// https://syzkaller.appspot.com/bug?id=53475b9f7c745934a7c7efda058095c49491c747 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* uctx) { uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && (addr < prog_start || addr > prog_end)) { _longjmp(segv_env, 1); } doexit(sig); } static void install_segv_handler() { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); 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(...) \ { \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ } static void execute_one(); extern unsigned long long procid; void loop() { while (1) { execute_one(); } } struct thread_t { int created, running, call; pthread_t th; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static int collide; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); } return 0; } static void execute(int num_calls) { int call, thread; running = 0; for (call = 0; call < num_calls; call++) { for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); pthread_create(&th->th, &attr, thr, th); } if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); if (collide && call % 2) break; struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (running) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; unsigned long long procid; void execute_call(int call) { long res; switch (call) { case 0: res = syscall(__NR_socket, 0x26, 5, 0); if (res != -1) r[0] = res; break; case 1: NONFAILING(*(uint16_t*)0x201ca000 = 0x26); NONFAILING( memcpy((void*)0x201ca002, "\x61\x65\x61\x64\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 14)); NONFAILING(*(uint32_t*)0x201ca010 = 0); NONFAILING(*(uint32_t*)0x201ca014 = 0); NONFAILING(memcpy((void*)0x201ca018, "\x67\x63\x6d\x28\x73\x65\x72\x70\x65\x6e\x74\x2d\x67\x65" "\x6e\x65\x72\x69\x63\x29\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00", 64)); syscall(__NR_bind, r[0], 0x201ca000, 0x58); break; case 2: syscall(__NR_setsockopt, r[0], 0x117, 1, 0x204f7000, 0); break; case 3: res = syscall(__NR_dup, r[0]); if (res != -1) r[1] = res; break; case 4: res = syscall(__NR_accept4, r[1], 0, 0, 0x80800); if (res != -1) r[2] = res; break; case 5: NONFAILING(*(uint32_t*)0x20000180 = 0); syscall(__NR_setsockopt, r[1], 0x84, 0xd, 0x20000180, 4); break; case 6: NONFAILING(*(uint64_t*)0x200026c0 = 0x20000340); NONFAILING(*(uint32_t*)0x200026c8 = 0x80); NONFAILING(*(uint64_t*)0x200026d0 = 0x20000540); NONFAILING(*(uint64_t*)0x200026d8 = 0); NONFAILING(*(uint64_t*)0x200026e0 = 0x20000580); NONFAILING(*(uint64_t*)0x200026e8 = 0x1000); NONFAILING(*(uint32_t*)0x200026f0 = 0); NONFAILING(*(uint32_t*)0x200026f8 = 0); NONFAILING(*(uint64_t*)0x20002700 = 0x20001580); NONFAILING(*(uint32_t*)0x20002708 = 0x80); NONFAILING(*(uint64_t*)0x20002710 = 0x20002680); NONFAILING(*(uint64_t*)0x20002680 = 0x20001680); NONFAILING(*(uint64_t*)0x20002688 = 0x1000); NONFAILING(*(uint64_t*)0x20002718 = 1); NONFAILING(*(uint64_t*)0x20002720 = 0); NONFAILING(*(uint64_t*)0x20002728 = 0); NONFAILING(*(uint32_t*)0x20002730 = 0); NONFAILING(*(uint32_t*)0x20002738 = 0); NONFAILING(*(uint64_t*)0x20002740 = 0x77359400); NONFAILING(*(uint64_t*)0x20002748 = 0); syscall(__NR_recvmmsg, r[2], 0x200026c0, 2, 0, 0x20002740); break; case 7: NONFAILING(*(uint32_t*)0x20000080 = 0xfffffdd5); syscall(__NR_getpeername, r[1], 0x200001c0, 0x20000080); break; } } void execute_one() { execute(8); collide = 1; execute(8); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { install_segv_handler(); for (;;) { loop(); } } } sleep(1000000); return 0; }