// https://syzkaller.appspot.com/bug?id=5c9918d20f771265ad0ffae3c8f3859d24850692 // 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 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; } } #define SIZEOF_IO_URING_SQE 64 #define SIZEOF_IO_URING_CQE 16 #define SQ_HEAD_OFFSET 0 #define SQ_TAIL_OFFSET 64 #define SQ_RING_MASK_OFFSET 256 #define SQ_RING_ENTRIES_OFFSET 264 #define SQ_FLAGS_OFFSET 276 #define SQ_DROPPED_OFFSET 272 #define CQ_HEAD_OFFSET 128 #define CQ_TAIL_OFFSET 192 #define CQ_RING_MASK_OFFSET 260 #define CQ_RING_ENTRIES_OFFSET 268 #define CQ_RING_OVERFLOW_OFFSET 284 #define CQ_FLAGS_OFFSET 280 #define CQ_CQES_OFFSET 320 struct io_sqring_offsets { uint32_t head; uint32_t tail; uint32_t ring_mask; uint32_t ring_entries; uint32_t flags; uint32_t dropped; uint32_t array; uint32_t resv1; uint64_t resv2; }; struct io_cqring_offsets { uint32_t head; uint32_t tail; uint32_t ring_mask; uint32_t ring_entries; uint32_t overflow; uint32_t cqes; uint64_t resv[2]; }; struct io_uring_params { uint32_t sq_entries; uint32_t cq_entries; uint32_t flags; uint32_t sq_thread_cpu; uint32_t sq_thread_idle; uint32_t features; uint32_t resv[4]; struct io_sqring_offsets sq_off; struct io_cqring_offsets cq_off; }; #define IORING_OFF_SQ_RING 0 #define IORING_OFF_SQES 0x10000000ULL #define __NR_io_uring_setup 425 static long syz_io_uring_setup(volatile long a0, volatile long a1, volatile long a2, volatile long a3, volatile long a4, volatile long a5) { uint32_t entries = (uint32_t)a0; struct io_uring_params* setup_params = (struct io_uring_params*)a1; void* vma1 = (void*)a2; void* vma2 = (void*)a3; void** ring_ptr_out = (void**)a4; void** sqes_ptr_out = (void**)a5; uint32_t fd_io_uring = syscall(__NR_io_uring_setup, entries, setup_params); uint32_t sq_ring_sz = setup_params->sq_off.array + setup_params->sq_entries * sizeof(uint32_t); uint32_t cq_ring_sz = setup_params->cq_off.cqes + setup_params->cq_entries * SIZEOF_IO_URING_CQE; uint32_t ring_sz = sq_ring_sz > cq_ring_sz ? sq_ring_sz : cq_ring_sz; *ring_ptr_out = mmap(vma1, ring_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE | MAP_FIXED, fd_io_uring, IORING_OFF_SQ_RING); uint32_t sqes_sz = setup_params->sq_entries * SIZEOF_IO_URING_SQE; *sqes_ptr_out = mmap(vma2, sqes_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE | MAP_FIXED, fd_io_uring, IORING_OFF_SQES); return fd_io_uring; } static long syz_io_uring_submit(volatile long a0, volatile long a1, volatile long a2, volatile long a3) { char* ring_ptr = (char*)a0; char* sqes_ptr = (char*)a1; char* sqe = (char*)a2; uint32_t sqes_index = (uint32_t)a3; uint32_t sq_ring_entries = *(uint32_t*)(ring_ptr + SQ_RING_ENTRIES_OFFSET); uint32_t cq_ring_entries = *(uint32_t*)(ring_ptr + CQ_RING_ENTRIES_OFFSET); uint32_t sq_array_off = (CQ_CQES_OFFSET + cq_ring_entries * SIZEOF_IO_URING_CQE + 63) & ~63; if (sq_ring_entries) sqes_index %= sq_ring_entries; char* sqe_dest = sqes_ptr + sqes_index * SIZEOF_IO_URING_SQE; memcpy(sqe_dest, sqe, SIZEOF_IO_URING_SQE); uint32_t sq_ring_mask = *(uint32_t*)(ring_ptr + SQ_RING_MASK_OFFSET); uint32_t* sq_tail_ptr = (uint32_t*)(ring_ptr + SQ_TAIL_OFFSET); uint32_t sq_tail = *sq_tail_ptr & sq_ring_mask; uint32_t sq_tail_next = *sq_tail_ptr + 1; uint32_t* sq_array = (uint32_t*)(ring_ptr + sq_array_off); *(sq_array + sq_tail) = sqes_index; __atomic_store_n(sq_tail_ptr, sq_tail_next, __ATOMIC_RELEASE); return 0; } 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 { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } 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 loop(void) { int i, call, thread; int collide = 0; again: 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); if (collide && (call % 2) == 0) break; event_timedwait(&th->done, 45); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); if (!collide) { collide = 1; goto again; } } #ifndef __NR_io_uring_enter #define __NR_io_uring_enter 426 #endif uint64_t r[4] = {0xffffffffffffffff, 0x0, 0x0, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: *(uint32_t*)0x20000484 = 0; *(uint32_t*)0x20000488 = 0; *(uint32_t*)0x2000048c = 0; *(uint32_t*)0x20000490 = 0; *(uint32_t*)0x20000498 = -1; *(uint32_t*)0x2000049c = 0; *(uint32_t*)0x200004a0 = 0; *(uint32_t*)0x200004a4 = 0; res = -1; res = syz_io_uring_setup(0x6ad4, 0x20000480, 0x20ee7000, 0x20ffb000, 0x20000180, 0x20000040); if (res != -1) { r[0] = res; r[1] = *(uint64_t*)0x20000180; r[2] = *(uint64_t*)0x20000040; } break; case 1: res = -1; res = syz_open_dev(0xc, 4, 0x15); if (res != -1) r[3] = res; break; case 2: *(uint8_t*)0x20000000 = 6; *(uint8_t*)0x20000001 = 0; *(uint16_t*)0x20000002 = 0; *(uint32_t*)0x20000004 = r[3]; *(uint64_t*)0x20000008 = 0; *(uint64_t*)0x20000010 = 0; *(uint32_t*)0x20000018 = 0; *(uint16_t*)0x2000001c = 0; *(uint16_t*)0x2000001e = 0; *(uint64_t*)0x20000020 = 0; *(uint16_t*)0x20000028 = 0; *(uint16_t*)0x2000002a = 0; *(uint8_t*)0x2000002c = 0; *(uint8_t*)0x2000002d = 0; *(uint8_t*)0x2000002e = 0; *(uint8_t*)0x2000002f = 0; *(uint8_t*)0x20000030 = 0; *(uint8_t*)0x20000031 = 0; *(uint8_t*)0x20000032 = 0; *(uint8_t*)0x20000033 = 0; *(uint8_t*)0x20000034 = 0; *(uint8_t*)0x20000035 = 0; *(uint8_t*)0x20000036 = 0; *(uint8_t*)0x20000037 = 0; *(uint8_t*)0x20000038 = 0; *(uint8_t*)0x20000039 = 0; *(uint8_t*)0x2000003a = 0; *(uint8_t*)0x2000003b = 0; *(uint8_t*)0x2000003c = 0; *(uint8_t*)0x2000003d = 0; *(uint8_t*)0x2000003e = 0; *(uint8_t*)0x2000003f = 0; syz_io_uring_submit(r[1], r[2], 0x20000000, 0); break; case 3: syscall(__NR_io_uring_enter, r[0], 0x20450c, 0, 0ul, 0ul, 0ul); break; case 4: *(uint32_t*)0x20000080 = 0x7ff; *(uint32_t*)0x20000084 = 0x8b7; *(uint32_t*)0x20000088 = 3; *(uint32_t*)0x2000008c = 0x101; *(uint8_t*)0x20000090 = 9; memcpy((void*)0x20000091, "\xaf\x09\x01\xbc\xf9\xc6\xe4\x92\x86\x51\x7d\x7f" "\xbd\x43\x7d\x16\x69\x3e\x05", 19); syscall(__NR_ioctl, r[3], 0x5404, 0x20000080ul); 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); loop(); return 0; }