// https://syzkaller.appspot.com/bug?id=12ead29884166e5196c2435d029aa748559f731b // 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 static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) 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 void netlink_nest(struct nlmsg* nlmsg, int typ) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_type = typ; nlmsg->pos += sizeof(*attr); nlmsg->nested[nlmsg->nesting++] = attr; } static void netlink_done(struct nlmsg* nlmsg) { struct nlattr* attr = nlmsg->nested[--nlmsg->nesting]; attr->nla_len = nlmsg->pos - (char*)attr; } 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_send(struct nlmsg* nlmsg, int sock) { return netlink_send_ext(nlmsg, sock, 0, NULL, true); } 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 void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type, const char* name, bool up) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); if (name) netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name)); netlink_nest(nlmsg, IFLA_LINKINFO); netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type)); } 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); if (err < 0) { } } static struct nlmsg nlmsg; 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 { unsigned long nb = a1; char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(nb % 10); nb /= 10; } return open(buf, a2, 0); } } #define NL802154_CMD_SET_SHORT_ADDR 11 #define NL802154_ATTR_IFINDEX 3 #define NL802154_ATTR_SHORT_ADDR 10 static const char* setup_802154() { const char* error = NULL; int sock_generic = -1; int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock_route == -1) { error = "socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE) failed"; goto fail; } sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock_generic == -1) { error = "socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC) failed"; goto fail; } { int nl802154_family_id = netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true); if (nl802154_family_id < 0) { error = "netlink_query_family_id failed"; goto fail; } for (int i = 0; i < 2; i++) { char devname[] = "wpan0"; devname[strlen(devname) - 1] += i; uint64_t hwaddr = 0xaaaaaaaaaaaa0002 + (i << 8); uint16_t shortaddr = 0xaaa0 + i; int ifindex = if_nametoindex(devname); struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = NL802154_CMD_SET_SHORT_ADDR; netlink_init(&nlmsg, nl802154_family_id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, NL802154_ATTR_IFINDEX, &ifindex, sizeof(ifindex)); netlink_attr(&nlmsg, NL802154_ATTR_SHORT_ADDR, &shortaddr, sizeof(shortaddr)); if (netlink_send(&nlmsg, sock_generic) < 0) { error = "NL802154_CMD_SET_SHORT_ADDR failed"; goto fail; } netlink_device_change(&nlmsg, sock_route, devname, true, 0, &hwaddr, sizeof(hwaddr), 0); if (i == 0) { netlink_add_device_impl(&nlmsg, "lowpan", "lowpan0", false); netlink_done(&nlmsg); netlink_attr(&nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); if (netlink_send(&nlmsg, sock_route) < 0) { error = "netlink: adding device lowpan0 type lowpan link wpan0"; goto fail; } } } } fail: close(sock_route); close(sock_generic); return error; } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; if ((reason = setup_802154())) printf("the reproducer may not work as expected: 802154 injection setup " "failed: %s\n", reason); install_segv_handler(); intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // openat$nullb arguments: [ // fd: const = 0xffffffffffffff9c (8 bytes) // file: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 6e 75 6c 6c 62 30 00} (length 0xc) // } // flags: open_flags = 0x2c240 (4 bytes) // mode: const = 0x0 (2 bytes) // ] // returns fd_block NONFAILING(memcpy((void*)0x200000000040, "/dev/nullb0\000", 12)); res = syscall( __NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x200000000040ul, /*flags=O_TRUNC|O_NOFOLLOW|O_LARGEFILE|O_DIRECT|O_CREAT*/ 0x2c240, /*mode=*/0); if (res != -1) r[0] = res; // syz_open_dev$loop arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 6c 6f 6f 70 23 00} (length 0xb) // } // id: intptr = 0x47ffffa (8 bytes) // flags: open_flags = 0x122c42 (8 bytes) // ] // returns fd_loop NONFAILING(memcpy((void*)0x200000000080, "/dev/loop#\000", 11)); res = -1; NONFAILING( res = syz_open_dev( /*dev=*/0x200000000080, /*id=*/0x47ffffa, /*flags=O_NONBLOCK|O_NOFOLLOW|O_CREAT|FASYNC|O_APPEND|0x100002*/ 0x122c42)); if (res != -1) r[1] = res; // ioctl$LOOP_CONFIGURE arguments: [ // fd: fd_loop (resource) // cmd: const = 0x4c0a (4 bytes) // arg: ptr[in, loop_config] { // loop_config { // fd: fd_loop (resource) // block_size: int32 = 0x0 (4 bytes) // info: loop_info64 { // lo_device: const = 0x0 (8 bytes) // lo_inode: const = 0x0 (8 bytes) // lo_rdevice: const = 0x0 (8 bytes) // lo_offset: int64 = 0x8 (8 bytes) // lo_sizelimit: int64 = 0x0 (8 bytes) // lo_number: const = 0x0 (4 bytes) // lo_enc_type: lo_encrypt_type = 0x0 (4 bytes) // lo_enc_key_size: int32 = 0x13 (4 bytes) // lo_flags: lo_flags = 0x1c (4 bytes) // lo_file_name: buffer: {33 9f 02 0b be 78 b3 98 43 d6 01 01 00 00 // 00 00 00 08 0d 0e c0 c1 b4 e9 b1 c4 36 9d 03 74 02 50 ce aa c5 94 // b1 b3 d7 41 dd 17 c1 8e 84 38 ef 2a 56 5e f1 e8 33 23 69 5c 58 d6 // 65 00 00 00 00 00} (length 0x40) lo_crypt_name: buffer: {a1 16 39 // 39 c7 87 a1 6c 1c a4 3f 85 39 f3 d3 28 97 37 f0 37 4c 72 a9 64 a0 // 19 3b 3e 87 72 fd 29 f3 52 39 d2 00 00 00 00 00 00 00 00 00 00 00 // 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00} (length 0x40) // lo_enc_key: buffer: {24 43 1a 39 77 a6 8e 17 4f 00 5e 95 ac 6a 00 // 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00} (length 0x20) // lo_init: array[int64] { // int64 = 0x0 (8 bytes) // int64 = 0x0 (8 bytes) // } // } // reserved: buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 // 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 // 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 // 00 00} (length 0x40) // } // } // ] NONFAILING(*(uint32_t*)0x200000000440 = r[0]); NONFAILING(*(uint32_t*)0x200000000444 = 0); NONFAILING(*(uint64_t*)0x200000000448 = 0); NONFAILING(*(uint64_t*)0x200000000450 = 0); NONFAILING(*(uint64_t*)0x200000000458 = 0); NONFAILING(*(uint64_t*)0x200000000460 = 8); NONFAILING(*(uint64_t*)0x200000000468 = 0); NONFAILING(*(uint32_t*)0x200000000470 = 0); NONFAILING(*(uint32_t*)0x200000000474 = 0); NONFAILING(*(uint32_t*)0x200000000478 = 0x13); NONFAILING(*(uint32_t*)0x20000000047c = 0x1c); NONFAILING( memcpy((void*)0x200000000480, "\x33\x9f\x02\x0b\xbe\x78\xb3\x98\x43\xd6\x01\x01\x00\x00\x00\x00" "\x00\x08\x0d\x0e\xc0\xc1\xb4\xe9\xb1\xc4\x36\x9d\x03\x74\x02\x50" "\xce\xaa\xc5\x94\xb1\xb3\xd7\x41\xdd\x17\xc1\x8e\x84\x38\xef\x2a" "\x56\x5e\xf1\xe8\x33\x23\x69\x5c\x58\xd6\x65\x00\x00\x00\x00\x00", 64)); NONFAILING( memcpy((void*)0x2000000004c0, "\xa1\x16\x39\x39\xc7\x87\xa1\x6c\x1c\xa4\x3f\x85\x39\xf3\xd3\x28" "\x97\x37\xf0\x37\x4c\x72\xa9\x64\xa0\x19\x3b\x3e\x87\x72\xfd\x29" "\xf3\x52\x39\xd2\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 64)); NONFAILING( memcpy((void*)0x200000000500, "\x24\x43\x1a\x39\x77\xa6\x8e\x17\x4f\x00\x5e\x95\xac\x6a\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 32)); NONFAILING(*(uint64_t*)0x200000000520 = 0); NONFAILING(*(uint64_t*)0x200000000528 = 0); NONFAILING(memset((void*)0x200000000530, 0, 64)); syscall(__NR_ioctl, /*fd=*/r[1], /*cmd=*/0x4c0a, /*arg=*/0x200000000440ul); // ioctl$FS_IOC_GETFSMAP arguments: [ // fd: fd (resource) // cmd: const = 0x4c09 (4 bytes) // arg: nil // ] syscall(__NR_ioctl, /*fd=*/r[1], /*cmd=*/0x4c09, /*arg=*/0ul); return 0; }