// https://syzkaller.appspot.com/bug?id=293f48c6a63935b5872fac5eafff89a15518864e // 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 (__atomic_load_n(&running, __ATOMIC_RELAXED)) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } #ifndef __NR_bpf #define __NR_bpf 321 #endif uint64_t r[1] = {0xffffffffffffffff}; void execute_call(int call) { long res; switch (call) { case 0: syscall(__NR_socketpair, 0, 0, 2, 0x20000140); break; case 1: syscall(__NR_socket, 0xa, 1, 0); break; case 2: NONFAILING(*(uint32_t*)0x20000280 = 0x12); NONFAILING(*(uint32_t*)0x20000284 = 0); NONFAILING(*(uint32_t*)0x20000288 = 4); NONFAILING(*(uint32_t*)0x2000028c = 1); NONFAILING(*(uint32_t*)0x20000290 = 0); NONFAILING(*(uint32_t*)0x20000294 = 1); NONFAILING(*(uint32_t*)0x20000298 = 0); NONFAILING(*(uint8_t*)0x2000029c = 0); NONFAILING(*(uint8_t*)0x2000029d = 0); NONFAILING(*(uint8_t*)0x2000029e = 0); NONFAILING(*(uint8_t*)0x2000029f = 0); NONFAILING(*(uint8_t*)0x200002a0 = 0); NONFAILING(*(uint8_t*)0x200002a1 = 0); NONFAILING(*(uint8_t*)0x200002a2 = 0); NONFAILING(*(uint8_t*)0x200002a3 = 0); NONFAILING(*(uint8_t*)0x200002a4 = 0); NONFAILING(*(uint8_t*)0x200002a5 = 0); NONFAILING(*(uint8_t*)0x200002a6 = 0); NONFAILING(*(uint8_t*)0x200002a7 = 0); NONFAILING(*(uint8_t*)0x200002a8 = 0); NONFAILING(*(uint8_t*)0x200002a9 = 0); NONFAILING(*(uint8_t*)0x200002aa = 0); NONFAILING(*(uint8_t*)0x200002ab = 0); res = syscall(__NR_bpf, 0, 0x20000280, 0x2c); if (res != -1) r[0] = res; break; case 3: NONFAILING(*(uint32_t*)0x20000180 = r[0]); NONFAILING(*(uint64_t*)0x20000188 = 0x20000000); NONFAILING(*(uint64_t*)0x20000190 = 0x20000140); NONFAILING(*(uint64_t*)0x20000198 = 0); syscall(__NR_bpf, 2, 0x20000180, 0x20); break; case 4: NONFAILING(*(uint32_t*)0x20000180 = r[0]); NONFAILING(*(uint64_t*)0x20000188 = 0x20000080); NONFAILING(*(uint64_t*)0x20000190 = 0x20000140); NONFAILING(*(uint64_t*)0x20000198 = 0); syscall(__NR_bpf, 2, 0x20000180, 0x20); break; } } void execute_one() { execute(5); collide = 1; execute(5); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); install_segv_handler(); for (;;) { loop(); } }