// https://syzkaller.appspot.com/bug?id=15e04d241e7d50fe1ec19c23720c2b49be96827b // 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 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; } #define VHCI_HC_PORTS 8 #define VHCI_PORTS (VHCI_HC_PORTS * 2) static long syz_usbip_server_init(volatile long a0) { static int port_alloc[2]; int speed = (int)a0; bool usb3 = (speed == USB_SPEED_SUPER); int socket_pair[2]; if (socketpair(AF_UNIX, SOCK_STREAM, 0, socket_pair)) exit(1); int client_fd = socket_pair[0]; int server_fd = socket_pair[1]; int available_port_num = __atomic_fetch_add(&port_alloc[usb3], 1, __ATOMIC_RELAXED); if (available_port_num > VHCI_HC_PORTS) { return -1; } int port_num = procid * VHCI_PORTS + usb3 * VHCI_HC_PORTS + available_port_num; char buffer[100]; sprintf(buffer, "%d %d %s %d", port_num, client_fd, "0", speed); write_file("/sys/devices/platform/vhci_hcd.0/attach", buffer); return server_fd; } 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 { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } 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 USLEEP_FORKED_CHILD (3 * 50 * 1000) static long handle_clone_ret(long ret) { if (ret != 0) { __atomic_store_n(&clone_ongoing, 0, __ATOMIC_RELAXED); return ret; } usleep(USLEEP_FORKED_CHILD); syscall(__NR_exit, 0); while (1) { } } static long syz_clone(volatile long flags, volatile long stack, volatile long stack_len, volatile long ptid, volatile long ctid, volatile long tls) { long sp = (stack + stack_len) & ~15; __atomic_store_n(&clone_ongoing, 1, __ATOMIC_RELAXED); long ret = (long)syscall(__NR_clone, flags & ~CLONE_VM, sp, ptid, ctid, tls); return handle_clone_ret(ret); } 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[1] = {0x0}; void execute_one(void) { intptr_t res = 0; NONFAILING(syz_usbip_server_init(/*speed=*/5)); NONFAILING(syz_open_dev(/*dev=*/0, /*id=*/2, /*flags=*/0x141101)); NONFAILING(syz_open_dev(/*dev=*/0, /*id=*/2, /*flags=*/0x141101)); res = -1; NONFAILING(res = syz_clone(/*flags=*/0, /*stack=*/0, /*stack_len=*/0, /*parentid=*/0, /*childtid=*/0, /*tls=*/0)); if (res != -1) r[0] = res; syscall(__NR_ptrace, /*req=*/0x10ul, /*pid=*/r[0], 0, 0); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul); install_segv_handler(); loop(); return 0; }