// https://syzkaller.appspot.com/bug?id=c27795ac8fc466e9b084f477cf784940a5cbcdc2 // 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 #include #include #include #include #include #include #include #include #include #include #include #include #include static unsigned long long procid; 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); } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) 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; } struct nlmsg { char* pos; int nesting; struct nlattr* nested[8]; char buf[4096]; }; static void netlink_init(struct nlmsg* nlmsg, int typ, int flags, const void* data, int size) { memset(nlmsg, 0, sizeof(*nlmsg)); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_type = typ; hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags; memcpy(hdr + 1, data, size); nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size); } static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data, int size) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_len = sizeof(*attr) + size; attr->nla_type = typ; if (size > 0) memcpy(attr + 1, data, size); nlmsg->pos += NLMSG_ALIGN(attr->nla_len); } static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type, int* reply_len, bool dofail) { if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting) exit(1); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_len = nlmsg->pos - nlmsg->buf; struct sockaddr_nl addr; memset(&addr, 0, sizeof(addr)); addr.nl_family = AF_NETLINK; ssize_t n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0, (struct sockaddr*)&addr, sizeof(addr)); if (n != (ssize_t)hdr->nlmsg_len) { if (dofail) exit(1); return -1; } n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); if (reply_len) *reply_len = 0; if (n < 0) { if (dofail) exit(1); return -1; } if (n < (ssize_t)sizeof(struct nlmsghdr)) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type == NLMSG_DONE) return 0; if (reply_len && hdr->nlmsg_type == reply_type) { *reply_len = n; return 0; } if (n < (ssize_t)(sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type != NLMSG_ERROR) { errno = EINVAL; if (dofail) exit(1); return -1; } errno = -((struct nlmsgerr*)(hdr + 1))->error; return -errno; } static int netlink_query_family_id(struct nlmsg* nlmsg, int sock, const char* family_name, bool dofail) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = CTRL_CMD_GETFAMILY; netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, family_name, strnlen(family_name, GENL_NAMSIZ - 1) + 1); int n = 0; int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n, dofail); if (err < 0) { return -1; } uint16_t id = 0; struct nlattr* attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN + NLMSG_ALIGN(sizeof(genlhdr))); for (; (char*)attr < nlmsg->buf + n; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == CTRL_ATTR_FAMILY_ID) { id = *(uint16_t*)(attr + 1); break; } } if (!id) { errno = EINVAL; return -1; } recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); return id; } const int kInitNetNsFd = 239; static long syz_init_net_socket(volatile long domain, volatile long type, volatile long proto) { return syscall(__NR_socket, domain, type, proto); } static long syz_genetlink_get_family_id(volatile long name, volatile long sock_arg) { bool dofail = false; int fd = sock_arg; if (fd < 0) { dofail = true; fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (fd == -1) { return -1; } } struct nlmsg nlmsg_tmp; int ret = netlink_query_family_id(&nlmsg_tmp, fd, (char*)name, dofail); if ((int)sock_arg < 0) close(fd); if (ret < 0) { return -1; } return ret; } 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) { int i, call, thread; for (call = 0; call < 5; 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); 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 (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) { continue; } kill_and_wait(pid, &status); break; } } } uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: res = -1; res = syz_init_net_socket(0x10, 3, 0x10); if (res != -1) r[0] = res; break; case 1: res = -1; res = syz_init_net_socket(0x10, 3, 0x10); if (res != -1) r[1] = res; break; case 2: memcpy((void*)0x200002c0, "nbd\000", 4); res = -1; res = syz_genetlink_get_family_id(0x200002c0, r[0]); if (res != -1) r[2] = res; break; case 3: res = syscall(__NR_openat, 0xffffffffffffff9cul, 0ul, 0ul, 0ul); if (res != -1) r[3] = res; break; case 4: *(uint64_t*)0x20000540 = 0; *(uint32_t*)0x20000548 = 0; *(uint64_t*)0x20000550 = 0x20000500; *(uint64_t*)0x20000500 = 0x20000400; *(uint32_t*)0x20000400 = 0xa8; *(uint16_t*)0x20000404 = r[2]; *(uint16_t*)0x20000406 = 1; *(uint32_t*)0x20000408 = 0; *(uint32_t*)0x2000040c = 0; *(uint8_t*)0x20000410 = 1; *(uint8_t*)0x20000411 = 0; *(uint16_t*)0x20000412 = 0; *(uint16_t*)0x20000414 = 0xc; *(uint16_t*)0x20000416 = 5; *(uint64_t*)0x20000418 = 0x102; *(uint16_t*)0x20000420 = 0xc; *(uint16_t*)0x20000422 = 2; *(uint64_t*)0x20000424 = 0; *(uint16_t*)0x2000042c = 0xc; STORE_BY_BITMASK(uint16_t, , 0x2000042e, 7, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x2000042f, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x2000042f, 1, 7, 1); *(uint16_t*)0x20000430 = 8; *(uint16_t*)0x20000432 = 1; *(uint32_t*)0x20000434 = -1; *(uint16_t*)0x20000438 = 0xc; *(uint16_t*)0x2000043a = 6; *(uint64_t*)0x2000043c = 1; *(uint16_t*)0x20000444 = 0xc; *(uint16_t*)0x20000446 = 8; *(uint64_t*)0x20000448 = 5; *(uint16_t*)0x20000450 = 0xc; *(uint16_t*)0x20000452 = 6; *(uint64_t*)0x20000454 = 1; *(uint16_t*)0x2000045c = 8; *(uint16_t*)0x2000045e = 1; *(uint32_t*)0x20000460 = 0 + procid * 1; *(uint16_t*)0x20000464 = 0x2c; STORE_BY_BITMASK(uint16_t, , 0x20000466, 7, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x20000467, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x20000467, 1, 7, 1); *(uint16_t*)0x20000468 = 8; *(uint16_t*)0x2000046a = 1; *(uint32_t*)0x2000046c = -1; *(uint16_t*)0x20000470 = 8; *(uint16_t*)0x20000472 = 1; *(uint32_t*)0x20000474 = -1; *(uint16_t*)0x20000478 = 8; *(uint16_t*)0x2000047a = 1; *(uint32_t*)0x2000047c = r[3]; *(uint16_t*)0x20000480 = 8; *(uint16_t*)0x20000482 = 1; *(uint32_t*)0x20000484 = -1; *(uint16_t*)0x20000488 = 8; *(uint16_t*)0x2000048a = 1; *(uint32_t*)0x2000048c = -1; *(uint16_t*)0x20000490 = 0xc; *(uint16_t*)0x20000492 = 2; *(uint64_t*)0x20000494 = 0x2000000; *(uint16_t*)0x2000049c = 0xc; *(uint16_t*)0x2000049e = 2; *(uint64_t*)0x200004a0 = 1; *(uint64_t*)0x20000508 = 0xa8; *(uint64_t*)0x20000558 = 1; *(uint64_t*)0x20000560 = 0; *(uint64_t*)0x20000568 = 0; *(uint32_t*)0x20000570 = 0x4801; syscall(__NR_sendmsg, r[1], 0x20000540ul, 0x80ul); break; } } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); for (procid = 0; procid < 6; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }