// https://syzkaller.appspot.com/bug?id=f9fb681614d4a44b0695d5da783bcaac92eb347e // 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 #include #include #include #include #include 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_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(...) \ ({ \ 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 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 bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } const int kInitNetNsFd = 201; static long syz_init_net_socket(volatile long domain, volatile long type, volatile long proto) { return syscall(__NR_socket, domain, type, proto); } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[1] = {0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // socket arguments: [ // domain: socket_domain = 0xa (8 bytes) // type: socket_type = 0x1 (8 bytes) // proto: int32 = 0x0 (4 bytes) // ] // returns sock syscall(__NR_socket, /*domain=AF_INET6*/ 0xaul, /*type=SOCK_STREAM*/ 1ul, /*proto=*/0); // syz_init_net_socket$x25 arguments: [ // domain: const = 0x9 (8 bytes) // type: const = 0x5 (8 bytes) // proto: const = 0x0 (8 bytes) // ] // returns sock_x25 res = -1; NONFAILING(res = syz_init_net_socket(/*domain=*/9, /*type=*/5, /*proto=*/0)); if (res != -1) r[0] = res; // ioctl arguments: [ // fd: fd (resource) // cmd: int32 = 0x890b (4 bytes) // arg: ptr[in, buffer] { // buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 // 6c 61 70 62 30} (length 0x19) // } // ] NONFAILING(memcpy((void*)0x200000000140, "\000\000\000\000\000\000\000\000\000\000\000\000\000\000" "\000\000\000\000\000\000lapb0", 25)); syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x890b, /*arg=*/0x200000000140ul); // bind$x25 arguments: [ // fd: sock_x25 (resource) // addr: ptr[in, sockaddr_x25] { // sockaddr_x25 { // sx25_family: const = 0x9 (2 bytes) // sx25_addr: union x25_address { // null: buffer: {20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 00} // (length 0x10) // } // } // } // addrlen: len = 0x12 (8 bytes) // ] NONFAILING(*(uint16_t*)0x200000000080 = 9); NONFAILING(memcpy((void*)0x200000000082, " \000", 16)); syscall(__NR_bind, /*fd=*/r[0], /*addr=*/0x200000000080ul, /*addrlen=*/0x12ul); // connect$x25 arguments: [ // fd: sock_x25 (resource) // addr: ptr[in, sockaddr_x25] { // sockaddr_x25 { // sx25_family: const = 0x9 (2 bytes) // sx25_addr: union x25_address { // remote: x25_address_remote { // prefix: buffer: {cc cc cc cc cc cc cc cc cc cc cc cc cc cc} // (length 0xe) id: proc = 0x0 (1 bytes) z: const = 0x0 (1 bytes) // } // } // } // } // addrlen: len = 0x12 (8 bytes) // ] NONFAILING(*(uint16_t*)0x200000000100 = 9); NONFAILING(memset((void*)0x200000000102, 204, 14)); NONFAILING(*(uint8_t*)0x200000000110 = 0x20); NONFAILING(*(uint8_t*)0x200000000111 = 0); syscall(__NR_connect, /*fd=*/r[0], /*addr=*/0x200000000100ul, /*addrlen=*/0x12ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; install_segv_handler(); loop(); return 0; }