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Diffstat (limited to 'test/syscalls/linux/shm.cc')
| -rw-r--r-- | test/syscalls/linux/shm.cc | 508 |
1 files changed, 0 insertions, 508 deletions
diff --git a/test/syscalls/linux/shm.cc b/test/syscalls/linux/shm.cc deleted file mode 100644 index 7ba752599..000000000 --- a/test/syscalls/linux/shm.cc +++ /dev/null @@ -1,508 +0,0 @@ -// 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 <stdio.h> -#include <sys/ipc.h> -#include <sys/mman.h> -#include <sys/shm.h> -#include <sys/types.h> - -#include "absl/time/clock.h" -#include "test/util/multiprocess_util.h" -#include "test/util/posix_error.h" -#include "test/util/temp_path.h" -#include "test/util/test_util.h" - -namespace gvisor { -namespace testing { -namespace { - -using ::testing::_; - -const uint64_t kAllocSize = kPageSize * 128ULL; - -PosixErrorOr<char*> Shmat(int shmid, const void* shmaddr, int shmflg) { - const intptr_t addr = - reinterpret_cast<intptr_t>(shmat(shmid, shmaddr, shmflg)); - if (addr == -1) { - return PosixError(errno, "shmat() failed"); - } - return reinterpret_cast<char*>(addr); -} - -PosixError Shmdt(const char* shmaddr) { - const int ret = shmdt(shmaddr); - if (ret == -1) { - return PosixError(errno, "shmdt() failed"); - } - return NoError(); -} - -template <typename T> -PosixErrorOr<int> Shmctl(int shmid, int cmd, T* buf) { - int ret = shmctl(shmid, cmd, reinterpret_cast<struct shmid_ds*>(buf)); - if (ret == -1) { - return PosixError(errno, "shmctl() failed"); - } - return ret; -} - -// ShmSegment is a RAII object for automatically cleaning up shm segments. -class ShmSegment { - public: - explicit ShmSegment(int id) : id_(id) {} - - ~ShmSegment() { - if (id_ >= 0) { - EXPECT_NO_ERRNO(Rmid()); - id_ = -1; - } - } - - ShmSegment(ShmSegment&& other) : id_(other.release()) {} - - ShmSegment& operator=(ShmSegment&& other) { - id_ = other.release(); - return *this; - } - - ShmSegment(ShmSegment const& other) = delete; - ShmSegment& operator=(ShmSegment const& other) = delete; - - int id() const { return id_; } - - int release() { - int id = id_; - id_ = -1; - return id; - } - - PosixErrorOr<int> Rmid() { - RETURN_IF_ERRNO(Shmctl<void>(id_, IPC_RMID, nullptr)); - return release(); - } - - private: - int id_ = -1; -}; - -PosixErrorOr<int> ShmgetRaw(key_t key, size_t size, int shmflg) { - int id = shmget(key, size, shmflg); - if (id == -1) { - return PosixError(errno, "shmget() failed"); - } - return id; -} - -PosixErrorOr<ShmSegment> Shmget(key_t key, size_t size, int shmflg) { - ASSIGN_OR_RETURN_ERRNO(int id, ShmgetRaw(key, size, shmflg)); - return ShmSegment(id); -} - -TEST(ShmTest, AttachDetach) { - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - struct shmid_ds attr; - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - EXPECT_EQ(attr.shm_segsz, kAllocSize); - EXPECT_EQ(attr.shm_nattch, 0); - - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - EXPECT_EQ(attr.shm_nattch, 1); - - const char* addr2 = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - EXPECT_EQ(attr.shm_nattch, 2); - - ASSERT_NO_ERRNO(Shmdt(addr)); - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - EXPECT_EQ(attr.shm_nattch, 1); - - ASSERT_NO_ERRNO(Shmdt(addr2)); - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - EXPECT_EQ(attr.shm_nattch, 0); -} - -TEST(ShmTest, LookupByKey) { - const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); - const key_t key = ftok(keyfile.path().c_str(), 1); - const ShmSegment shm = - ASSERT_NO_ERRNO_AND_VALUE(Shmget(key, kAllocSize, IPC_CREAT | 0777)); - const int id2 = ASSERT_NO_ERRNO_AND_VALUE(ShmgetRaw(key, kAllocSize, 0777)); - EXPECT_EQ(shm.id(), id2); -} - -TEST(ShmTest, DetachedSegmentsPersist) { - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - addr[0] = 'x'; - ASSERT_NO_ERRNO(Shmdt(addr)); - - // We should be able to re-attach to the same segment and get our data back. - addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - EXPECT_EQ(addr[0], 'x'); - ASSERT_NO_ERRNO(Shmdt(addr)); -} - -TEST(ShmTest, MultipleDetachFails) { - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - ASSERT_NO_ERRNO(Shmdt(addr)); - EXPECT_THAT(Shmdt(addr), PosixErrorIs(EINVAL, _)); -} - -TEST(ShmTest, IpcStat) { - const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); - const key_t key = ftok(keyfile.path().c_str(), 1); - - const time_t start = time(nullptr); - - const ShmSegment shm = - ASSERT_NO_ERRNO_AND_VALUE(Shmget(key, kAllocSize, IPC_CREAT | 0777)); - - const uid_t uid = getuid(); - const gid_t gid = getgid(); - const pid_t pid = getpid(); - - struct shmid_ds attr; - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - - EXPECT_EQ(attr.shm_perm.__key, key); - EXPECT_EQ(attr.shm_perm.uid, uid); - EXPECT_EQ(attr.shm_perm.gid, gid); - EXPECT_EQ(attr.shm_perm.cuid, uid); - EXPECT_EQ(attr.shm_perm.cgid, gid); - EXPECT_EQ(attr.shm_perm.mode, 0777); - - EXPECT_EQ(attr.shm_segsz, kAllocSize); - - EXPECT_EQ(attr.shm_atime, 0); - EXPECT_EQ(attr.shm_dtime, 0); - - // Change time is set on creation. - EXPECT_GE(attr.shm_ctime, start); - - EXPECT_EQ(attr.shm_cpid, pid); - EXPECT_EQ(attr.shm_lpid, 0); - - EXPECT_EQ(attr.shm_nattch, 0); - - // The timestamps only have a resolution of seconds; slow down so we actually - // see the timestamps change. - absl::SleepFor(absl::Seconds(1)); - const time_t pre_attach = time(nullptr); - - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - - EXPECT_GE(attr.shm_atime, pre_attach); - EXPECT_EQ(attr.shm_dtime, 0); - EXPECT_LT(attr.shm_ctime, pre_attach); - EXPECT_EQ(attr.shm_lpid, pid); - EXPECT_EQ(attr.shm_nattch, 1); - - absl::SleepFor(absl::Seconds(1)); - const time_t pre_detach = time(nullptr); - - ASSERT_NO_ERRNO(Shmdt(addr)); - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - - EXPECT_LT(attr.shm_atime, pre_detach); - EXPECT_GE(attr.shm_dtime, pre_detach); - EXPECT_LT(attr.shm_ctime, pre_detach); - EXPECT_EQ(attr.shm_lpid, pid); - EXPECT_EQ(attr.shm_nattch, 0); -} - -TEST(ShmTest, ShmStat) { - // This test relies on the segment we create to be the first one on the - // system, causing it to occupy slot 1. We can't reasonably expect this on a - // general Linux host. - SKIP_IF(!IsRunningOnGvisor()); - - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - struct shmid_ds attr; - ASSERT_NO_ERRNO(Shmctl(1, SHM_STAT, &attr)); - // This does the same thing as IPC_STAT, so only test that the syscall - // succeeds here. -} - -TEST(ShmTest, IpcInfo) { - struct shminfo info; - ASSERT_NO_ERRNO(Shmctl(0, IPC_INFO, &info)); - - EXPECT_EQ(info.shmmin, 1); // This is always 1, according to the man page. - EXPECT_GT(info.shmmax, info.shmmin); - EXPECT_GT(info.shmmni, 0); - EXPECT_GT(info.shmseg, 0); - EXPECT_GT(info.shmall, 0); -} - -TEST(ShmTest, ShmInfo) { - struct shm_info info; - - // We generally can't know what other processes on a linux machine - // does with shared memory segments, so we can't test specific - // numbers on Linux. When running under gvisor, we're guaranteed to - // be the only ones using shm, so we can easily verify machine-wide - // numbers. - if (IsRunningOnGvisor()) { - ASSERT_NO_ERRNO(Shmctl(0, SHM_INFO, &info)); - EXPECT_EQ(info.used_ids, 0); - EXPECT_EQ(info.shm_tot, 0); - EXPECT_EQ(info.shm_rss, 0); - EXPECT_EQ(info.shm_swp, 0); - } - - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - - ASSERT_NO_ERRNO(Shmctl(1, SHM_INFO, &info)); - - if (IsRunningOnGvisor()) { - ASSERT_NO_ERRNO(Shmctl(shm.id(), SHM_INFO, &info)); - EXPECT_EQ(info.used_ids, 1); - EXPECT_EQ(info.shm_tot, kAllocSize / kPageSize); - EXPECT_EQ(info.shm_rss, kAllocSize / kPageSize); - EXPECT_EQ(info.shm_swp, 0); // Gvisor currently never swaps. - } - - ASSERT_NO_ERRNO(Shmdt(addr)); -} - -TEST(ShmTest, ShmCtlSet) { - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - - struct shmid_ds attr; - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - ASSERT_EQ(attr.shm_perm.mode, 0777); - - attr.shm_perm.mode = 0766; - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_SET, &attr)); - - ASSERT_NO_ERRNO(Shmctl(shm.id(), IPC_STAT, &attr)); - ASSERT_EQ(attr.shm_perm.mode, 0766); - - ASSERT_NO_ERRNO(Shmdt(addr)); -} - -TEST(ShmTest, RemovedSegmentsAreMarkedDeleted) { - ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - const int id = ASSERT_NO_ERRNO_AND_VALUE(shm.Rmid()); - struct shmid_ds attr; - ASSERT_NO_ERRNO(Shmctl(id, IPC_STAT, &attr)); - EXPECT_NE(attr.shm_perm.mode & SHM_DEST, 0); - ASSERT_NO_ERRNO(Shmdt(addr)); -} - -TEST(ShmTest, RemovedSegmentsAreDestroyed) { - ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - - const uint64_t alloc_pages = kAllocSize / kPageSize; - - struct shm_info info; - ASSERT_NO_ERRNO(Shmctl(0 /*ignored*/, SHM_INFO, &info)); - const uint64_t before = info.shm_tot; - - ASSERT_NO_ERRNO(shm.Rmid()); - ASSERT_NO_ERRNO(Shmdt(addr)); - - ASSERT_NO_ERRNO(Shmctl(0 /*ignored*/, SHM_INFO, &info)); - if (IsRunningOnGvisor()) { - // No guarantees on system-wide shm memory usage on a generic linux host. - const uint64_t after = info.shm_tot; - EXPECT_EQ(after, before - alloc_pages); - } -} - -TEST(ShmTest, AllowsAttachToRemovedSegmentWithRefs) { - ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - const char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - const int id = ASSERT_NO_ERRNO_AND_VALUE(shm.Rmid()); - const char* addr2 = ASSERT_NO_ERRNO_AND_VALUE(Shmat(id, nullptr, 0)); - ASSERT_NO_ERRNO(Shmdt(addr)); - ASSERT_NO_ERRNO(Shmdt(addr2)); -} - -TEST(ShmTest, RemovedSegmentsAreNotDiscoverable) { - const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); - const key_t key = ftok(keyfile.path().c_str(), 1); - ShmSegment shm = - ASSERT_NO_ERRNO_AND_VALUE(Shmget(key, kAllocSize, IPC_CREAT | 0777)); - ASSERT_NO_ERRNO(shm.Rmid()); - EXPECT_THAT(Shmget(key, kAllocSize, 0777), PosixErrorIs(ENOENT, _)); -} - -TEST(ShmDeathTest, ReadonlySegment) { - SetupGvisorDeathTest(); - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, SHM_RDONLY)); - // Reading succeeds. - static_cast<void>(addr[0]); - // Writing fails. - EXPECT_EXIT(addr[0] = 'x', ::testing::KilledBySignal(SIGSEGV), ""); -} - -TEST(ShmDeathTest, SegmentNotAccessibleAfterDetach) { - // This test is susceptible to races with concurrent mmaps running in parallel - // gtest threads since the test relies on the address freed during a shm - // segment destruction to remain unused. We run the test body in a forked - // child to guarantee a single-threaded context to avoid this. - - SetupGvisorDeathTest(); - - const auto rest = [&] { - ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - - // Mark the segment as destroyed so it's automatically cleaned up when we - // crash below. We can't rely on the standard cleanup since the destructor - // will not run after the SIGSEGV. Note that this doesn't destroy the - // segment immediately since we're still attached to it. - ASSERT_NO_ERRNO(shm.Rmid()); - - addr[0] = 'x'; - ASSERT_NO_ERRNO(Shmdt(addr)); - - // This access should cause a SIGSEGV. - addr[0] = 'x'; - }; - - EXPECT_THAT(InForkedProcess(rest), - IsPosixErrorOkAndHolds(W_EXITCODE(0, SIGSEGV))); -} - -TEST(ShmTest, RequestingSegmentSmallerThanSHMMINFails) { - struct shminfo info; - ASSERT_NO_ERRNO(Shmctl(0, IPC_INFO, &info)); - const uint64_t size = info.shmmin - 1; - EXPECT_THAT(Shmget(IPC_PRIVATE, size, IPC_CREAT | 0777), - PosixErrorIs(EINVAL, _)); -} - -TEST(ShmTest, RequestingSegmentLargerThanSHMMAXFails) { - struct shminfo info; - ASSERT_NO_ERRNO(Shmctl(0, IPC_INFO, &info)); - const uint64_t size = info.shmmax + kPageSize; - EXPECT_THAT(Shmget(IPC_PRIVATE, size, IPC_CREAT | 0777), - PosixErrorIs(EINVAL, _)); -} - -TEST(ShmTest, RequestingUnalignedSizeSucceeds) { - EXPECT_NO_ERRNO(Shmget(IPC_PRIVATE, 4097, IPC_CREAT | 0777)); -} - -TEST(ShmTest, RequestingDuplicateCreationFails) { - const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); - const key_t key = ftok(keyfile.path().c_str(), 1); - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(key, kAllocSize, IPC_CREAT | IPC_EXCL | 0777)); - EXPECT_THAT(Shmget(key, kAllocSize, IPC_CREAT | IPC_EXCL | 0777), - PosixErrorIs(EEXIST, _)); -} - -TEST(ShmTest, NonExistentSegmentsAreNotFound) { - const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); - const key_t key = ftok(keyfile.path().c_str(), 1); - // Do not request creation. - EXPECT_THAT(Shmget(key, kAllocSize, 0777), PosixErrorIs(ENOENT, _)); -} - -TEST(ShmTest, SegmentsSizeFixedOnCreation) { - const TempPath keyfile = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); - const key_t key = ftok(keyfile.path().c_str(), 1); - - // Base segment. - const ShmSegment shm = - ASSERT_NO_ERRNO_AND_VALUE(Shmget(key, kAllocSize, IPC_CREAT | 0777)); - - // Ask for the same segment at half size. This succeeds. - const int id2 = - ASSERT_NO_ERRNO_AND_VALUE(ShmgetRaw(key, kAllocSize / 2, 0777)); - - // Ask for the same segment at double size. - EXPECT_THAT(Shmget(key, kAllocSize * 2, 0777), PosixErrorIs(EINVAL, _)); - - char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - char* addr2 = ASSERT_NO_ERRNO_AND_VALUE(Shmat(id2, nullptr, 0)); - - // We have 2 different maps... - EXPECT_NE(addr, addr2); - - // ... And both maps are kAllocSize bytes; despite asking for a half-sized - // segment for the second map. - addr[kAllocSize - 1] = 'x'; - addr2[kAllocSize - 1] = 'x'; - - ASSERT_NO_ERRNO(Shmdt(addr)); - ASSERT_NO_ERRNO(Shmdt(addr2)); -} - -TEST(ShmTest, PartialUnmap) { - const ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - EXPECT_THAT(munmap(addr + (kAllocSize / 4), kAllocSize / 2), - SyscallSucceeds()); - ASSERT_NO_ERRNO(Shmdt(addr)); -} - -// Check that sentry does not panic when asked for a zero-length private shm -// segment. -TEST(ShmTest, GracefullyFailOnZeroLenSegmentCreation) { - EXPECT_THAT(Shmget(IPC_PRIVATE, 0, 0), PosixErrorIs(EINVAL, _)); -} - -TEST(ShmTest, NoDestructionOfAttachedSegmentWithMultipleRmid) { - ShmSegment shm = ASSERT_NO_ERRNO_AND_VALUE( - Shmget(IPC_PRIVATE, kAllocSize, IPC_CREAT | 0777)); - char* addr = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - char* addr2 = ASSERT_NO_ERRNO_AND_VALUE(Shmat(shm.id(), nullptr, 0)); - - // There should be 2 refs to the segment from the 2 attachments, and a single - // self-reference. Mark the segment as destroyed more than 3 times through - // shmctl(RMID). If there's a bug with the ref counting, this should cause the - // count to drop to zero. - int id = shm.release(); - for (int i = 0; i < 6; ++i) { - ASSERT_NO_ERRNO(Shmctl<void>(id, IPC_RMID, nullptr)); - } - - // Segment should remain accessible. - addr[0] = 'x'; - ASSERT_NO_ERRNO(Shmdt(addr)); - - // Segment should remain accessible even after one of the two attachments are - // detached. - addr2[0] = 'x'; - ASSERT_NO_ERRNO(Shmdt(addr2)); -} - -} // namespace -} // namespace testing -} // namespace gvisor |