// https://syzkaller.appspot.com/bug?id=3ee8ab8cc5807204384954de2e9e6306591f0f7d // 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 #ifndef __NR_close_range #define __NR_close_range 436 #endif #ifndef __NR_seccomp #define __NR_seccomp 317 #endif 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 thread_start(void* (*fn)(void*), void* arg) { pthread_t th; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); int i = 0; for (; i < 100; i++) { if (pthread_create(&th, &attr, fn, arg) == 0) { pthread_attr_destroy(&attr); return; } if (errno == EAGAIN) { usleep(50); continue; } break; } exit(1); } typedef struct { int state; } event_t; static void event_init(event_t* ev) { ev->state = 0; } static void event_reset(event_t* ev) { ev->state = 0; } static void event_set(event_t* ev) { if (ev->state) exit(1); __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000); } static void event_wait(event_t* ev) { while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0); } static int event_isset(event_t* ev) { return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE); } static int event_timedwait(event_t* ev, uint64_t timeout) { uint64_t start = current_time_ms(); uint64_t now = start; for (;;) { uint64_t remain = timeout - (now - start); struct timespec ts; ts.tv_sec = remain / 1000; ts.tv_nsec = (remain % 1000) * 1000 * 1000; syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts); if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) return 1; now = current_time_ms(); if (now - start > timeout) return 0; } } 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; } static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { unsigned long nb = a1; char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(nb % 10); nb /= 10; } return open(buf, a2 & ~O_CREAT, 0); } } 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"); } struct thread_t { int created, call; event_t ready, done; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { event_wait(&th->ready); event_reset(&th->ready); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); event_set(&th->done); } return 0; } static void execute_one(void) { if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } int i, call, thread; for (call = 0; call < 7; call++) { for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; event_init(&th->ready); event_init(&th->done); event_set(&th->done); thread_start(thr, th); } if (!event_isset(&th->done)) continue; event_reset(&th->done); th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); event_set(&th->ready); if (call == 2) break; event_timedwait(&th->done, 50); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); } 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[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: // syz_open_dev$media arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 6d 65 64 69 61 23 00} (length 0xc) // } // id: intptr = 0x103 (8 bytes) // flags: open_flags = 0x0 (8 bytes) // ] // returns fd_media memcpy((void*)0x2000000000c0, "/dev/media#\000", 12); res = -1; res = syz_open_dev(/*dev=*/0x2000000000c0, /*id=*/0x103, /*flags=*/0); if (res != -1) r[0] = res; break; case 1: // socket$inet6_sctp arguments: [ // domain: const = 0xa (8 bytes) // type: sctp_socket_type = 0x5 (8 bytes) // proto: const = 0x84 (4 bytes) // ] // returns sock_sctp6 syscall(__NR_socket, /*domain=*/0xaul, /*type=SOCK_SEQPACKET*/ 5ul, /*proto=*/0x84); break; case 2: // ioctl$MEDIA_IOC_REQUEST_ALLOC arguments: [ // fd: fd_media (resource) // cmd: const = 0x80047c05 (4 bytes) // arg: nil // ] syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x80047c05, /*arg=*/0ul); for (int i = 0; i < 64; i++) { syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x80047c05, /*arg=*/0ul); } break; case 3: // seccomp$SECCOMP_SET_MODE_FILTER_LISTENER arguments: [ // op: const = 0x1 (8 bytes) // flags: seccomp_flags_listener = 0x0 (8 bytes) // arg: ptr[in, sock_fprog] { // sock_fprog { // len: len = 0x1 (2 bytes) // pad = 0x0 (6 bytes) // filter: ptr[in, array[sock_filter]] { // array[sock_filter] { // sock_filter { // code: int16 = 0x6 (2 bytes) // jt: int8 = 0x0 (1 bytes) // jf: int8 = 0x0 (1 bytes) // k: int32 = 0x7fffffff (4 bytes) // } // } // } // } // } // ] // returns fd_seccomp *(uint16_t*)0x200000000400 = 1; *(uint64_t*)0x200000000408 = 0x200000000380; *(uint16_t*)0x200000000380 = 6; *(uint8_t*)0x200000000382 = 0; *(uint8_t*)0x200000000383 = 0; *(uint32_t*)0x200000000384 = 0x7fffffff; res = syscall(__NR_seccomp, /*op=*/1ul, /*flags=*/0ul, /*arg=*/0x200000000400ul); if (res != -1) r[1] = res; break; case 4: // socket$unix arguments: [ // domain: const = 0x1 (8 bytes) // type: unix_socket_type = 0x5 (8 bytes) // proto: const = 0x0 (4 bytes) // ] // returns sock_unix res = syscall(__NR_socket, /*domain=*/1ul, /*type=SOCK_SEQPACKET*/ 5ul, /*proto=*/0); if (res != -1) r[2] = res; break; case 5: // dup2 arguments: [ // oldfd: fd (resource) // newfd: fd (resource) // ] // returns fd res = syscall(__NR_dup2, /*oldfd=*/r[2], /*newfd=*/r[1]); if (res != -1) r[3] = res; break; case 6: // close_range arguments: [ // fd: fd (resource) // max_fd: fd (resource) // flags: close_range_flags = 0x0 (8 bytes) // ] syscall(__NR_close_range, /*fd=*/r[3], /*max_fd=*/(intptr_t)-1, /*flags=*/0ul); break; } } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*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=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; loop(); return 0; }