned int st_mode; ++ unsigned int st_nlink; ++ unsigned int st_uid; ++ unsigned int st_gid; ++ unsigned long st_rdev; ++ unsigned long __pad1; ++ long st_size; ++ int st_blksize; ++ int __pad2; ++ long st_blocks; ++ long st_atime_; ++ unsigned long st_atime_nsec_; ++ long st_mtime_; ++ unsigned long st_mtime_nsec_; ++ long st_ctime_; ++ unsigned long st_ctime_nsec_; ++ unsigned int __unused4; ++ unsigned int __unused5; ++}; ++#endif ++ ++// On 32-bit systems, we default to the 64-bit stat struct like libc ++// implementations do. Otherwise we default to the normal stat struct which is ++// already 64-bit. ++// These defines make it easy to call the right syscall to fill out a 64-bit ++// stat struct, which is the default in libc implementations but requires ++// different syscall names on 32 and 64-bit platforms. ++#if defined(__NR_fstatat64) ++ ++namespace sandbox { ++using default_stat_struct = struct kernel_stat64; ++} // namespace sandbox ++ ++#define __NR_fstatat_default __NR_fstatat64 ++#define __NR_fstat_default __NR_fstat64 ++ ++#elif defined(__NR_newfstatat) ++ ++namespace sandbox { ++using default_stat_struct = struct kernel_stat; ++} // namespace sandbox ++ ++#define __NR_fstatat_default __NR_newfstatat ++#define __NR_fstat_default __NR_fstat ++ ++#else ++#error "one of fstatat64 and newfstatat must be defined" ++#endif ++ ++#endif // SANDBOX_LINUX_SYSTEM_HEADERS_LINUX_STAT_H_ +diff --git a/sandbox/linux/system_headers/linux_time.h b/sandbox/linux/system_headers/linux_time.h +index 780f24dddd..f18c806611 100644 +--- a/sandbox/linux/system_headers/linux_time.h ++++ b/sandbox/linux/system_headers/linux_time.h +@@ -11,6 +11,32 @@ + #define CPUCLOCK_CLOCK_MASK 3 + #endif + ++#if !defined(CPUCLOCK_PROF) ++#define CPUCLOCK_PROF 0 ++#endif ++ ++#if !defined(CPUCLOCK_VIRT) ++#define CPUCLOCK_VIRT 1 ++#endif ++ ++#if !defined(CPUCLOCK_SCHED) ++#define CPUCLOCK_SCHED 2 ++#endif ++ ++#if !defined(CPUCLOCK_PERTHREAD_MASK) ++#define CPUCLOCK_PERTHREAD_MASK 4 ++#endif ++ ++#if !defined(MAKE_PROCESS_CPUCLOCK) ++#define MAKE_PROCESS_CPUCLOCK(pid, clock) \ ++ ((int)(~(unsigned)(pid) << 3) | (int)(clock)) ++#endif ++ ++#if !defined(MAKE_THREAD_CPUCLOCK) ++#define MAKE_THREAD_CPUCLOCK(tid, clock) \ ++ ((int)(~(unsigned)(tid) << 3) | (int)((clock) | CPUCLOCK_PERTHREAD_MASK)) ++#endif ++ + #if !defined(CLOCKFD) + #define CLOCKFD 3 + #endif +diff --git a/sandbox/linux/tests/test_utils.cc b/sandbox/linux/tests/test_utils.cc +index 847c20b20c..cf6041a4b4 100644 +--- a/sandbox/linux/tests/test_utils.cc ++++ b/sandbox/linux/tests/test_utils.cc +@@ -5,12 +5,14 @@ + #include "sandbox/linux/tests/test_utils.h" + + #include <errno.h> ++#include <sys/mman.h> + #include <sys/stat.h> + #include <sys/types.h> + #include <sys/wait.h> + #include <unistd.h> + + #include "base/check_op.h" ++#include "base/memory/page_size.h" + #include "base/posix/eintr_wrapper.h" + + namespace sandbox { +@@ -39,4 +41,17 @@ void TestUtils::HandlePostForkReturn(pid_t pid) { + } + } + ++void* TestUtils::MapPagesOrDie(size_t num_pages) { ++ void* addr = mmap(nullptr, num_pages * base::GetPageSize(), ++ PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); ++ PCHECK(addr); ++ return addr; ++} ++ ++void TestUtils::MprotectLastPageOrDie(char* addr, size_t num_pages) { ++ size_t last_page_offset = (num_pages - 1) * base::GetPageSize(); ++ PCHECK(mprotect(addr + last_page_offset, base::GetPageSize(), PROT_NONE) >= ++ 0); ++} ++ + } // namespace sandbox +diff --git a/sandbox/linux/tests/test_utils.h b/sandbox/linux/tests/test_utils.h +index 7cf9749fe4..43b028b1e3 100644 +--- a/sandbox/linux/tests/test_utils.h ++++ b/sandbox/linux/tests/test_utils.h +@@ -19,6 +19,8 @@ class TestUtils { + // makes sure that if fork() succeeded the child exits + // and the parent waits for it. + static void HandlePostForkReturn(pid_t pid); ++ static void* MapPagesOrDie(size_t num_pages); ++ static void MprotectLastPageOrDie(char* addr, size_t num_pages); + + private: + DISALLOW_IMPLICIT_CONSTRUCTORS(TestUtils); +diff --git a/sandbox/policy/linux/bpf_broker_policy_linux.cc b/sandbox/policy/linux/bpf_broker_policy_linux.cc +index 2963bb9ca8..6dc8c0581b 100644 +--- a/sandbox/policy/linux/bpf_broker_policy_linux.cc ++++ b/sandbox/policy/linux/bpf_broker_policy_linux.cc +@@ -93,8 +93,8 @@ ResultExpr BrokerProcessPolicy::EvaluateSyscall(int sysno) const { + return Allow(); + break; + #endif +-#if defined(__NR_fstatat) +- case __NR_fstatat: ++#if defined(__NR_fstatat64) ++ case __NR_fstatat64: + if (allowed_command_set_.test(syscall_broker::COMMAND_STAT)) + return Allow(); + break; |