// https://syzkaller.appspot.com/bug?id=6dcd14a729df98f989c7b76d254226ae67084efd // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #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; \ } struct csum_inet { uint32_t acc; }; static void csum_inet_init(struct csum_inet* csum) { csum->acc = 0; } static void csum_inet_update(struct csum_inet* csum, const uint8_t* data, size_t length) { if (length == 0) return; size_t i; for (i = 0; i < length - 1; i += 2) csum->acc += *(uint16_t*)&data[i]; if (length & 1) csum->acc += (uint16_t)data[length - 1]; while (csum->acc > 0xffff) csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16); } static uint16_t csum_inet_digest(struct csum_inet* csum) { return ~csum->acc; } static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t 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)); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } uint64_t r[1] = {0xffffffffffffffff}; void loop() { long res; memcpy((void*)0x2063dff7, "/dev/sg#", 9); res = syz_open_dev(0x2063dff7, 0, 2); if (res != -1) r[0] = res; *(uint8_t*)0x20a2f000 = 0; *(uint8_t*)0x20a2f001 = 0; *(uint16_t*)0x20a2f002 = 0; *(uint16_t*)0x20a2f004 = 0; *(uint16_t*)0x20a2f006 = 0; *(uint16_t*)0x20a2f008 = 0; STORE_BY_BITMASK(uint8_t, 0x20a2f00a, 7, 0, 4); STORE_BY_BITMASK(uint8_t, 0x20a2f00a, 4, 4, 4); STORE_BY_BITMASK(uint8_t, 0x20a2f00b, 0, 0, 2); STORE_BY_BITMASK(uint8_t, 0x20a2f00b, 0, 2, 6); *(uint16_t*)0x20a2f00c = htobe16(0x30); *(uint16_t*)0x20a2f00e = htobe16(0); *(uint16_t*)0x20a2f010 = htobe16(0); *(uint8_t*)0x20a2f012 = 0; *(uint8_t*)0x20a2f013 = 0; *(uint16_t*)0x20a2f014 = 0; *(uint32_t*)0x20a2f016 = htobe32(0xe0000002); *(uint32_t*)0x20a2f01a = htobe32(0xe0000001); *(uint8_t*)0x20a2f01e = 1; *(uint8_t*)0x20a2f01f = 0x86; *(uint8_t*)0x20a2f020 = 6; *(uint32_t*)0x20a2f021 = htobe32(8); *(uint16_t*)0x20a2f026 = htobe16(0x4e20); *(uint16_t*)0x20a2f028 = htobe16(0x4e20); *(uint32_t*)0x20a2f02a = 0x42424242; *(uint32_t*)0x20a2f02e = 0x42424242; STORE_BY_BITMASK(uint8_t, 0x20a2f032, 0, 0, 1); STORE_BY_BITMASK(uint8_t, 0x20a2f032, 0, 1, 3); STORE_BY_BITMASK(uint8_t, 0x20a2f032, 5, 4, 4); *(uint8_t*)0x20a2f033 = 0; *(uint16_t*)0x20a2f034 = htobe16(0); *(uint16_t*)0x20a2f036 = 0; *(uint16_t*)0x20a2f038 = htobe16(0); struct csum_inet csum_1; csum_inet_init(&csum_1); csum_inet_update(&csum_1, (const uint8_t*)0x20a2f016, 4); csum_inet_update(&csum_1, (const uint8_t*)0x20a2f01a, 4); uint16_t csum_1_chunk_2 = 0x600; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 2); uint16_t csum_1_chunk_3 = 0x1400; csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 2); csum_inet_update(&csum_1, (const uint8_t*)0x20a2f026, 20); *(uint16_t*)0x20a2f036 = csum_inet_digest(&csum_1); struct csum_inet csum_2; csum_inet_init(&csum_2); csum_inet_update(&csum_2, (const uint8_t*)0x20a2f00a, 28); *(uint16_t*)0x20a2f014 = csum_inet_digest(&csum_2); syscall(__NR_write, r[0], 0x20a2f000, 0x3a); syscall(__NR_read, r[0], 0x20000080, 0x111); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); loop(); return 0; }