// https://syzkaller.appspot.com/bug?id=79a95578b90721ff58f3a8e5217fc28a0a36c963 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef SYS_getpid #define SYS_getpid 20 #endif #ifndef SYS_ktrace #define SYS_ktrace 45 #endif #ifndef SYS_mmap #define SYS_mmap 197 #endif #ifndef SYS_open #define SYS_open 5 #endif #ifndef SYS_sendmsg #define SYS_sendmsg 28 #endif #ifndef SYS_socketpair #define SYS_socketpair 135 #endif static unsigned long long procid; static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) static void kill_and_wait(int pid, int* status) { kill(pid, SIGKILL); while (waitpid(-1, status, 0) != pid) { } } static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void execute_one(void); #define WAIT_FLAGS 0 static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[2] = {0x0, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; NONFAILING(memcpy((void*)0x20000180, "./file0\000", 8)); syscall(SYS_open, /*file=*/0x20000180ul, /*flags=*/0x80000000000206ul, /*mode=*/0ul); res = syscall(SYS_getpid); if (res != -1) r[0] = res; NONFAILING(memcpy((void*)0x20000000, "./file0\000", 8)); syscall(SYS_ktrace, /*tracefile=*/0x20000000ul, /*ops=*/0ul, /*trpoints=*/0x40001d12ul, /*pid=*/r[0]); res = syscall(SYS_socketpair, /*domain=*/1ul, /*type=*/1ul, /*proto=*/0, /*fds=*/0x200001c0ul); if (res != -1) NONFAILING(r[1] = *(uint32_t*)0x200001c0); NONFAILING(*(uint64_t*)0x20000500 = 0); NONFAILING(*(uint32_t*)0x20000508 = 0); NONFAILING(*(uint64_t*)0x20000510 = 0); NONFAILING(*(uint64_t*)0x20000518 = 0); NONFAILING(*(uint64_t*)0x20000520 = 0x20000440); NONFAILING(*(uint64_t*)0x20000440 = 0); NONFAILING(*(uint32_t*)0x20000448 = 0xffff); NONFAILING(*(uint32_t*)0x2000044c = 2); NONFAILING(*(uint32_t*)0x20000450 = 0); NONFAILING(*(uint32_t*)0x20000454 = 0); NONFAILING(*(uint32_t*)0x20000458 = 0); NONFAILING(*(uint64_t*)0x20000460 = 0); NONFAILING(*(uint32_t*)0x20000468 = 0xffff); NONFAILING(*(uint32_t*)0x2000046c = 2); NONFAILING(*(uint32_t*)0x20000470 = 0); NONFAILING(*(uint32_t*)0x20000474 = 0); NONFAILING(*(uint32_t*)0x20000478 = 0); NONFAILING(*(uint64_t*)0x20000528 = 0x40); NONFAILING(*(uint32_t*)0x20000530 = 0); syscall(SYS_sendmsg, /*fd=*/r[1], /*msg=*/0x20000500ul, /*f=*/0ul); } int main(void) { syscall(SYS_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/3ul, /*flags=*/0x1012ul, /*fd=*/-1, /*pad=*/0ul, /*offset=*/0ul); install_segv_handler(); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }