// RUN: %clang_esan_wset -O0 %s -o %t 2>&1 // RUN: %run %t 2>&1 | FileCheck %s #include <assert.h> #include <setjmp.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> sigjmp_buf mark; static void SignalHandler(int Sig) { if (Sig == SIGSEGV) { fprintf(stderr, "Handling SIGSEGV for signal\n"); siglongjmp(mark, 1); } exit(1); } static void SigactionHandler(int Sig, siginfo_t *Info, void *Ctx) { if (Sig == SIGSEGV) { fprintf(stderr, "Handling SIGSEGV for sigaction\n"); siglongjmp(mark, 1); } exit(1); } int main(int argc, char **argv) { __sighandler_t Prior = signal(SIGSEGV, SignalHandler); assert(Prior == SIG_DFL); if (sigsetjmp(mark, 1) == 0) *((volatile int *)(ssize_t)argc) = 42; // Raise SIGSEGV fprintf(stderr, "Past longjmp for signal\n"); Prior = signal(SIGSEGV, SIG_DFL); assert(Prior == SignalHandler); struct sigaction SigAct; SigAct.sa_sigaction = SigactionHandler; int Res = sigfillset(&SigAct.sa_mask); assert(Res == 0); SigAct.sa_flags = SA_SIGINFO; Res = sigaction(SIGSEGV, &SigAct, NULL); assert(Res == 0); if (sigsetjmp(mark, 1) == 0) *((volatile int *)(ssize_t)argc) = 42; // Raise SIGSEGV fprintf(stderr, "Past longjmp for sigaction\n"); Res = sigaction(SIGSEGV, NULL, &SigAct); assert(Res == 0); assert(SigAct.sa_sigaction == SigactionHandler); // Test blocking SIGSEGV and raising a shadow fault. sigset_t Set; sigemptyset(&Set); sigaddset(&Set, SIGSEGV); Res = sigprocmask(SIG_BLOCK, &Set, NULL); // Make a large enough mapping that its start point will be before any // prior library-region shadow access. char *buf = (char *)mmap(0, 640*1024, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); buf[0] = 4; munmap(buf, 640*1024); fprintf(stderr, "Past blocked-SIGSEGV shadow fault\n"); return 0; } // CHECK: Handling SIGSEGV for signal // CHECK-NEXT: Past longjmp for signal // CHECK-NEXT: Handling SIGSEGV for sigaction // CHECK-NEXT: Past longjmp for sigaction // CHECK-NEXT: Past blocked-SIGSEGV shadow fault // CHECK: {{.*}} EfficiencySanitizer: the total working set size: {{[0-9]+}} Bytes ({{[0-9][0-9]}} cache lines)