// https://syzkaller.appspot.com/bug?id=054a54c07827f79a6a5b935f2de80919f4da9fda // 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 #ifndef __NR_fsconfig #define __NR_fsconfig 431 #endif #ifndef __NR_fsmount #define __NR_fsmount 432 #endif #ifndef __NR_fsopen #define __NR_fsopen 430 #endif static unsigned long long procid; 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 sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } 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 unsigned int queue_count = 2; 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_attr(nlmsg, IFLA_NUM_TX_QUEUES, &queue_count, sizeof(queue_count)); netlink_attr(nlmsg, IFLA_NUM_RX_QUEUES, &queue_count, sizeof(queue_count)); 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_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; } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); } #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; } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { int iter = 0; for (;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // syz_genetlink_get_family_id$ethtool arguments: [ // name: nil // fd: sock_nl_generic (resource) // ] // returns genl_ethtool_family_id NONFAILING(syz_genetlink_get_family_id(/*name=*/0, /*fd=*/-1)); // prctl$PR_SCHED_CORE arguments: [ // option: const = 0x3e (8 bytes) // cmd: intptr = 0x1 (8 bytes) // pid: pid (resource) // type: pid_type = 0x1 (8 bytes) // uaddr: nil // ] syscall(__NR_prctl, /*option=*/0x3eul, /*cmd=*/1ul, /*pid=*/0, /*type=PIDTYPE_TGID*/ 1ul, /*uaddr=*/0ul); // prlimit64 arguments: [ // pid: pid (resource) // res: rlimit_type = 0xe (8 bytes) // new: ptr[in, rlimit] { // rlimit { // soft: intptr = 0x8 (8 bytes) // hard: intptr = 0x100008b (8 bytes) // } // } // old: nil // ] NONFAILING(*(uint64_t*)0x200000000380 = 8); NONFAILING(*(uint64_t*)0x200000000388 = 0x100008b); syscall(__NR_prlimit64, /*pid=*/0, /*res=RLIMIT_RTPRIO*/ 0xeul, /*new=*/0x200000000380ul, /*old=*/0ul); // sched_setscheduler arguments: [ // pid: pid (resource) // policy: sched_policy = 0x1 (8 bytes) // prio: ptr[in, int32] { // int32 = 0x5 (4 bytes) // } // ] NONFAILING(*(uint32_t*)0x200000000200 = 5); syscall(__NR_sched_setscheduler, /*pid=*/0, /*policy=SCHED_FIFO*/ 1ul, /*prio=*/0x200000000200ul); // openat$sequencer arguments: [ // fd: const = 0xffffffffffffff9c (8 bytes) // file: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 73 65 71 75 65 6e 63 65 72 00} (length 0xf) // } // flags: open_flags = 0x80200 (4 bytes) // mode: const = 0x0 (2 bytes) // ] // returns fd_seq NONFAILING(memcpy((void*)0x200000000300, "/dev/sequencer\000", 15)); syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x200000000300ul, /*flags=O_TRUNC|O_CLOEXEC*/ 0x80200, /*mode=*/0); // fsopen arguments: [ // type: ptr[in, buffer] { // buffer: {72 61 6d 66 73 00} (length 0x6) // } // flags: fsopen_flags = 0x0 (8 bytes) // ] // returns fd_fscontext NONFAILING(memcpy((void*)0x2000000001c0, "ramfs\000", 6)); res = syscall(__NR_fsopen, /*type=*/0x2000000001c0ul, /*flags=*/0ul); if (res != -1) r[0] = res; // fsconfig$FSCONFIG_CMD_CREATE arguments: [ // fd: fd_fscontext (resource) // cmd: const = 0x6 (8 bytes) // key: const = 0x0 (8 bytes) // value: const = 0x0 (8 bytes) // aux: const = 0x0 (8 bytes) // ] syscall(__NR_fsconfig, /*fd=*/r[0], /*cmd=*/6ul, /*key=*/0ul, /*value=*/0ul, /*aux=*/0ul); // fsmount arguments: [ // fs_fd: fd_fscontext (resource) // flags: fsmount_flags = 0x0 (8 bytes) // attr_flags: fsmount_attr_flags = 0x0 (8 bytes) // ] // returns fd res = syscall(__NR_fsmount, /*fs_fd=*/r[0], /*flags=*/0ul, /*attr_flags=*/0ul); if (res != -1) r[1] = res; // fchown arguments: [ // fd: fd (resource) // uid: uid (resource) // gid: gid (resource) // ] syscall(__NR_fchown, /*fd=*/(intptr_t)-1, /*uid=*/0, /*gid=*/0); // fchdir arguments: [ // fd: fd (resource) // ] syscall(__NR_fchdir, /*fd=*/r[1]); // open arguments: [ // file: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: open_flags = 0x143142 (8 bytes) // mode: open_mode = 0x80 (8 bytes) // ] // returns fd NONFAILING(memcpy((void*)0x200000000040, "./bus\000", 6)); syscall(__NR_open, /*file=*/0x200000000040ul, /*flags=O_SYNC|O_NOCTTY|O_NOATIME|O_CREAT|FASYNC|0x2*/ 0x143142ul, /*mode=S_IWUSR*/ 0x80ul); // openat arguments: [ // fd: fd_dir (resource) // file: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: open_flags = 0x0 (4 bytes) // mode: open_mode = 0x10 (2 bytes) // ] // returns fd NONFAILING(memcpy((void*)0x200000000080, "./bus\000", 6)); res = syscall(__NR_openat, /*fd=*/r[1], /*file=*/0x200000000080ul, /*flags=*/0, /*mode=S_IWGRP*/ 0x10); if (res != -1) r[2] = res; // openat arguments: [ // fd: fd_dir (resource) // file: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: open_flags = 0x1c1002 (4 bytes) // mode: open_mode = 0x50 (2 bytes) // ] // returns fd NONFAILING(memcpy((void*)0x200000000000, "./bus\000", 6)); res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x200000000000ul, /*flags=O_SYNC|O_NOATIME|O_CLOEXEC|O_RDWR*/ 0x1c1002, /*mode=S_IWGRP|S_IXUSR*/ 0x50); if (res != -1) r[3] = res; // write arguments: [ // fd: fd (resource) // buf: ptr[in, buffer] { // buffer: {74} (length 0x1) // } // count: len = 0x1 (8 bytes) // ] NONFAILING(memset((void*)0x200000004200, 116, 1)); syscall(__NR_write, /*fd=*/r[3], /*buf=*/0x200000004200ul, /*count=*/1ul); // sendfile arguments: [ // fdout: fd (resource) // fdin: fd (resource) // off: nil // count: intptr = 0x7fffffff (8 bytes) // ] syscall(__NR_sendfile, /*fdout=*/r[3], /*fdin=*/r[2], /*off=*/0ul, /*count=*/0x7ffffffful); // mkdir arguments: [ // path: nil // mode: open_mode = 0x0 (8 bytes) // ] syscall(__NR_mkdir, /*path=*/0ul, /*mode=*/0ul); // mkdir arguments: [ // path: nil // mode: open_mode = 0x0 (8 bytes) // ] syscall(__NR_mkdir, /*path=*/0ul, /*mode=*/0ul); // mknodat$loop arguments: [ // dirfd: fd_dir (resource) // file: nil // mode: mknod_mode = 0x0 (8 bytes) // dev: proc = 0x0 (4 bytes) // ] syscall(__NR_mknodat, /*dirfd=*/(intptr_t)-1, /*file=*/0ul, /*mode=*/0ul, /*dev=*/0x700 + procid * 2); // linkat arguments: [ // oldfd: fd_dir (resource) // old: nil // newfd: fd_dir (resource) // new: nil // flags: linkat_flags = 0x0 (8 bytes) // ] syscall(__NR_linkat, /*oldfd=*/(intptr_t)-1, /*old=*/0ul, /*newfd=*/(intptr_t)-1, /*new=*/0ul, /*flags=*/0ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000, /*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=*/0x1000, /*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())) { fprintf(stderr, "reproducer setup failed: 802154 injection: %s\n", reason); exit(1); } install_segv_handler(); for (procid = 0; procid < 5; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }