// https://syzkaller.appspot.com/bug?id=e925f35f91b20fb565507134085b4d65824e5eb0 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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; \ } extern unsigned long long procid; struct fs_image_segment { void* data; uintptr_t size; uintptr_t offset; }; #define IMAGE_MAX_SEGMENTS 4096 #define IMAGE_MAX_SIZE (32 << 20) #define SYZ_memfd_create 319 static uintptr_t syz_mount_image(uintptr_t fs, uintptr_t dir, uintptr_t size, uintptr_t nsegs, uintptr_t segments, uintptr_t flags, uintptr_t opts) { char loopname[64]; int loopfd, err = 0, res = -1; uintptr_t i; struct fs_image_segment* segs = (struct fs_image_segment*)segments; if (nsegs > IMAGE_MAX_SEGMENTS) nsegs = IMAGE_MAX_SEGMENTS; for (i = 0; i < nsegs; i++) { if (segs[i].size > IMAGE_MAX_SIZE) segs[i].size = IMAGE_MAX_SIZE; segs[i].offset %= IMAGE_MAX_SIZE; if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size) segs[i].offset = IMAGE_MAX_SIZE - segs[i].size; if (size < segs[i].offset + segs[i].offset) size = segs[i].offset + segs[i].offset; } if (size > IMAGE_MAX_SIZE) size = IMAGE_MAX_SIZE; int memfd = syscall(SYZ_memfd_create, "syz_mount_image", 0); if (memfd == -1) { err = errno; goto error; } if (ftruncate(memfd, size)) { err = errno; goto error_close_memfd; } for (i = 0; i < nsegs; i++) { if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) { } } snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid); loopfd = open(loopname, O_RDWR); if (loopfd == -1) { err = errno; goto error_close_memfd; } if (ioctl(loopfd, LOOP_SET_FD, memfd)) { if (errno != EBUSY) { err = errno; goto error_close_loop; } ioctl(loopfd, LOOP_CLR_FD, 0); usleep(1000); if (ioctl(loopfd, LOOP_SET_FD, memfd)) { err = errno; goto error_close_loop; } } mkdir((char*)dir, 0777); if (strcmp((char*)fs, "iso9660") == 0) flags |= MS_RDONLY; if (mount(loopname, (char*)dir, (char*)fs, flags, (char*)opts)) { err = errno; goto error_clear_loop; } res = 0; error_clear_loop: ioctl(loopfd, LOOP_CLR_FD, 0); error_close_loop: close(loopfd); error_close_memfd: close(memfd); error: errno = err; return res; } static void execute_one(); extern unsigned long long procid; void loop() { while (1) { execute_one(); } } struct thread_t { int created, running, call; pthread_t th; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static int collide; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); } return 0; } static void execute(int num_calls) { int call, thread; running = 0; for (call = 0; call < num_calls; call++) { for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); pthread_create(&th->th, &attr, thr, th); } if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); if (collide && call % 2) break; struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (running) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; unsigned long long procid; void execute_call(int call) { long res; switch (call) { case 0: *(uint32_t*)0x2025c000 = 2; *(uint32_t*)0x2025c004 = 0x70; *(uint8_t*)0x2025c008 = 0xe3; *(uint8_t*)0x2025c009 = 0; *(uint8_t*)0x2025c00a = 0; *(uint8_t*)0x2025c00b = 0; *(uint32_t*)0x2025c00c = 0; *(uint64_t*)0x2025c010 = 0; *(uint64_t*)0x2025c018 = 0; *(uint64_t*)0x2025c020 = 0; STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 0, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 1, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 2, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 3, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 4, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 5, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 6, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 7, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 8, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 9, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 10, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 11, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 12, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 13, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 14, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 15, 2); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 17, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 18, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 19, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 20, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 21, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 22, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 23, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 24, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 25, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 26, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 27, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 28, 1); STORE_BY_BITMASK(uint64_t, 0x2025c028, 0, 29, 35); *(uint32_t*)0x2025c030 = 0; *(uint32_t*)0x2025c034 = 0; *(uint64_t*)0x2025c038 = 0x20000000; *(uint64_t*)0x2025c040 = 0; *(uint64_t*)0x2025c048 = 0; *(uint64_t*)0x2025c050 = 0; *(uint32_t*)0x2025c058 = 0; *(uint32_t*)0x2025c05c = 0; *(uint64_t*)0x2025c060 = 0; *(uint32_t*)0x2025c068 = 0; *(uint16_t*)0x2025c06c = 0; *(uint16_t*)0x2025c06e = 0; res = syscall(__NR_perf_event_open, 0x2025c000, 0, 0, -1, 0); if (res != -1) r[0] = res; break; case 1: syscall(__NR_ioctl, r[0], 0x4c06, r[0]); break; case 2: memcpy((void*)0x20000280, "./file0", 8); res = syscall(__NR_creat, 0x20000280, 0); if (res != -1) r[1] = res; break; case 3: *(uint32_t*)0x20000400 = 0x50; *(uint32_t*)0x20000404 = 1; *(uint64_t*)0x20000408 = 9; *(uint32_t*)0x20000410 = 7; *(uint32_t*)0x20000414 = 0x1a; *(uint32_t*)0x20000418 = 0xc75; *(uint32_t*)0x2000041c = 1; *(uint16_t*)0x20000420 = -1; *(uint16_t*)0x20000422 = 0xbe0d; *(uint32_t*)0x20000424 = 6; *(uint32_t*)0x20000428 = 7; *(uint32_t*)0x2000042c = 0; *(uint32_t*)0x20000430 = 0; *(uint32_t*)0x20000434 = 0; *(uint32_t*)0x20000438 = 0; *(uint32_t*)0x2000043c = 0; *(uint32_t*)0x20000440 = 0; *(uint32_t*)0x20000444 = 0; *(uint32_t*)0x20000448 = 0; *(uint32_t*)0x2000044c = 0; syscall(__NR_write, r[1], 0x20000400, 0x50); break; case 4: memcpy((void*)0x20000200, "msdos", 6); memcpy((void*)0x20000240, "./file0", 8); *(uint64_t*)0x20000380 = 0x200002c0; *(uint64_t*)0x20000388 = 0; *(uint64_t*)0x20000390 = 0x8000; memcpy((void*)0x200003c0, "errors=continue", 15); *(uint8_t*)0x200003cf = 0x2c; memcpy((void*)0x200003d0, "dos1xfloppy", 11); *(uint8_t*)0x200003db = 0x2c; memcpy((void*)0x200003dc, "umask", 5); *(uint8_t*)0x200003e1 = 0x3d; *(uint8_t*)0x200003e2 = 0x32; *(uint8_t*)0x200003e3 = 0x30; *(uint8_t*)0x200003e4 = 0x35; *(uint8_t*)0x200003e5 = 0x2c; memcpy((void*)0x200003e6, "errors=continue", 15); *(uint8_t*)0x200003f5 = 0x2c; *(uint8_t*)0x200003f6 = 0; syz_mount_image(0x20000200, 0x20000240, 0x7fff, 1, 0x20000380, 0x1000, 0x200003c0); break; case 5: memcpy((void*)0x20000040, "./file0", 8); memcpy((void*)0x20faffe7, "security.capability", 20); memcpy((void*)0x202b2fec, "\x00\x00\x00\x02\x01\x00\x00\x00\x00\x00\x00\x01" "\x04\x00\x00\x00\x00\x00\x00\x00", 20); syscall(__NR_lsetxattr, 0x20000040, 0x20faffe7, 0x202b2fec, 0x14, 0); break; } } void execute_one() { execute(6); collide = 1; execute(6); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (;;) { loop(); } }