asan_posix.cc revision 303975
1295011Sandrew//===-- asan_posix.cc -----------------------------------------------------===// 2295011Sandrew// 3295011Sandrew// The LLVM Compiler Infrastructure 4295011Sandrew// 5295011Sandrew// This file is distributed under the University of Illinois Open Source 6295011Sandrew// License. See LICENSE.TXT for details. 7295011Sandrew// 8295011Sandrew//===----------------------------------------------------------------------===// 9295011Sandrew// 10295011Sandrew// This file is a part of AddressSanitizer, an address sanity checker. 11295011Sandrew// 12295011Sandrew// Posix-specific details. 13295011Sandrew//===----------------------------------------------------------------------===// 14295011Sandrew 15295011Sandrew#include "sanitizer_common/sanitizer_platform.h" 16295011Sandrew#if SANITIZER_POSIX 17295011Sandrew 18295011Sandrew#include "asan_internal.h" 19295011Sandrew#include "asan_interceptors.h" 20295011Sandrew#include "asan_mapping.h" 21295011Sandrew#include "asan_report.h" 22295011Sandrew#include "asan_stack.h" 23295011Sandrew#include "sanitizer_common/sanitizer_libc.h" 24295011Sandrew#include "sanitizer_common/sanitizer_posix.h" 25295011Sandrew#include "sanitizer_common/sanitizer_procmaps.h" 26295011Sandrew 27295011Sandrew#include <pthread.h> 28295011Sandrew#include <signal.h> 29295011Sandrew#include <stdlib.h> 30295011Sandrew#include <sys/time.h> 31295011Sandrew#include <sys/resource.h> 32295011Sandrew#include <unistd.h> 33295011Sandrew 34295011Sandrewnamespace __asan { 35295011Sandrew 36295011Sandrewvoid AsanOnDeadlySignal(int signo, void *siginfo, void *context) { 37295011Sandrew ScopedDeadlySignal signal_scope(GetCurrentThread()); 38295011Sandrew int code = (int)((siginfo_t*)siginfo)->si_code; 39295011Sandrew // Write the first message using the bullet-proof write. 40295011Sandrew if (18 != internal_write(2, "ASAN:DEADLYSIGNAL\n", 18)) Die(); 41295011Sandrew SignalContext sig = SignalContext::Create(siginfo, context); 42295011Sandrew 43295011Sandrew // Access at a reasonable offset above SP, or slightly below it (to account 44295011Sandrew // for x86_64 or PowerPC redzone, ARM push of multiple registers, etc) is 45295011Sandrew // probably a stack overflow. 46295011Sandrew bool IsStackAccess = sig.addr + 512 > sig.sp && sig.addr < sig.sp + 0xFFFF; 47295011Sandrew 48295011Sandrew#if __powerpc__ 49295011Sandrew // Large stack frames can be allocated with e.g. 50295011Sandrew // lis r0,-10000 51295011Sandrew // stdux r1,r1,r0 # store sp to [sp-10000] and update sp by -10000 52295011Sandrew // If the store faults then sp will not have been updated, so test above 53295011Sandrew // will not work, becase the fault address will be more than just "slightly" 54295011Sandrew // below sp. 55295011Sandrew if (!IsStackAccess && IsAccessibleMemoryRange(sig.pc, 4)) { 56295011Sandrew u32 inst = *(unsigned *)sig.pc; 57295011Sandrew u32 ra = (inst >> 16) & 0x1F; 58295011Sandrew u32 opcd = inst >> 26; 59295011Sandrew u32 xo = (inst >> 1) & 0x3FF; 60295011Sandrew // Check for store-with-update to sp. The instructions we accept are: 61295011Sandrew // stbu rs,d(ra) stbux rs,ra,rb 62295011Sandrew // sthu rs,d(ra) sthux rs,ra,rb 63295011Sandrew // stwu rs,d(ra) stwux rs,ra,rb 64295011Sandrew // stdu rs,ds(ra) stdux rs,ra,rb 65295011Sandrew // where ra is r1 (the stack pointer). 66295011Sandrew if (ra == 1 && 67295011Sandrew (opcd == 39 || opcd == 45 || opcd == 37 || opcd == 62 || 68295011Sandrew (opcd == 31 && (xo == 247 || xo == 439 || xo == 183 || xo == 181)))) 69295011Sandrew IsStackAccess = true; 70295011Sandrew } 71295011Sandrew#endif // __powerpc__ 72295011Sandrew 73295011Sandrew // We also check si_code to filter out SEGV caused by something else other 74295011Sandrew // then hitting the guard page or unmapped memory, like, for example, 75295011Sandrew // unaligned memory access. 76295011Sandrew if (IsStackAccess && (code == si_SEGV_MAPERR || code == si_SEGV_ACCERR)) 77295011Sandrew ReportStackOverflow(sig); 78295011Sandrew else if (signo == SIGFPE) 79295011Sandrew ReportDeadlySignal("FPE", sig); 80295011Sandrew else if (signo == SIGILL) 81295011Sandrew ReportDeadlySignal("ILL", sig); 82295011Sandrew else 83295011Sandrew ReportDeadlySignal("SEGV", sig); 84295011Sandrew} 85295011Sandrew 86295011Sandrew// ---------------------- TSD ---------------- {{{1 87295011Sandrew 88295011Sandrewstatic pthread_key_t tsd_key; 89295011Sandrewstatic bool tsd_key_inited = false; 90295011Sandrewvoid AsanTSDInit(void (*destructor)(void *tsd)) { 91295011Sandrew CHECK(!tsd_key_inited); 92295011Sandrew tsd_key_inited = true; 93295011Sandrew CHECK_EQ(0, pthread_key_create(&tsd_key, destructor)); 94295011Sandrew} 95295011Sandrew 96295011Sandrewvoid *AsanTSDGet() { 97295011Sandrew CHECK(tsd_key_inited); 98295011Sandrew return pthread_getspecific(tsd_key); 99295011Sandrew} 100295011Sandrew 101295011Sandrewvoid AsanTSDSet(void *tsd) { 102295011Sandrew CHECK(tsd_key_inited); 103295011Sandrew pthread_setspecific(tsd_key, tsd); 104295011Sandrew} 105295011Sandrew 106295011Sandrewvoid PlatformTSDDtor(void *tsd) { 107295011Sandrew AsanThreadContext *context = (AsanThreadContext*)tsd; 108295011Sandrew if (context->destructor_iterations > 1) { 109295011Sandrew context->destructor_iterations--; 110295011Sandrew CHECK_EQ(0, pthread_setspecific(tsd_key, tsd)); 111295011Sandrew return; 112295011Sandrew } 113295011Sandrew AsanThread::TSDDtor(tsd); 114295011Sandrew} 115295011Sandrew} // namespace __asan 116295011Sandrew 117295011Sandrew#endif // SANITIZER_POSIX 118295011Sandrew