// autogenerated by syzkaller (http://github.com/google/syzkaller) #ifndef __NR_listen #define __NR_listen 50 #endif #ifndef __NR_setsockopt #define __NR_setsockopt 54 #endif #ifndef __NR_connect #define __NR_connect 42 #endif #ifndef __NR_mmap #define __NR_mmap 9 #endif #ifndef __NR_socket #define __NR_socket 41 #endif #ifndef __NR_bind #define __NR_bind 49 #endif #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include const int kFailStatus = 67; const int kErrorStatus = 68; const int kRetryStatus = 69; __attribute__((noreturn)) void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } __attribute__((noreturn)) void fail(const char* msg, ...) { int e = errno; fflush(stdout); va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit(e == ENOMEM ? kRetryStatus : kFailStatus); } __attribute__((noreturn)) void exitf(const char* msg, ...) { int e = errno; fflush(stdout); va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit(kRetryStatus); } static int flag_debug; void debug(const char* msg, ...) { if (!flag_debug) return; va_list args; va_start(args, msg); vfprintf(stdout, msg, args); va_end(args); fflush(stdout); } __thread int skip_segv; __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)) { debug("SIGSEGV on %p, skipping\n", addr); _longjmp(segv_env, 1); } debug("SIGSEGV on %p, exiting\n", addr); doexit(sig); for (;;) { } } static void install_segv_handler() { 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(...) \ { \ __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); \ } #define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1) #define BITMASK_LEN_OFF(type, bf_off, bf_len) \ (type)(BITMASK_LEN(type, (bf_len)) << (bf_off)) #define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len) \ if ((bf_off) == 0 && (bf_len) == 0) { \ *(type*)(addr) = (type)(val); \ } else { \ type new_val = *(type*)(addr); \ new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len)); \ new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off); \ *(type*)(addr) = new_val; \ } static uintptr_t execute_syscall(int nr, uintptr_t a0, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintptr_t a4, uintptr_t a5, uintptr_t a6, uintptr_t a7, uintptr_t a8) { switch (nr) { default: return syscall(nr, a0, a1, a2, a3, a4, a5); } } static void setup_main_process() { 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); install_segv_handler(); char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_IO); } static int do_sandbox_none(int executor_pid, bool enable_tun) { int pid = fork(); if (pid) return pid; sandbox_common(); loop(); doexit(1); } static void remove_dir(const char* dir) { DIR* dp; struct dirent* ep; int iter = 0; retry: dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exitf("opendir(%s) failed due to NOFILE, exiting"); } exitf("opendir(%s) failed", dir); } while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); struct stat st; if (lstat(filename, &st)) exitf("lstat(%s) failed", filename); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { debug("unlink(%s)\n", filename); if (unlink(filename) == 0) break; if (errno == EROFS) { debug("ignoring EROFS\n"); break; } if (errno != EBUSY || i > 100) exitf("unlink(%s) failed", filename); debug("umount(%s)\n", filename); if (umount2(filename, MNT_DETACH)) exitf("umount(%s) failed", filename); } } closedir(dp); int i; for (i = 0;; i++) { debug("rmdir(%s)\n", dir); if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EROFS) { debug("ignoring EROFS\n"); break; } if (errno == EBUSY) { debug("umount(%s)\n", dir); if (umount2(dir, MNT_DETACH)) exitf("umount(%s) failed", dir); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exitf("rmdir(%s) failed", dir); } } static uint64_t current_time_ms() { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) fail("clock_gettime failed"); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void test(); void loop() { int iter; for (iter = 0;; iter++) { char cwdbuf[256]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) fail("failed to mkdir"); int pid = fork(); if (pid < 0) fail("clone failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); if (chdir(cwdbuf)) fail("failed to chdir"); test(); doexit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { int res = waitpid(-1, &status, __WALL | WNOHANG); if (res == pid) break; usleep(1000); if (current_time_ms() - start > 5 * 1000) { kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } remove_dir(cwdbuf); } } long r[25]; void* thr(void* arg) { switch ((long)arg) { case 0: r[0] = execute_syscall(__NR_mmap, 0x20000000ul, 0xe69000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul, 0, 0, 0); break; case 1: r[1] = execute_syscall(__NR_socket, 0xaul, 0x6ul, 0x0ul, 0, 0, 0, 0, 0, 0); break; case 2: r[2] = execute_syscall(__NR_socket, 0xaul, 0x6ul, 0x0ul, 0, 0, 0, 0, 0, 0); break; case 3: NONFAILING(*(uint16_t*)0x20e62fe0 = (uint16_t)0xa); NONFAILING(*(uint16_t*)0x20e62fe2 = (uint16_t)0x224e); NONFAILING(*(uint32_t*)0x20e62fe4 = (uint32_t)0x0); NONFAILING(*(uint64_t*)0x20e62fe8 = (uint64_t)0x0); NONFAILING(*(uint64_t*)0x20e62ff0 = (uint64_t)0x100000000000000); NONFAILING(*(uint32_t*)0x20e62ff8 = (uint32_t)0x0); r[9] = execute_syscall(__NR_bind, r[2], 0x20e62fe0ul, 0x20ul, 0, 0, 0, 0, 0, 0); break; case 4: r[10] = execute_syscall(__NR_listen, r[2], 0x5ul, 0, 0, 0, 0, 0, 0, 0); break; case 5: NONFAILING(*(uint16_t*)0x208c3000 = (uint16_t)0x1); NONFAILING(*(uint64_t*)0x208c3008 = (uint64_t)0x20c58000); NONFAILING(*(uint16_t*)0x20c58000 = (uint16_t)0x6); NONFAILING(*(uint8_t*)0x20c58002 = (uint8_t)0x3); NONFAILING(*(uint8_t*)0x20c58003 = (uint8_t)0xfe9); NONFAILING(*(uint32_t*)0x20c58004 = (uint32_t)0x6); r[17] = execute_syscall(__NR_setsockopt, r[2], 0x1ul, 0x1aul, 0x208c3000ul, 0x10ul, 0, 0, 0, 0); break; case 6: NONFAILING(*(uint16_t*)0x20e5afe0 = (uint16_t)0xa); NONFAILING(*(uint16_t*)0x20e5afe2 = (uint16_t)0x224e); NONFAILING(*(uint32_t*)0x20e5afe4 = (uint32_t)0x0); NONFAILING(*(uint64_t*)0x20e5afe8 = (uint64_t)0x0); NONFAILING(*(uint64_t*)0x20e5aff0 = (uint64_t)0x100000000000000); NONFAILING(*(uint32_t*)0x20e5aff8 = (uint32_t)0x0); r[24] = execute_syscall(__NR_connect, r[1], 0x20e5afe0ul, 0x20ul, 0, 0, 0, 0, 0, 0); break; } return 0; } void test() { long i; pthread_t th[14]; memset(r, -1, sizeof(r)); srand(getpid()); for (i = 0; i < 7; i++) { pthread_create(&th[i], 0, thr, (void*)i); usleep(10000); } usleep(100000); } int main() { int i; for (i = 0; i < 8; i++) { if (fork() == 0) { setup_main_process(); int pid = do_sandbox_none(i, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; } } sleep(1000000); return 0; }