// https://syzkaller.appspot.com/bug?id=3153e27944712d6149bbd81691fdcdc7cbdc0e60 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void fail(const char* msg, ...) { int e = errno; va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); } static uint64_t current_time_ms() { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) fail("clock_gettime failed"); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t 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 execute_one(); extern unsigned long long procid; static void loop() { int iter; for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) fail("clone failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); execute_one(); doexit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { int res = waitpid(-1, &status, __WALL | WNOHANG); if (res == pid) { break; } usleep(1000); if (current_time_ms() - start < 3 * 1000) continue; kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } } #ifndef __NR_memfd_create #define __NR_memfd_create 319 #endif uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_one() { long res = 0; memcpy((void*)0x20000100, "/dev/loop#", 11); res = syz_open_dev(0x20000100, 0, 0); if (res != -1) r[0] = res; memcpy((void*)0x20000140, "\x00\x00\x00\x00\x8c\x00\x40\x00\x01\x00\x00\x00\x00\x00\x00", 15); res = syscall(__NR_memfd_create, 0x20000140, 0); if (res != -1) r[1] = res; *(uint64_t*)0x200000c0 = 0x20000180; memcpy((void*)0x20000180, "\xa8", 1); *(uint64_t*)0x200000c8 = 1; syscall(__NR_pwritev, r[1], 0x200000c0, 1, 0x1081003); syscall(__NR_ioctl, r[0], 0x4c00, r[1]); syscall(__NR_ioctl, r[0], 0x4c06, r[0]); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (;;) { loop(); } }