// https://syzkaller.appspot.com/bug?id=15631d6cf59940a001754b2b197c208abc798221 // 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 #ifndef __NR_bpf #define __NR_bpf 321 #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; } #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 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_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 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"); } 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)); } } 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 (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one(void) { intptr_t res = 0; NONFAILING(*(uint32_t*)0x20000340 = 2); NONFAILING(*(uint32_t*)0x20000344 = 4); NONFAILING(*(uint32_t*)0x20000348 = 8); NONFAILING(*(uint32_t*)0x2000034c = 1); NONFAILING(*(uint32_t*)0x20000350 = 0x80); NONFAILING(*(uint32_t*)0x20000354 = -1); NONFAILING(*(uint32_t*)0x20000358 = 0); NONFAILING(memset((void*)0x2000035c, 0, 16)); NONFAILING(*(uint32_t*)0x2000036c = 0); NONFAILING(*(uint32_t*)0x20000370 = -1); NONFAILING(*(uint32_t*)0x20000374 = 0); NONFAILING(*(uint32_t*)0x20000378 = 0); NONFAILING(*(uint32_t*)0x2000037c = 0); NONFAILING(*(uint64_t*)0x20000380 = 0); res = syscall(__NR_bpf, /*cmd=*/0ul, /*arg=*/0x20000340ul, /*size=*/0x48ul); if (res != -1) r[0] = res; NONFAILING(*(uint32_t*)0x20000480 = r[0]); syscall(__NR_bpf, /*cmd=*/0x16ul, /*arg=*/0x20000480ul, /*size=*/4ul); NONFAILING(*(uint32_t*)0x200004c0 = 0x11); NONFAILING(*(uint32_t*)0x200004c4 = 0x18); NONFAILING(*(uint64_t*)0x200004c8 = 0x200001c0); NONFAILING( memcpy((void*)0x200001c0, "\x18\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\xb7\x08\x00\x00\x00\x00\x00\x00\x7b\x8a\xf8\xff\x00\x00\x00\x00" "\xb7\x08\x00\x00\x00\x00\x00\x00\x7b\x8a\xf0\xff\x00\x00\x00\x00" "\xbf\xa1\x00\x00\x00\x00\x00\x00\x07\x01\x00\x00\xf8\xff\xff\xff" "\xbf\xa4\x00\x00\x00\x00\x00\x00\x07\x04\x00\x00\xf0\xff\xff\xff" "\xb7\x02\x00\x00\x00\x00\x00\x00\x18\x23\x00\x00", 92)); NONFAILING(*(uint32_t*)0x2000021c = r[0]); NONFAILING(memcpy( (void*)0x20000220, "\x00\x00\x00\x00\x00\x00\x00\x00\xb7\x05\x00\x00\x00\x00\x00\x00\x85\x00" "\x00\x00\xa5\x00\x00\x00\x18\x01\x00\x00\x20\x20\x64\x05\x00\x00\x00\x00" "\x00\x20\x20\x20\x7b\x1a\xf8\xff\x00\x00\x00\x00\xbf\xa1\x00\x00\x00\x00" "\x00\x00\x07\x01\x00\x00\xf8\xff\xff\xff\xb7\x02\x00\x00\x08\x00\x00\x00" "\xb7\x03\x00\x00\x00\x00\x00\x00\xa5\x00\x00\x00\x08\x00\x00\x00\x95", 89)); NONFAILING(*(uint64_t*)0x200004d0 = 0x20000600); NONFAILING(memcpy((void*)0x20000600, "GPL\000", 4)); NONFAILING(*(uint32_t*)0x200004d8 = 0); NONFAILING(*(uint32_t*)0x200004dc = 0); NONFAILING(*(uint64_t*)0x200004e0 = 0); NONFAILING(*(uint32_t*)0x200004e8 = 0); NONFAILING(*(uint32_t*)0x200004ec = 0); NONFAILING(memset((void*)0x200004f0, 0, 16)); NONFAILING(*(uint32_t*)0x20000500 = 0); NONFAILING(*(uint32_t*)0x20000504 = 0); NONFAILING(*(uint32_t*)0x20000508 = 0); NONFAILING(*(uint32_t*)0x2000050c = 0); NONFAILING(*(uint64_t*)0x20000510 = 0); NONFAILING(*(uint32_t*)0x20000518 = 0); NONFAILING(*(uint32_t*)0x2000051c = 0); NONFAILING(*(uint64_t*)0x20000520 = 0); NONFAILING(*(uint32_t*)0x20000528 = 0); NONFAILING(*(uint32_t*)0x2000052c = 0); NONFAILING(*(uint32_t*)0x20000530 = 0); NONFAILING(*(uint32_t*)0x20000534 = 0); NONFAILING(*(uint64_t*)0x20000538 = 0); NONFAILING(*(uint64_t*)0x20000540 = 0); NONFAILING(*(uint32_t*)0x20000548 = 0); NONFAILING(*(uint32_t*)0x2000054c = 0); res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200004c0ul, /*size=*/0x90ul); if (res != -1) r[1] = res; NONFAILING(*(uint64_t*)0x200001c0 = 0x20000000); NONFAILING(memcpy((void*)0x20000000, "kfree\000", 6)); NONFAILING(*(uint32_t*)0x200001c8 = r[1]); syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x200001c0ul, /*size=*/0x10ul); syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0ul, /*size=*/0ul); syscall(__NR_bpf, /*cmd=*/2ul, /*arg=*/0ul, /*size=*/0ul); NONFAILING(syz_genetlink_get_family_id(/*name=*/0, /*fd=*/-1)); syscall(__NR_sendmsg, /*fd=*/-1, /*msg=*/0ul, /*f=*/0ul); NONFAILING(*(uint32_t*)0x200000c0 = 0x11); NONFAILING(*(uint32_t*)0x200000c4 = 0xb); NONFAILING(*(uint64_t*)0x200000c8 = 0x20000240); NONFAILING(*(uint8_t*)0x20000240 = 0x18); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000241, 0, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000241, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000242 = 0); NONFAILING(*(uint32_t*)0x20000244 = 0); NONFAILING(*(uint8_t*)0x20000248 = 0); NONFAILING(*(uint8_t*)0x20000249 = 0); NONFAILING(*(uint16_t*)0x2000024a = 0); NONFAILING(*(uint32_t*)0x2000024c = 0); NONFAILING(*(uint8_t*)0x20000250 = 0x18); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000251, 1, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000251, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000252 = 0); NONFAILING(*(uint32_t*)0x20000254 = 0x25702020); NONFAILING(*(uint8_t*)0x20000258 = 0); NONFAILING(*(uint8_t*)0x20000259 = 0); NONFAILING(*(uint16_t*)0x2000025a = 0); NONFAILING(*(uint32_t*)0x2000025c = 0x20202000); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000260, 3, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000260, 3, 3, 2)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000260, 3, 5, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000261, 0xa, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000261, 1, 4, 4)); NONFAILING(*(uint16_t*)0x20000262 = 0xfff8); NONFAILING(*(uint32_t*)0x20000264 = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000268, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000268, 1, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000268, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000269, 1, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000269, 0xa, 4, 4)); NONFAILING(*(uint16_t*)0x2000026a = 0); NONFAILING(*(uint32_t*)0x2000026c = 0); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000270, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000270, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000270, 0, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000271, 1, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000271, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000272 = 0); NONFAILING(*(uint32_t*)0x20000274 = 0xfffffff8); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000278, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000278, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000278, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000279, 2, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000279, 0, 4, 4)); NONFAILING(*(uint16_t*)0x2000027a = 0); NONFAILING(*(uint32_t*)0x2000027c = 8); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000280, 7, 0, 3)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000280, 0, 3, 1)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000280, 0xb, 4, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000281, 3, 0, 4)); NONFAILING(STORE_BY_BITMASK(uint8_t, , 0x20000281, 0, 4, 4)); NONFAILING(*(uint16_t*)0x20000282 = 0); NONFAILING(*(uint32_t*)0x20000284 = 0); NONFAILING(*(uint8_t*)0x20000288 = 0x85); NONFAILING(*(uint8_t*)0x20000289 = 0); NONFAILING(*(uint16_t*)0x2000028a = 0); NONFAILING(*(uint32_t*)0x2000028c = 6); NONFAILING(*(uint8_t*)0x20000290 = 0x95); NONFAILING(*(uint8_t*)0x20000291 = 0); NONFAILING(*(uint16_t*)0x20000292 = 0); NONFAILING(*(uint32_t*)0x20000294 = 0); NONFAILING(*(uint64_t*)0x200000d0 = 0x20000200); NONFAILING(memcpy((void*)0x20000200, "GPL\000", 4)); 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); res = syscall(__NR_bpf, /*cmd=*/5ul, /*arg=*/0x200000c0ul, /*size=*/0x90ul); if (res != -1) r[2] = res; NONFAILING(*(uint64_t*)0x200007c0 = 0x20000080); NONFAILING(memcpy((void*)0x20000080, "sys_enter\000", 10)); NONFAILING(*(uint32_t*)0x200007c8 = r[2]); syscall(__NR_bpf, /*cmd=*/0x11ul, /*arg=*/0x200007c0ul, /*size=*/0x10ul); } 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(); install_segv_handler(); for (procid = 0; procid < 5; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }