// https://syzkaller.appspot.com/bug?id=bda19bf6b14e7fddccf28ac6f0205c7df6d8c32e // 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 static void kill_and_wait(int pid, int* status) { kill(pid, SIGKILL); while (waitpid(-1, status, 0) != pid) { } } 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 void use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } static void reset_flags(const char* filename) { struct stat st; if (lstat(filename, &st)) exit(1); st.st_flags &= ~(SF_NOUNLINK | UF_NOUNLINK | SF_IMMUTABLE | UF_IMMUTABLE | SF_APPEND | UF_APPEND); if (lchflags(filename, st.st_flags)) exit(1); } static void __attribute__((noinline)) remove_dir(const char* dir) { DIR* dp = opendir(dir); if (dp == NULL) { if (errno == EACCES) { if (rmdir(dir)) exit(1); return; } exit(1); } struct dirent* ep = 0; while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } if (unlink(filename)) { if (errno == EPERM) { reset_flags(filename); reset_flags(dir); if (unlink(filename) == 0) continue; } exit(1); } } closedir(dp); while (rmdir(dir)) { if (errno == EPERM) { reset_flags(dir); if (rmdir(dir) == 0) break; } exit(1); } } static void execute_one(void); #define WAIT_FLAGS 0 static void loop(void) { int iter = 0; for (;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); 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; } remove_dir(cwdbuf); } } uint64_t r[2] = {0xffffffffffffffff, 0x0}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } syscall(SYS_socket, /*domain=*/2ul, /*type=*/0ul, /*proto=*/0x84); syscall(SYS_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0ul, /*flags=*/0ul, /*mode=*/0ul); syscall(SYS_open, /*file=*/0ul, /*flags=O_EMPTY_PATH*/ 0x2000000ul, /*mode=S_IXUSR*/ 0x40ul); syscall(SYS_socket, /*domain=*/2ul, /*type=SOCK_RAW*/ 3ul, /*proto=*/0); memcpy((void*)0x20000040, "/dev/filemon\000", 13); res = syscall(SYS_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000040ul, /*flags=*/0ul, /*mode=*/0ul); if (res != -1) r[0] = res; *(uint32_t*)0x20000000 = -1; syscall(SYS_ioctl, /*fd=*/r[0], /*cmd=*/0xc0045301ul, /*arg=*/0x20000000ul); res = syscall(SYS_setsid); if (res != -1) r[1] = res; *(uint32_t*)0x200002c0 = r[1]; syscall(SYS_ioctl, /*fd=*/r[0], /*cmd=*/0xc0045302ul, /*arg=*/0x200002c0ul); memcpy((void*)0x200004c0, "./file0\000", 8); syscall(SYS_open, /*file=*/0x200004c0ul, /*flags=O_CREAT*/ 0x200ul, /*mode=*/0ul); } int main(void) { syscall(SYS_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x1012ul, /*fd=*/-1, /*offset=*/0ul); const char* reason; (void)reason; use_temporary_dir(); loop(); return 0; }