// https://syzkaller.appspot.com/bug?id=024b4f3d076f4b520b80b7affdb89a4c7c1797ff // 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 static struct { char* pos; int nesting; struct nlattr* nested[8]; char buf[1024]; } nlmsg; static void netlink_init(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(int typ, const void* data, int size) { struct nlattr* attr = (struct nlattr*)nlmsg.pos; attr->nla_len = sizeof(*attr) + size; attr->nla_type = typ; memcpy(attr + 1, data, size); nlmsg.pos += NLMSG_ALIGN(attr->nla_len); } static int netlink_send_ext(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 (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_send(int sock) { return netlink_send_ext(sock, 0, NULL); } const int kInitNetNsFd = 239; #define DEVLINK_FAMILY_NAME "devlink" #define DEVLINK_CMD_RELOAD 37 #define DEVLINK_ATTR_BUS_NAME 1 #define DEVLINK_ATTR_DEV_NAME 2 #define DEVLINK_ATTR_NETNS_FD 137 static void netlink_devlink_netns_move(const char* bus_name, const char* dev_name, int netns_fd) { struct genlmsghdr genlhdr; struct nlattr* attr; int sock, err, n; uint16_t id = 0; sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock == -1) exit(1); memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = CTRL_CMD_GETFAMILY; netlink_init(GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(CTRL_ATTR_FAMILY_NAME, DEVLINK_FAMILY_NAME, strlen(DEVLINK_FAMILY_NAME) + 1); err = netlink_send_ext(sock, GENL_ID_CTRL, &n); if (err) { goto error; } 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) { goto error; } recv(sock, nlmsg.buf, sizeof(nlmsg.buf), 0); /* recv ack */ memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = DEVLINK_CMD_RELOAD; netlink_init(id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1); netlink_attr(DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1); netlink_attr(DEVLINK_ATTR_NETNS_FD, &netns_fd, sizeof(netns_fd)); netlink_send(sock); error: close(sock); } static void initialize_devlink_pci(void) { int netns = open("/proc/self/ns/net", O_RDONLY); if (netns == -1) exit(1); int ret = setns(kInitNetNsFd, 0); if (ret == -1) exit(1); netlink_devlink_netns_move("pci", "0000:00:10.0", netns); ret = setns(netns, 0); if (ret == -1) exit(1); close(netns); } static long syz_open_procfs(volatile long a0, volatile long a1) { char buf[128]; memset(buf, 0, sizeof(buf)); if (a0 == 0) { snprintf(buf, sizeof(buf), "/proc/self/%s", (char*)a1); } else if (a0 == -1) { snprintf(buf, sizeof(buf), "/proc/thread-self/%s", (char*)a1); } else { snprintf(buf, sizeof(buf), "/proc/self/task/%d/%s", (int)a0, (char*)a1); } int fd = open(buf, O_RDWR); if (fd == -1) fd = open(buf, O_RDONLY); return fd; } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); intptr_t res = 0; res = syscall(__NR_socket, 0xa, 2, 0); if (res != -1) r[0] = res; memcpy((void*)0x20000440, "pagemap\000", 8); res = syz_open_procfs(0, 0x20000440); if (res != -1) r[1] = res; syscall(__NR_sendfile, r[0], r[1], 0, 0x100000206201); syscall(__NR_connect, -1, 0, 0); return 0; }