// https://syzkaller.appspot.com/bug?id=5735d842f7ea3ed9220aca64952ac4aba7ba741c // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #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 #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 void use_temporary_dir() { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } 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; void loop() { while (1) { execute_one(); } } uint64_t r[1] = {0xffffffffffffffff}; unsigned long long procid; void execute_one() { long res = 0; memcpy((void*)0x20000200, "/dev/net/tun", 13); syz_open_dev(0x20000200, 0, 0); memcpy((void*)0x20000040, "/dev/net/tun", 13); res = syz_open_dev(0x20000040, 0, 0); if (res != -1) r[0] = res; memcpy((void*)0x200000c0, "\x69\x00\x02\x00\x00\x0f\x00\x2d\xc8\x30\xee\x00\x00\x00\x00\x5d", 16); *(uint16_t*)0x200000d0 = 0x103; syscall(__NR_ioctl, r[0], 0x400454ca, 0x200000c0); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); char* cwd = get_current_dir_name(); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { if (chdir(cwd)) fail("failed to chdir"); use_temporary_dir(); loop(); } } } sleep(1000000); return 0; }