diff options
Diffstat (limited to 'test/syscalls/linux/aio.cc')
-rw-r--r-- | test/syscalls/linux/aio.cc | 155 |
1 files changed, 73 insertions, 82 deletions
diff --git a/test/syscalls/linux/aio.cc b/test/syscalls/linux/aio.cc index 68dc05417..b27d4e10a 100644 --- a/test/syscalls/linux/aio.cc +++ b/test/syscalls/linux/aio.cc @@ -14,31 +14,57 @@ #include <fcntl.h> #include <linux/aio_abi.h> -#include <string.h> #include <sys/mman.h> #include <sys/syscall.h> #include <sys/types.h> #include <unistd.h> +#include <algorithm> +#include <string> + #include "gtest/gtest.h" #include "test/syscalls/linux/file_base.h" #include "test/util/cleanup.h" #include "test/util/file_descriptor.h" +#include "test/util/fs_util.h" +#include "test/util/memory_util.h" +#include "test/util/posix_error.h" +#include "test/util/proc_util.h" #include "test/util/temp_path.h" #include "test/util/test_util.h" +using ::testing::_; + namespace gvisor { namespace testing { namespace { +// Returns the size of the VMA containing the given address. +PosixErrorOr<size_t> VmaSizeAt(uintptr_t addr) { + ASSIGN_OR_RETURN_ERRNO(std::string proc_self_maps, + GetContents("/proc/self/maps")); + ASSIGN_OR_RETURN_ERRNO(auto entries, ParseProcMaps(proc_self_maps)); + // Use binary search to find the first VMA that might contain addr. + ProcMapsEntry target = {}; + target.end = addr; + auto it = + std::upper_bound(entries.begin(), entries.end(), target, + [](const ProcMapsEntry& x, const ProcMapsEntry& y) { + return x.end < y.end; + }); + // Check that it actually contains addr. + if (it == entries.end() || addr < it->start) { + return PosixError(ENOENT, absl::StrCat("no VMA contains address ", addr)); + } + return it->end - it->start; +} + constexpr char kData[] = "hello world!"; int SubmitCtx(aio_context_t ctx, long nr, struct iocb** iocbpp) { return syscall(__NR_io_submit, ctx, nr, iocbpp); } -} // namespace - class AIOTest : public FileTest { public: AIOTest() : ctx_(0) {} @@ -124,10 +150,10 @@ TEST_F(AIOTest, BasicWrite) { EXPECT_EQ(events[0].res, strlen(kData)); // Verify that the file contains the contents. - char verify_buf[32] = {}; - ASSERT_THAT(read(test_file_fd_.get(), &verify_buf[0], strlen(kData)), - SyscallSucceeds()); - EXPECT_EQ(strcmp(kData, &verify_buf[0]), 0); + char verify_buf[sizeof(kData)] = {}; + ASSERT_THAT(read(test_file_fd_.get(), verify_buf, sizeof(kData)), + SyscallSucceedsWithValue(strlen(kData))); + EXPECT_STREQ(verify_buf, kData); } TEST_F(AIOTest, BadWrite) { @@ -220,38 +246,25 @@ TEST_F(AIOTest, CloneVm) { TEST_F(AIOTest, Mremap) { // Setup a context that is 128 entries deep. ASSERT_THAT(SetupContext(128), SyscallSucceeds()); + const size_t ctx_size = + ASSERT_NO_ERRNO_AND_VALUE(VmaSizeAt(reinterpret_cast<uintptr_t>(ctx_))); struct iocb cb = CreateCallback(); struct iocb* cbs[1] = {&cb}; // Reserve address space for the mremap target so we have something safe to // map over. - // - // N.B. We reserve 2 pages because we'll attempt to remap to 2 pages below. - // That should fail with EFAULT, but will fail with EINVAL if this mmap - // returns the page immediately below ctx_, as - // [new_address, new_address+2*kPageSize) overlaps [ctx_, ctx_+kPageSize). - void* new_address = mmap(nullptr, 2 * kPageSize, PROT_READ, - MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - ASSERT_THAT(reinterpret_cast<intptr_t>(new_address), SyscallSucceeds()); - auto mmap_cleanup = Cleanup([new_address] { - EXPECT_THAT(munmap(new_address, 2 * kPageSize), SyscallSucceeds()); - }); - - // Test that remapping to a larger address fails. - void* res = mremap(reinterpret_cast<void*>(ctx_), kPageSize, 2 * kPageSize, - MREMAP_FIXED | MREMAP_MAYMOVE, new_address); - ASSERT_THAT(reinterpret_cast<intptr_t>(res), SyscallFailsWithErrno(EFAULT)); + Mapping dst = + ASSERT_NO_ERRNO_AND_VALUE(MmapAnon(ctx_size, PROT_READ, MAP_PRIVATE)); // Remap context 'handle' to a different address. - res = mremap(reinterpret_cast<void*>(ctx_), kPageSize, kPageSize, - MREMAP_FIXED | MREMAP_MAYMOVE, new_address); - ASSERT_THAT( - reinterpret_cast<intptr_t>(res), - SyscallSucceedsWithValue(reinterpret_cast<intptr_t>(new_address))); - mmap_cleanup.Release(); + ASSERT_THAT(Mremap(reinterpret_cast<void*>(ctx_), ctx_size, dst.len(), + MREMAP_FIXED | MREMAP_MAYMOVE, dst.ptr()), + IsPosixErrorOkAndHolds(dst.ptr())); aio_context_t old_ctx = ctx_; - ctx_ = reinterpret_cast<aio_context_t>(new_address); + ctx_ = reinterpret_cast<aio_context_t>(dst.addr()); + // io_destroy() will unmap dst now. + dst.release(); // Check that submitting the request with the old 'ctx_' fails. ASSERT_THAT(SubmitCtx(old_ctx, 1, cbs), SyscallFailsWithErrno(EINVAL)); @@ -260,18 +273,12 @@ TEST_F(AIOTest, Mremap) { ASSERT_THAT(Submit(1, cbs), SyscallSucceedsWithValue(1)); // Remap again. - new_address = - mmap(nullptr, kPageSize, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - ASSERT_THAT(reinterpret_cast<int64_t>(new_address), SyscallSucceeds()); - auto mmap_cleanup2 = Cleanup([new_address] { - EXPECT_THAT(munmap(new_address, kPageSize), SyscallSucceeds()); - }); - res = mremap(reinterpret_cast<void*>(ctx_), kPageSize, kPageSize, - MREMAP_FIXED | MREMAP_MAYMOVE, new_address); - ASSERT_THAT(reinterpret_cast<int64_t>(res), - SyscallSucceedsWithValue(reinterpret_cast<int64_t>(new_address))); - mmap_cleanup2.Release(); - ctx_ = reinterpret_cast<aio_context_t>(new_address); + dst = ASSERT_NO_ERRNO_AND_VALUE(MmapAnon(ctx_size, PROT_READ, MAP_PRIVATE)); + ASSERT_THAT(Mremap(reinterpret_cast<void*>(ctx_), ctx_size, dst.len(), + MREMAP_FIXED | MREMAP_MAYMOVE, dst.ptr()), + IsPosixErrorOkAndHolds(dst.ptr())); + ctx_ = reinterpret_cast<aio_context_t>(dst.addr()); + dst.release(); // Get the reply with yet another 'ctx_' and verify it. struct io_event events[1]; @@ -281,51 +288,33 @@ TEST_F(AIOTest, Mremap) { EXPECT_EQ(events[0].res, strlen(kData)); // Verify that the file contains the contents. - char verify_buf[32] = {}; - ASSERT_THAT(read(test_file_fd_.get(), &verify_buf[0], strlen(kData)), - SyscallSucceeds()); - EXPECT_EQ(strcmp(kData, &verify_buf[0]), 0); + char verify_buf[sizeof(kData)] = {}; + ASSERT_THAT(read(test_file_fd_.get(), verify_buf, sizeof(kData)), + SyscallSucceedsWithValue(strlen(kData))); + EXPECT_STREQ(verify_buf, kData); } -// Tests that AIO context can be replaced with a different mapping at the same -// address and continue working. Don't ask why, but Linux allows it. -TEST_F(AIOTest, MremapOver) { +// Tests that AIO context cannot be expanded with mremap. +TEST_F(AIOTest, MremapExpansion) { // Setup a context that is 128 entries deep. ASSERT_THAT(SetupContext(128), SyscallSucceeds()); + const size_t ctx_size = + ASSERT_NO_ERRNO_AND_VALUE(VmaSizeAt(reinterpret_cast<uintptr_t>(ctx_))); - struct iocb cb = CreateCallback(); - struct iocb* cbs[1] = {&cb}; - - ASSERT_THAT(Submit(1, cbs), SyscallSucceedsWithValue(1)); - - // Allocate a new VMA, copy 'ctx_' content over, and remap it on top - // of 'ctx_'. - void* new_address = mmap(nullptr, kPageSize, PROT_READ | PROT_WRITE, - MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); - ASSERT_THAT(reinterpret_cast<int64_t>(new_address), SyscallSucceeds()); - auto mmap_cleanup = Cleanup([new_address] { - EXPECT_THAT(munmap(new_address, kPageSize), SyscallSucceeds()); - }); - - memcpy(new_address, reinterpret_cast<void*>(ctx_), kPageSize); - void* res = - mremap(new_address, kPageSize, kPageSize, MREMAP_FIXED | MREMAP_MAYMOVE, - reinterpret_cast<void*>(ctx_)); - ASSERT_THAT(reinterpret_cast<int64_t>(res), SyscallSucceedsWithValue(ctx_)); - mmap_cleanup.Release(); - - // Everything continues to work just fine. - struct io_event events[1]; - ASSERT_THAT(GetEvents(1, 1, events, nullptr), SyscallSucceedsWithValue(1)); - EXPECT_EQ(events[0].data, 0x123); - EXPECT_EQ(events[0].obj, reinterpret_cast<long>(&cb)); - EXPECT_EQ(events[0].res, strlen(kData)); - - // Verify that the file contains the contents. - char verify_buf[32] = {}; - ASSERT_THAT(read(test_file_fd_.get(), &verify_buf[0], strlen(kData)), - SyscallSucceeds()); - EXPECT_EQ(strcmp(kData, &verify_buf[0]), 0); + // Reserve address space for the mremap target so we have something safe to + // map over. + Mapping dst = ASSERT_NO_ERRNO_AND_VALUE( + MmapAnon(ctx_size + kPageSize, PROT_NONE, MAP_PRIVATE)); + + // Test that remapping to a larger address range fails. + ASSERT_THAT(Mremap(reinterpret_cast<void*>(ctx_), ctx_size, dst.len(), + MREMAP_FIXED | MREMAP_MAYMOVE, dst.ptr()), + PosixErrorIs(EFAULT, _)); + + // mm/mremap.c:sys_mremap() => mremap_to() does do_munmap() of the destination + // before it hits the VM_DONTEXPAND check in vma_to_resize(), so we should no + // longer munmap it (another thread may have created a mapping there). + dst.release(); } // Tests that AIO calls fail if context's address is inaccessible. @@ -429,5 +418,7 @@ TEST_P(AIOVectorizedParamTest, BadIOVecs) { INSTANTIATE_TEST_SUITE_P(BadIOVecs, AIOVectorizedParamTest, ::testing::Values(IOCB_CMD_PREADV, IOCB_CMD_PWRITEV)); +} // namespace + } // namespace testing } // namespace gvisor |