// https://syzkaller.appspot.com/bug?id=7f375b63d8e49ecf9da041a3ee41557ede972141 // 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 #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)))) 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) { 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; unsigned n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0, (struct sockaddr*)&addr, sizeof(addr)); if (n != hdr->nlmsg_len) exit(1); n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); if (reply_len) *reply_len = 0; if (hdr->nlmsg_type == NLMSG_DONE) return 0; if (n < sizeof(struct nlmsghdr)) exit(1); if (reply_len && hdr->nlmsg_type == reply_type) { *reply_len = n; return 0; } if (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr)) exit(1); if (hdr->nlmsg_type != NLMSG_ERROR) exit(1); return ((struct nlmsgerr*)(hdr + 1))->error; } static int netlink_query_family_id(struct nlmsg* nlmsg, int sock, const char* family_name) { 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); 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) { return -1; } recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); return id; } const int kInitNetNsFd = 239; 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); } } 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) { int fd = sock_arg; if (fd < 0) { 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); if ((int)sock_arg >= 0) close(fd); if (ret < 0) { return -1; } return ret; } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0}; 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); intptr_t res = 0; memcpy((void*)0x20000080, "/dev/nbd#\000", 10); syz_open_dev(0x20000080, 0, 0); res = -1; res = syz_init_net_socket(0x10, 3, 0x10); if (res != -1) r[0] = res; res = -1; res = syz_init_net_socket(0x10, 3, 0x10); if (res != -1) r[1] = res; memcpy((void*)0x200000c0, "nbd\000", 4); res = -1; res = syz_genetlink_get_family_id(0x200000c0, r[1]); if (res != -1) r[2] = res; *(uint64_t*)0x20000240 = 0; *(uint32_t*)0x20000248 = 0; *(uint64_t*)0x20000250 = 0x20000200; *(uint64_t*)0x20000200 = 0x20000180; *(uint32_t*)0x20000180 = 0x48; *(uint16_t*)0x20000184 = r[2]; *(uint16_t*)0x20000186 = 1; *(uint32_t*)0x20000188 = 0x70bd26; *(uint32_t*)0x2000018c = 0x25dfdbfe; *(uint8_t*)0x20000190 = 2; *(uint8_t*)0x20000191 = 0; *(uint16_t*)0x20000192 = 0; *(uint16_t*)0x20000194 = 0x14; STORE_BY_BITMASK(uint16_t, , 0x20000196, 7, 0, 14); STORE_BY_BITMASK(uint16_t, , 0x20000197, 0, 6, 1); STORE_BY_BITMASK(uint16_t, , 0x20000197, 1, 7, 1); *(uint16_t*)0x20000198 = 8; *(uint16_t*)0x2000019a = 1; *(uint32_t*)0x2000019c = -1; *(uint16_t*)0x200001a0 = 8; *(uint16_t*)0x200001a2 = 1; *(uint32_t*)0x200001a4 = -1; *(uint16_t*)0x200001a8 = 8; *(uint16_t*)0x200001aa = 1; *(uint32_t*)0x200001ac = 0; *(uint16_t*)0x200001b0 = 0xc; *(uint16_t*)0x200001b2 = 5; *(uint64_t*)0x200001b4 = 0x2c; *(uint16_t*)0x200001bc = 0xc; *(uint16_t*)0x200001be = 8; *(uint64_t*)0x200001c0 = 6; *(uint64_t*)0x20000208 = 0x48; *(uint64_t*)0x20000258 = 1; *(uint64_t*)0x20000260 = 0; *(uint64_t*)0x20000268 = 0; *(uint32_t*)0x20000270 = 0x8041; syscall(__NR_sendmsg, r[0], 0x20000240ul, 0x4800ul); return 0; }