// https://syzkaller.appspot.com/bug?id=dacc7707e9dc2ff70c53cb2ad92b4c675818ac68 // 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 #ifndef __NR_listen #define __NR_listen 201 #endif #ifndef __NR_mmap #define __NR_mmap 222 #endif #ifndef __NR_sendmsg #define __NR_sendmsg 211 #endif #ifndef __NR_socket #define __NR_socket 198 #endif 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; } 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, false); 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; res = syscall(__NR_socket, 0x2bul, 1ul, 0); if (res != -1) r[0] = res; syscall(__NR_listen, r[0], 0); res = syscall(__NR_socket, 0x10ul, 3ul, 0x10); if (res != -1) r[1] = res; memcpy((void*)0x20000000, "l2tp\000", 5); res = -1; res = syz_genetlink_get_family_id(0x20000000, -1); if (res != -1) r[2] = res; *(uint64_t*)0x20000240 = 0; *(uint32_t*)0x20000248 = 0; *(uint64_t*)0x20000250 = 0x20000100; *(uint64_t*)0x20000100 = 0x20000040; *(uint32_t*)0x20000040 = 0x3c; *(uint16_t*)0x20000044 = r[2]; *(uint16_t*)0x20000046 = 0x923; *(uint32_t*)0x20000048 = 0; *(uint32_t*)0x2000004c = 0; *(uint8_t*)0x20000050 = 1; *(uint8_t*)0x20000051 = 0; *(uint16_t*)0x20000052 = 0; *(uint16_t*)0x20000054 = 5; *(uint16_t*)0x20000056 = 7; *(uint8_t*)0x20000058 = 0; *(uint16_t*)0x2000005c = 8; *(uint16_t*)0x2000005e = 9; *(uint32_t*)0x20000060 = 0; *(uint16_t*)0x20000064 = 6; *(uint16_t*)0x20000066 = 2; *(uint16_t*)0x20000068 = 1; *(uint16_t*)0x2000006c = 8; *(uint16_t*)0x2000006e = 0xa; *(uint32_t*)0x20000070 = 0; *(uint16_t*)0x20000074 = 8; *(uint16_t*)0x20000076 = 0x17; *(uint32_t*)0x20000078 = -1; *(uint64_t*)0x20000108 = 0x3c; *(uint64_t*)0x20000258 = 1; *(uint64_t*)0x20000260 = 0; *(uint64_t*)0x20000268 = 0; *(uint32_t*)0x20000270 = 0; syscall(__NR_sendmsg, r[1], 0x20000240ul, 0ul); return 0; }