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authornkozlovskiy <nmk@ydb.tech>2023-12-04 19:26:35 +0300
committernkozlovskiy <nmk@ydb.tech>2023-12-05 05:25:43 +0300
commite62474f851635573f9f6631039e113a02fd50179 (patch)
tree597d4bc8aad74ef42c55fd062398e93eceebfee3 /contrib/libs/clang16-rt/lib/gwp_asan/optional/segv_handler_posix.cpp
parente7eddec34be4f360877b46ffa2b70fde8a3a5b8f (diff)
downloadydb-e62474f851635573f9f6631039e113a02fd50179.tar.gz
ydb-oss sync: add clang16-rt/ to additionalPathsToCopy
Diffstat (limited to 'contrib/libs/clang16-rt/lib/gwp_asan/optional/segv_handler_posix.cpp')
-rw-r--r--contrib/libs/clang16-rt/lib/gwp_asan/optional/segv_handler_posix.cpp259
1 files changed, 259 insertions, 0 deletions
diff --git a/contrib/libs/clang16-rt/lib/gwp_asan/optional/segv_handler_posix.cpp b/contrib/libs/clang16-rt/lib/gwp_asan/optional/segv_handler_posix.cpp
new file mode 100644
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+++ b/contrib/libs/clang16-rt/lib/gwp_asan/optional/segv_handler_posix.cpp
@@ -0,0 +1,259 @@
+//===-- segv_handler_posix.cpp ----------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "gwp_asan/common.h"
+#include "gwp_asan/crash_handler.h"
+#include "gwp_asan/guarded_pool_allocator.h"
+#include "gwp_asan/optional/segv_handler.h"
+#include "gwp_asan/options.h"
+
+// RHEL creates the PRIu64 format macro (for printing uint64_t's) only when this
+// macro is defined before including <inttypes.h>.
+#ifndef __STDC_FORMAT_MACROS
+#define __STDC_FORMAT_MACROS 1
+#endif
+
+#include <assert.h>
+#include <inttypes.h>
+#include <signal.h>
+#include <stdio.h>
+
+using gwp_asan::AllocationMetadata;
+using gwp_asan::Error;
+using gwp_asan::GuardedPoolAllocator;
+using gwp_asan::Printf_t;
+using gwp_asan::backtrace::PrintBacktrace_t;
+using gwp_asan::backtrace::SegvBacktrace_t;
+
+namespace {
+
+struct ScopedEndOfReportDecorator {
+ ScopedEndOfReportDecorator(gwp_asan::Printf_t Printf) : Printf(Printf) {}
+ ~ScopedEndOfReportDecorator() { Printf("*** End GWP-ASan report ***\n"); }
+ gwp_asan::Printf_t Printf;
+};
+
+// Prints the provided error and metadata information.
+void printHeader(Error E, uintptr_t AccessPtr,
+ const gwp_asan::AllocationMetadata *Metadata,
+ Printf_t Printf) {
+ // Print using intermediate strings. Platforms like Android don't like when
+ // you print multiple times to the same line, as there may be a newline
+ // appended to a log file automatically per Printf() call.
+ constexpr size_t kDescriptionBufferLen = 128;
+ char DescriptionBuffer[kDescriptionBufferLen] = "";
+
+ bool AccessWasInBounds = false;
+ if (E != Error::UNKNOWN && Metadata != nullptr) {
+ uintptr_t Address = __gwp_asan_get_allocation_address(Metadata);
+ size_t Size = __gwp_asan_get_allocation_size(Metadata);
+ if (AccessPtr < Address) {
+ snprintf(DescriptionBuffer, kDescriptionBufferLen,
+ "(%zu byte%s to the left of a %zu-byte allocation at 0x%zx) ",
+ Address - AccessPtr, (Address - AccessPtr == 1) ? "" : "s", Size,
+ Address);
+ } else if (AccessPtr > Address) {
+ snprintf(DescriptionBuffer, kDescriptionBufferLen,
+ "(%zu byte%s to the right of a %zu-byte allocation at 0x%zx) ",
+ AccessPtr - Address, (AccessPtr - Address == 1) ? "" : "s", Size,
+ Address);
+ } else if (E == Error::DOUBLE_FREE) {
+ snprintf(DescriptionBuffer, kDescriptionBufferLen,
+ "(a %zu-byte allocation) ", Size);
+ } else {
+ AccessWasInBounds = true;
+ snprintf(DescriptionBuffer, kDescriptionBufferLen,
+ "(%zu byte%s into a %zu-byte allocation at 0x%zx) ",
+ AccessPtr - Address, (AccessPtr - Address == 1) ? "" : "s", Size,
+ Address);
+ }
+ }
+
+ // Possible number of digits of a 64-bit number: ceil(log10(2^64)) == 20. Add
+ // a null terminator, and round to the nearest 8-byte boundary.
+ uint64_t ThreadID = gwp_asan::getThreadID();
+ constexpr size_t kThreadBufferLen = 24;
+ char ThreadBuffer[kThreadBufferLen];
+ if (ThreadID == gwp_asan::kInvalidThreadID)
+ snprintf(ThreadBuffer, kThreadBufferLen, "<unknown>");
+ else
+ snprintf(ThreadBuffer, kThreadBufferLen, "%" PRIu64, ThreadID);
+
+ const char *OutOfBoundsAndUseAfterFreeWarning = "";
+ if (E == Error::USE_AFTER_FREE && !AccessWasInBounds) {
+ OutOfBoundsAndUseAfterFreeWarning =
+ " (warning: buffer overflow/underflow detected on a free()'d "
+ "allocation. This either means you have a buffer-overflow and a "
+ "use-after-free at the same time, or you have a long-lived "
+ "use-after-free bug where the allocation/deallocation metadata below "
+ "has already been overwritten and is likely bogus)";
+ }
+
+ Printf("%s%s at 0x%zx %sby thread %s here:\n", gwp_asan::ErrorToString(E),
+ OutOfBoundsAndUseAfterFreeWarning, AccessPtr, DescriptionBuffer,
+ ThreadBuffer);
+}
+
+void dumpReport(uintptr_t ErrorPtr, const gwp_asan::AllocatorState *State,
+ const gwp_asan::AllocationMetadata *Metadata,
+ SegvBacktrace_t SegvBacktrace, Printf_t Printf,
+ PrintBacktrace_t PrintBacktrace, void *Context) {
+ assert(State && "dumpReport missing Allocator State.");
+ assert(Metadata && "dumpReport missing Metadata.");
+ assert(Printf && "dumpReport missing Printf.");
+ assert(__gwp_asan_error_is_mine(State, ErrorPtr) &&
+ "dumpReport() called on a non-GWP-ASan error.");
+
+ uintptr_t InternalErrorPtr =
+ __gwp_asan_get_internal_crash_address(State, ErrorPtr);
+ if (InternalErrorPtr)
+ ErrorPtr = InternalErrorPtr;
+
+ const gwp_asan::AllocationMetadata *AllocMeta =
+ __gwp_asan_get_metadata(State, Metadata, ErrorPtr);
+
+ // It's unusual for a signal handler to be invoked multiple times for the same
+ // allocation, but it's possible in various scenarios, like:
+ // 1. A double-free or invalid-free was invoked in one thread at the same
+ // time as a buffer-overflow or use-after-free in another thread, or
+ // 2. Two threads do a use-after-free or buffer-overflow at the same time.
+ // In these instances, we've already dumped a report for this allocation, so
+ // skip dumping this issue as well.
+ if (AllocMeta->HasCrashed)
+ return;
+
+ Printf("*** GWP-ASan detected a memory error ***\n");
+ ScopedEndOfReportDecorator Decorator(Printf);
+
+ Error E = __gwp_asan_diagnose_error(State, Metadata, ErrorPtr);
+ if (E == Error::UNKNOWN) {
+ Printf("GWP-ASan cannot provide any more information about this error. "
+ "This may occur due to a wild memory access into the GWP-ASan pool, "
+ "or an overflow/underflow that is > 512B in length.\n");
+ return;
+ }
+
+ // Print the error header.
+ printHeader(E, ErrorPtr, AllocMeta, Printf);
+
+ // Print the fault backtrace.
+ static constexpr unsigned kMaximumStackFramesForCrashTrace = 512;
+ uintptr_t Trace[kMaximumStackFramesForCrashTrace];
+ size_t TraceLength =
+ SegvBacktrace(Trace, kMaximumStackFramesForCrashTrace, Context);
+
+ PrintBacktrace(Trace, TraceLength, Printf);
+
+ if (AllocMeta == nullptr)
+ return;
+
+ // Maybe print the deallocation trace.
+ if (__gwp_asan_is_deallocated(AllocMeta)) {
+ uint64_t ThreadID = __gwp_asan_get_deallocation_thread_id(AllocMeta);
+ if (ThreadID == gwp_asan::kInvalidThreadID)
+ Printf("0x%zx was deallocated by thread <unknown> here:\n", ErrorPtr);
+ else
+ Printf("0x%zx was deallocated by thread %zu here:\n", ErrorPtr, ThreadID);
+ TraceLength = __gwp_asan_get_deallocation_trace(
+ AllocMeta, Trace, kMaximumStackFramesForCrashTrace);
+ PrintBacktrace(Trace, TraceLength, Printf);
+ }
+
+ // Print the allocation trace.
+ uint64_t ThreadID = __gwp_asan_get_allocation_thread_id(AllocMeta);
+ if (ThreadID == gwp_asan::kInvalidThreadID)
+ Printf("0x%zx was allocated by thread <unknown> here:\n", ErrorPtr);
+ else
+ Printf("0x%zx was allocated by thread %zu here:\n", ErrorPtr, ThreadID);
+ TraceLength = __gwp_asan_get_allocation_trace(
+ AllocMeta, Trace, kMaximumStackFramesForCrashTrace);
+ PrintBacktrace(Trace, TraceLength, Printf);
+}
+
+struct sigaction PreviousHandler;
+bool SignalHandlerInstalled;
+bool RecoverableSignal;
+gwp_asan::GuardedPoolAllocator *GPAForSignalHandler;
+Printf_t PrintfForSignalHandler;
+PrintBacktrace_t PrintBacktraceForSignalHandler;
+SegvBacktrace_t BacktraceForSignalHandler;
+
+static void sigSegvHandler(int sig, siginfo_t *info, void *ucontext) {
+ const gwp_asan::AllocatorState *State =
+ GPAForSignalHandler->getAllocatorState();
+ void *FaultAddr = info->si_addr;
+ uintptr_t FaultAddrUPtr = reinterpret_cast<uintptr_t>(FaultAddr);
+
+ if (__gwp_asan_error_is_mine(State, FaultAddrUPtr)) {
+ GPAForSignalHandler->preCrashReport(FaultAddr);
+
+ dumpReport(FaultAddrUPtr, State, GPAForSignalHandler->getMetadataRegion(),
+ BacktraceForSignalHandler, PrintfForSignalHandler,
+ PrintBacktraceForSignalHandler, ucontext);
+
+ if (RecoverableSignal) {
+ GPAForSignalHandler->postCrashReportRecoverableOnly(FaultAddr);
+ return;
+ }
+ }
+
+ // Process any previous handlers as long as the crash wasn't a GWP-ASan crash
+ // in recoverable mode.
+ if (PreviousHandler.sa_flags & SA_SIGINFO) {
+ PreviousHandler.sa_sigaction(sig, info, ucontext);
+ } else if (PreviousHandler.sa_handler == SIG_DFL) {
+ // If the previous handler was the default handler, cause a core dump.
+ signal(SIGSEGV, SIG_DFL);
+ raise(SIGSEGV);
+ } else if (PreviousHandler.sa_handler == SIG_IGN) {
+ // If the previous segv handler was SIGIGN, crash iff we were responsible
+ // for the crash.
+ if (__gwp_asan_error_is_mine(GPAForSignalHandler->getAllocatorState(),
+ reinterpret_cast<uintptr_t>(info->si_addr))) {
+ signal(SIGSEGV, SIG_DFL);
+ raise(SIGSEGV);
+ }
+ } else {
+ PreviousHandler.sa_handler(sig);
+ }
+}
+} // anonymous namespace
+
+namespace gwp_asan {
+namespace segv_handler {
+
+void installSignalHandlers(gwp_asan::GuardedPoolAllocator *GPA, Printf_t Printf,
+ PrintBacktrace_t PrintBacktrace,
+ SegvBacktrace_t SegvBacktrace, bool Recoverable) {
+ assert(GPA && "GPA wasn't provided to installSignalHandlers.");
+ assert(Printf && "Printf wasn't provided to installSignalHandlers.");
+ assert(PrintBacktrace &&
+ "PrintBacktrace wasn't provided to installSignalHandlers.");
+ assert(SegvBacktrace &&
+ "SegvBacktrace wasn't provided to installSignalHandlers.");
+ GPAForSignalHandler = GPA;
+ PrintfForSignalHandler = Printf;
+ PrintBacktraceForSignalHandler = PrintBacktrace;
+ BacktraceForSignalHandler = SegvBacktrace;
+ RecoverableSignal = Recoverable;
+
+ struct sigaction Action = {};
+ Action.sa_sigaction = sigSegvHandler;
+ Action.sa_flags = SA_SIGINFO;
+ sigaction(SIGSEGV, &Action, &PreviousHandler);
+ SignalHandlerInstalled = true;
+}
+
+void uninstallSignalHandlers() {
+ if (SignalHandlerInstalled) {
+ sigaction(SIGSEGV, &PreviousHandler, nullptr);
+ SignalHandlerInstalled = false;
+ }
+}
+} // namespace segv_handler
+} // namespace gwp_asan