// https://syzkaller.appspot.com/bug?id=3b6a05622c30f88ed585de2085fffc3440d4104a // 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 #ifndef __NR_bpf #define __NR_bpf 321 #endif 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; \ }) static void use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } #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)))) 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[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 void setup_sysctl() { char mypid[32]; snprintf(mypid, sizeof(mypid), "%d", getpid()); struct { const char* name; const char* data; } files[] = { {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"}, {"/proc/sys/kernel/hung_task_check_interval_secs", "20"}, {"/proc/sys/net/core/bpf_jit_kallsyms", "1"}, {"/proc/sys/net/core/bpf_jit_harden", "0"}, {"/proc/sys/kernel/kptr_restrict", "0"}, {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"}, {"/proc/sys/fs/mount-max", "100"}, {"/proc/sys/vm/oom_dump_tasks", "0"}, {"/proc/sys/debug/exception-trace", "0"}, {"/proc/sys/kernel/printk", "7 4 1 3"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, {"/proc/sys/kernel/ctrl-alt-del", "0"}, {"/proc/sys/kernel/cad_pid", mypid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) printf("write to %s failed: %s\n", files[i].name, strerror(errno)); } } #define NL802154_CMD_SET_SHORT_ADDR 11 #define NL802154_ATTR_IFINDEX 3 #define NL802154_ATTR_SHORT_ADDR 10 static void setup_802154() { int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock_route == -1) exit(1); int sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock_generic < 0) exit(1); int nl802154_family_id = netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true); 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)); int err = netlink_send(&nlmsg, sock_generic); if (err < 0) { } 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)); int err = netlink_send(&nlmsg, sock_route); if (err < 0) { } } } close(sock_route); close(sock_generic); } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); setup_sysctl(); setup_802154(); install_segv_handler(); use_temporary_dir(); intptr_t res = 0; NONFAILING(*(uint32_t*)0x200009c0 = 0x12); NONFAILING(*(uint32_t*)0x200009c4 = 4); NONFAILING(*(uint32_t*)0x200009c8 = 8); NONFAILING(*(uint32_t*)0x200009cc = 8); NONFAILING(*(uint32_t*)0x200009d0 = 0); NONFAILING(*(uint32_t*)0x200009d4 = -1); NONFAILING(*(uint32_t*)0x200009d8 = 0); NONFAILING(memset((void*)0x200009dc, 0, 16)); NONFAILING(*(uint32_t*)0x200009ec = 0); NONFAILING(*(uint32_t*)0x200009f0 = -1); NONFAILING(*(uint32_t*)0x200009f4 = 0); NONFAILING(*(uint32_t*)0x200009f8 = 0); NONFAILING(*(uint32_t*)0x200009fc = 0); NONFAILING(*(uint64_t*)0x20000a00 = 0); res = syscall(__NR_bpf, /*cmd=*/0ul, /*arg=*/0x200009c0ul, /*size=*/0x48ul); if (res != -1) r[0] = res; NONFAILING(*(uint32_t*)0x200000c0 = 0); NONFAILING(*(uint32_t*)0x200000c4 = 0xc); NONFAILING(*(uint64_t*)0x200000c8 = 0x20000440); NONFAILING(*(uint8_t*)0x20000440 = 0x18); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000441, 0, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000441, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000442 = 0); NONFAILING(*(uint32_t*)0x20000444 = 0); NONFAILING(*(uint8_t*)0x20000448 = 0); NONFAILING(*(uint8_t*)0x20000449 = 0); NONFAILING(*(uint16_t*)0x2000044a = 0); NONFAILING(*(uint32_t*)0x2000044c = 0); NONFAILING(*(uint8_t*)0x20000450 = 0x18); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000451, 1, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000451, 1, 4, 4)); NONFAILING(*(uint16_t*)0x20000452 = 0); NONFAILING(*(uint32_t*)0x20000454 = r[0]); NONFAILING(*(uint8_t*)0x20000458 = 0); NONFAILING(*(uint8_t*)0x20000459 = 0); NONFAILING(*(uint16_t*)0x2000045a = 0); NONFAILING(*(uint32_t*)0x2000045c = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000460, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000460, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000460, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000461, 8, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000461, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000462 = 0); NONFAILING(*(uint32_t*)0x20000464 = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000468, 3, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000468, 3, 3, 2)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000468, 3, 5, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000469, 0xa, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000469, 8, 4, 4)); NONFAILING(*(uint16_t*)0x2000046a = 0xfff8); NONFAILING(*(uint32_t*)0x2000046c = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000470, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000470, 1, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000470, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000471, 2, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000471, 0xa, 4, 4)); NONFAILING(*(uint16_t*)0x20000472 = 0); NONFAILING(*(uint32_t*)0x20000474 = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000478, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000478, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000478, 0, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000479, 2, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000479, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000047a = 0); NONFAILING(*(uint32_t*)0x2000047c = 0xfffffff8); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000480, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000480, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000480, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000481, 3, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000481, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000482 = 0); NONFAILING(*(uint32_t*)0x20000484 = 8); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000488, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000488, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000488, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000489, 4, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000489, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000048a = 0); NONFAILING(*(uint32_t*)0x2000048c = 0); NONFAILING(*(uint8_t*)0x20000490 = 0x85); NONFAILING(*(uint8_t*)0x20000491 = 0); NONFAILING(*(uint16_t*)0x20000492 = 0); NONFAILING(*(uint32_t*)0x20000494 = 3); NONFAILING(*(uint8_t*)0x20000498 = 0x95); NONFAILING(*(uint8_t*)0x20000499 = 0); NONFAILING(*(uint16_t*)0x2000049a = 0); NONFAILING(*(uint32_t*)0x2000049c = 0); NONFAILING(*(uint64_t*)0x200000d0 = 0); NONFAILING(*(uint32_t*)0x200000d8 = 0); NONFAILING(*(uint32_t*)0x200000dc = 0); NONFAILING(*(uint64_t*)0x200000e0 = 0); NONFAILING(*(uint32_t*)0x200000e8 = 0); NONFAILING(*(uint32_t*)0x200000ec = 0); NONFAILING(memset((void*)0x200000f0, 0, 16)); NONFAILING(*(uint32_t*)0x20000100 = 0); NONFAILING(*(uint32_t*)0x20000104 = 0); NONFAILING(*(uint32_t*)0x20000108 = -1); NONFAILING(*(uint32_t*)0x2000010c = 0); NONFAILING(*(uint64_t*)0x20000110 = 0); NONFAILING(*(uint32_t*)0x20000118 = 0); NONFAILING(*(uint32_t*)0x2000011c = 0); NONFAILING(*(uint64_t*)0x20000120 = 0); NONFAILING(*(uint32_t*)0x20000128 = 0); NONFAILING(*(uint32_t*)0x2000012c = 0); NONFAILING(*(uint32_t*)0x20000130 = 0); NONFAILING(*(uint32_t*)0x20000134 = 0); NONFAILING(*(uint64_t*)0x20000138 = 0); NONFAILING(*(uint64_t*)0x20000140 = 0); NONFAILING(*(uint32_t*)0x20000148 = 0); NONFAILING(*(uint32_t*)0x2000014c = 0); syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200000c0ul, /*size=*/0x90ul); NONFAILING(*(uint32_t*)0x200007c0 = 0x11); NONFAILING(*(uint32_t*)0x200007c4 = 0xc); NONFAILING(*(uint64_t*)0x200007c8 = 0x20000440); NONFAILING(*(uint64_t*)0x200007d0 = 0x20000880); NONFAILING(memcpy((void*)0x20000880, "GPL\000", 4)); NONFAILING(*(uint32_t*)0x200007d8 = 0); NONFAILING(*(uint32_t*)0x200007dc = 0); NONFAILING(*(uint64_t*)0x200007e0 = 0); NONFAILING(*(uint32_t*)0x200007e8 = 0); NONFAILING(*(uint32_t*)0x200007ec = 0); NONFAILING(memset((void*)0x200007f0, 0, 16)); NONFAILING(*(uint32_t*)0x20000800 = 0); NONFAILING(*(uint32_t*)0x20000804 = 0); NONFAILING(*(uint32_t*)0x20000808 = -1); NONFAILING(*(uint32_t*)0x2000080c = 0); NONFAILING(*(uint64_t*)0x20000810 = 0); NONFAILING(*(uint32_t*)0x20000818 = 0); NONFAILING(*(uint32_t*)0x2000081c = 0); NONFAILING(*(uint64_t*)0x20000820 = 0); NONFAILING(*(uint32_t*)0x20000828 = 0); NONFAILING(*(uint32_t*)0x2000082c = 0); NONFAILING(*(uint32_t*)0x20000830 = 0); NONFAILING(*(uint32_t*)0x20000834 = 0); NONFAILING(*(uint64_t*)0x20000838 = 0); NONFAILING(*(uint64_t*)0x20000840 = 0); NONFAILING(*(uint32_t*)0x20000848 = 0); NONFAILING(*(uint32_t*)0x2000084c = 0); res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200007c0ul, /*size=*/0x90ul); if (res != -1) r[1] = res; NONFAILING(*(uint64_t*)0x20000040 = 0x20000000); NONFAILING(memcpy((void*)0x20000000, "timer_start\000", 12)); NONFAILING(*(uint32_t*)0x20000048 = r[1]); syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x20000040ul, /*size=*/0x10ul); return 0; }