diff options
Diffstat (limited to 'lib/asan/asan_posix.cc')
-rw-r--r-- | lib/asan/asan_posix.cc | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/lib/asan/asan_posix.cc b/lib/asan/asan_posix.cc new file mode 100644 index 000000000000..061bb193034d --- /dev/null +++ b/lib/asan/asan_posix.cc @@ -0,0 +1,126 @@ +//===-- asan_linux.cc -----------------------------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file is a part of AddressSanitizer, an address sanity checker. +// +// Posix-specific details. +//===----------------------------------------------------------------------===// +#if defined(__linux__) || defined(__APPLE__) + +#include "asan_internal.h" +#include "asan_interceptors.h" +#include "asan_mapping.h" +#include "asan_stack.h" +#include "asan_thread_registry.h" +#include "sanitizer_common/sanitizer_libc.h" +#include "sanitizer_common/sanitizer_procmaps.h" + +#include <pthread.h> +#include <signal.h> +#include <stdlib.h> +#include <sys/time.h> +#include <sys/resource.h> +#include <unistd.h> + +static const uptr kAltStackSize = SIGSTKSZ * 4; // SIGSTKSZ is not enough. + +namespace __asan { + +static void MaybeInstallSigaction(int signum, + void (*handler)(int, siginfo_t *, void *)) { + if (!AsanInterceptsSignal(signum)) + return; + struct sigaction sigact; + REAL(memset)(&sigact, 0, sizeof(sigact)); + sigact.sa_sigaction = handler; + sigact.sa_flags = SA_SIGINFO; + if (flags()->use_sigaltstack) sigact.sa_flags |= SA_ONSTACK; + CHECK(0 == REAL(sigaction)(signum, &sigact, 0)); + if (flags()->verbosity >= 1) { + Report("Installed the sigaction for signal %d\n", signum); + } +} + +static void ASAN_OnSIGSEGV(int, siginfo_t *siginfo, void *context) { + uptr addr = (uptr)siginfo->si_addr; + // Write the first message using the bullet-proof write. + if (13 != internal_write(2, "ASAN:SIGSEGV\n", 13)) Die(); + uptr pc, sp, bp; + GetPcSpBp(context, &pc, &sp, &bp); + AsanReport("ERROR: AddressSanitizer crashed on unknown address %p" + " (pc %p sp %p bp %p T%d)\n", + (void*)addr, (void*)pc, (void*)sp, (void*)bp, + asanThreadRegistry().GetCurrentTidOrInvalid()); + AsanPrintf("AddressSanitizer can not provide additional info. ABORTING\n"); + GET_STACK_TRACE_WITH_PC_AND_BP(kStackTraceMax, pc, bp); + stack.PrintStack(); + ShowStatsAndAbort(); +} + +void SetAlternateSignalStack() { + stack_t altstack, oldstack; + CHECK(0 == sigaltstack(0, &oldstack)); + // If the alternate stack is already in place, do nothing. + if ((oldstack.ss_flags & SS_DISABLE) == 0) return; + // TODO(glider): the mapped stack should have the MAP_STACK flag in the + // future. It is not required by man 2 sigaltstack now (they're using + // malloc()). + void* base = MmapOrDie(kAltStackSize, __FUNCTION__); + altstack.ss_sp = base; + altstack.ss_flags = 0; + altstack.ss_size = kAltStackSize; + CHECK(0 == sigaltstack(&altstack, 0)); + if (flags()->verbosity > 0) { + Report("Alternative stack for T%d set: [%p,%p)\n", + asanThreadRegistry().GetCurrentTidOrInvalid(), + altstack.ss_sp, (char*)altstack.ss_sp + altstack.ss_size); + } +} + +void UnsetAlternateSignalStack() { + stack_t altstack, oldstack; + altstack.ss_sp = 0; + altstack.ss_flags = SS_DISABLE; + altstack.ss_size = 0; + CHECK(0 == sigaltstack(&altstack, &oldstack)); + UnmapOrDie(oldstack.ss_sp, oldstack.ss_size); +} + +void InstallSignalHandlers() { + // Set the alternate signal stack for the main thread. + // This will cause SetAlternateSignalStack to be called twice, but the stack + // will be actually set only once. + if (flags()->use_sigaltstack) SetAlternateSignalStack(); + MaybeInstallSigaction(SIGSEGV, ASAN_OnSIGSEGV); + MaybeInstallSigaction(SIGBUS, ASAN_OnSIGSEGV); +} + +// ---------------------- TSD ---------------- {{{1 + +static pthread_key_t tsd_key; +static bool tsd_key_inited = false; +void AsanTSDInit(void (*destructor)(void *tsd)) { + CHECK(!tsd_key_inited); + tsd_key_inited = true; + CHECK(0 == pthread_key_create(&tsd_key, destructor)); +} + +void *AsanTSDGet() { + CHECK(tsd_key_inited); + return pthread_getspecific(tsd_key); +} + +void AsanTSDSet(void *tsd) { + CHECK(tsd_key_inited); + pthread_setspecific(tsd_key, tsd); +} + +} // namespace __asan + +#endif // __linux__ || __APPLE_ |