// https://syzkaller.appspot.com/bug?id=0ff29101efe3523c886bd8b912945241a1c6b1b4 // 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 #include #include #include #include #include #include #include #include #include static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } struct nlmsg { char* pos; int nesting; struct nlattr* nested[8]; char buf[1024]; }; static struct nlmsg nlmsg; 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; 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 (hdr->nlmsg_type == NLMSG_DONE) { *reply_len = 0; 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_send(struct nlmsg* nlmsg, int sock) { return netlink_send_ext(nlmsg, sock, 0, NULL); } static int netlink_next_msg(struct nlmsg* nlmsg, unsigned int offset, unsigned int total_len) { struct nlmsghdr* hdr = (struct nlmsghdr*)(nlmsg->buf + offset); if (offset == total_len || offset + hdr->nlmsg_len > total_len) return -1; return hdr->nlmsg_len; } static void netlink_device_change(struct nlmsg* nlmsg, int sock, const char* name, bool up, const char* master, const void* mac, int macsize, const char* new_name) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; hdr.ifi_index = if_nametoindex(name); netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr)); if (new_name) netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name)); if (master) { int ifindex = if_nametoindex(master); netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex)); } if (macsize) netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize); int err = netlink_send(nlmsg, sock); (void)err; } const int kInitNetNsFd = 239; #define DEVLINK_FAMILY_NAME "devlink" #define DEVLINK_CMD_PORT_GET 5 #define DEVLINK_CMD_RELOAD 37 #define DEVLINK_ATTR_BUS_NAME 1 #define DEVLINK_ATTR_DEV_NAME 2 #define DEVLINK_ATTR_NETDEV_NAME 7 #define DEVLINK_ATTR_NETNS_FD 138 static int netlink_devlink_id_get(struct nlmsg* nlmsg, int sock) { struct genlmsghdr genlhdr; struct nlattr* attr; int err, n; uint16_t id = 0; 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, DEVLINK_FAMILY_NAME, strlen(DEVLINK_FAMILY_NAME) + 1); err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n); if (err) { return -1; } 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); /* recv ack */ return id; } static void netlink_devlink_netns_move(const char* bus_name, const char* dev_name, int netns_fd) { struct genlmsghdr genlhdr; int sock; int id, err; sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock == -1) exit(1); id = netlink_devlink_id_get(&nlmsg, sock); if (id == -1) goto error; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = DEVLINK_CMD_RELOAD; netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1); netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1); netlink_attr(&nlmsg, DEVLINK_ATTR_NETNS_FD, &netns_fd, sizeof(netns_fd)); err = netlink_send(&nlmsg, sock); if (err) { } error: close(sock); } static struct nlmsg nlmsg2; static void initialize_devlink_ports(const char* bus_name, const char* dev_name, const char* netdev_prefix) { struct genlmsghdr genlhdr; int len, total_len, id, err, offset; uint16_t netdev_index; int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock == -1) exit(1); int rtsock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (rtsock == -1) exit(1); id = netlink_devlink_id_get(&nlmsg, sock); if (id == -1) goto error; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = DEVLINK_CMD_PORT_GET; netlink_init(&nlmsg, id, NLM_F_DUMP, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1); netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1); err = netlink_send_ext(&nlmsg, sock, id, &total_len); if (err) { goto error; } offset = 0; netdev_index = 0; while ((len = netlink_next_msg(&nlmsg, offset, total_len)) != -1) { struct nlattr* attr = (struct nlattr*)(nlmsg.buf + offset + NLMSG_HDRLEN + NLMSG_ALIGN(sizeof(genlhdr))); for (; (char*)attr < nlmsg.buf + offset + len; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == DEVLINK_ATTR_NETDEV_NAME) { char* port_name; char netdev_name[IFNAMSIZ]; port_name = (char*)(attr + 1); snprintf(netdev_name, sizeof(netdev_name), "%s%d", netdev_prefix, netdev_index); netlink_device_change(&nlmsg2, rtsock, port_name, true, 0, 0, 0, netdev_name); break; } } offset += len; netdev_index++; } error: close(rtsock); 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); initialize_devlink_ports("pci", "0000:00:10.0", "netpci"); } #define MAX_FDS 30 static void setup_common() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); int netns = open("/proc/self/ns/net", O_RDONLY); if (netns == -1) exit(1); if (dup2(netns, kInitNetNsFd) < 0) exit(1); close(netns); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } initialize_devlink_pci(); loop(); exit(1); } static void close_fds() { int fd; for (fd = 3; fd < MAX_FDS; fd++) close(fd); } uint64_t r[1] = {0xffffffffffffffff}; void loop(void) { intptr_t res = 0; res = syscall(__NR_socket, 0x2000000000000021ul, 2ul, 2); if (res != -1) r[0] = res; *(uint16_t*)0x20000080 = 0x21; *(uint16_t*)0x20000082 = 0; *(uint16_t*)0x20000084 = 2; *(uint16_t*)0x20000086 = 0x10; *(uint16_t*)0x20000088 = 2; *(uint16_t*)0x2000008a = htobe16(0x4e24); *(uint8_t*)0x2000008c = 0xac; *(uint8_t*)0x2000008d = 0x14; *(uint8_t*)0x2000008e = 0x14; *(uint8_t*)0x2000008f = 0x1e; syscall(__NR_connect, r[0], 0x20000080ul, 0x24ul); *(uint64_t*)0x20005c00 = 0; *(uint32_t*)0x20005c08 = 0; *(uint64_t*)0x20005c10 = 0; *(uint64_t*)0x20005c18 = 0; *(uint64_t*)0x20005c20 = 0x20000340; memcpy( (void*)0x20000340, "\x18\x00\x00\x00\x00\x00\x00\x00\x10\x01\x00\x00\x01\x00\x00\x00\x77\x00" "\x46\xd9\x00\x00\x00\x00\x00\x00\xf4\x1b\x25\xe4\x06\xd5\x89\x37\xe7\xe8" "\x99\xe0\x52\x48\x2f\xc9\x57\x7f\x89\xf7\x1e\xbd\xdf\x07\x77\x98\xc1\xfb" "\x74\xed\x80\x23\xd1\x96\x26\x07\x4d\x27\xee\x6f\x22\x10\xb4\x7a\xb4\xa7" "\x69\x07\x47\x7a\x20\x95\x22\xad\xca\x7e\x54\xff\xb7\xde\xc9\xd9\xa6\xd8" "\x27\x3a\xcf\x83\x71\xac\x36\x19\x73\x05\xc0\x4a\x8c\xcf\xfc\xa5\x6c\xcb" "\xca\xbf\xb2\x5c\xc9\x46\x28\x34\x8a\x24\x59\x3c\x5d\xbd\xf2\x00\x79\x6a" "\x8f\xd2\x17\x36\x7c\x01\x7f\x76\xf1\x31\xc8\x69\x3a\xc4\x3b\x77\x47\x1b" "\xf2\x02\x60\xc6\x81\x33\xc3\x3f\x37\x5d\x17\x35\x0e\xe9\x14\x70\x7d\x2c" "\x35\x45\xb8\x12\xf7\xf5\x8f\x43\x67\x06\xf1\x7b\x26\xae\xba\xc8\xe1\xae" "\x91\x33\x79\x90\x24\x36\x61\x0c\x52\xb7\x24\x99\x31\x41\xa5\xcb\x7a\x0a" "\x9c\x3d\xca\x0a\x16\x78\x7a\x4d\x0c\x82\xe2\xd9\x82\x92\x19\xe3\xd9\x81" "\xd1\x96\xf1\xb7\x25\x6c\x49\xaa\xcd\x6b\x00\x00\x00\x00\x21\x50\xa4\x05" "\x8a\x8e\x43\x47\xe1\x3f\x94\xbe\x6d\x87\xfc\x7e\xcd\xaf\xb8\x8b\x1a\x5c" "\x00\x17\xa5\x35\x52\xe6\x79\x7c\x05\x61\x03\xb8\xd9\xe4\xea\xc3\xf0\x07" "\x65\x11\x65\x73\xf3\x80\xf6\xe7\x6a\xec\x10\x1f\xc9\x35\xc5\xc2\x5f\xac" "\xa1\x07\x1a\x96\xf3\xd5\xfd\xf7\xa8\xe7\xb9\x07\xd2\x36\xe9\x1a\x85\xb6" "\xe2\xa1\xb3\x31\xf2\x4a\x44\x92\xa2\x6a\x99\x4d\x04\xe3\xef\xed\x34\x9e" "\x81\xbc\x3b\x35\xcc\x53\x17\x78\x25\xfd\x34\x4c\x96\x8b\x8e\xaa\x41\xda" "\xa0\x14\x51\x1d\x5d\x1c\x05\x8a\x87\xe0\x01\xa4\xd1\xd6\xd4\x9d\xda\xba" "\x8c\x94\xe8\xc3\x9d\x69\x3d\x40\x1f\xa1\xcf\x52\x6e\xa5\x7d\x4d\x80\x66" "\x47\x5f\x49\x11\x0e\x67\x8c\x7e\xec\x10\xe2\x25\xe2\x34\x79\x89\xaf\x46" "\xcf\x48\x49\xc7\xab\x66\x64\x93\xd4\xd2\xc8\xc1\xe5\xf3\xc9\x7b\x06\x9e" "\x48\xfe\x79\x69\x86\xd2\x42\x90\x4f\x33\xe2\x84\xf6\x42\xbb\x7d\x14\x8c" "\x63\x4b\x77\xe3\x9b\x19\xea\xe2\xc2\x83\x1d\xad\xf0\xe6\x6a\x78\xf5\xdb" "\x7b\x39\x77\xb6\x08\xcc\xfd\x60\xa4\x27\x66\x85\x99\x79\x90\x23\xec\x7c" "\x56\x7e\x0b\xf7\xcd\x0d\x3a\xb4\x50\x0f\x0d\x0f\xcd\x95\x3d\xe8\xa7\x4a" "\xbe\x77\x15\x0f\x9b\x0f\xcf\x34\x72\xd1\x45\x1b\x09\x14\xf4\xa7\xb0\x04" "\xc5\x56\x2b\x9d\xc6\xd3\x7e\xd3\x12\x8e\xc4\xac\x4f\x2e\x3b\x58\x23\x80" "\x77\xb0\xbd\xe8\x74\xcc\xaf\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\xf3\xbf\x49\x7c\xba\xa2\xc0\xa1\x1f", 553); *(uint64_t*)0x20005c28 = 0x18; *(uint32_t*)0x20005c30 = 0; *(uint32_t*)0x20005c38 = 0; syscall(__NR_sendmmsg, r[0], 0x20005c00ul, 1ul, 0ul); close_fds(); } int main(void) { syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0); do_sandbox_none(); return 0; }