// 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 #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 #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 exitf(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(kRetryStatus); } 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 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 void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_IO); } 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) { close(fd); return false; } close(fd); return true; } static int real_uid; static int real_gid; __attribute__((aligned(64 << 10))) static char sandbox_stack[1 << 20]; static int namespace_sandbox_proc(void* arg) { sandbox_common(); write_file("/proc/self/setgroups", "deny"); if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid)) fail("write of /proc/self/uid_map failed"); if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) fail("write of /proc/self/gid_map failed"); if (mkdir("./syz-tmp", 0777)) fail("mkdir(syz-tmp) failed"); if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) fail("mount(tmpfs) failed"); if (mkdir("./syz-tmp/newroot", 0777)) fail("mkdir failed"); if (mkdir("./syz-tmp/newroot/dev", 0700)) fail("mkdir failed"); if (mount("/dev", "./syz-tmp/newroot/dev", NULL, MS_BIND | MS_REC | MS_PRIVATE, NULL)) fail("mount(dev) failed"); if (mkdir("./syz-tmp/newroot/proc", 0700)) fail("mkdir failed"); if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL)) fail("mount(proc) failed"); if (mkdir("./syz-tmp/pivot", 0777)) fail("mkdir failed"); if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { if (chdir("./syz-tmp")) fail("chdir failed"); } else { if (chdir("/")) fail("chdir failed"); if (umount2("./pivot", MNT_DETACH)) fail("umount failed"); } if (chroot("./newroot")) fail("chroot failed"); if (chdir("/")) fail("chdir failed"); struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) fail("capget failed"); cap_data[0].effective &= ~(1 << CAP_SYS_PTRACE); cap_data[0].permitted &= ~(1 << CAP_SYS_PTRACE); cap_data[0].inheritable &= ~(1 << CAP_SYS_PTRACE); if (syscall(SYS_capset, &cap_hdr, &cap_data)) fail("capset failed"); loop(); doexit(1); } static int do_sandbox_namespace(int executor_pid, bool enable_tun) { real_uid = getuid(); real_gid = getgid(); mprotect(sandbox_stack, 4096, PROT_NONE); return clone( namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64], CLONE_NEWUSER | CLONE_NEWPID | CLONE_NEWUTS | CLONE_NEWNET, NULL); } static void remove_dir(const char* dir) { DIR* dp; struct dirent* ep; int iter = 0; retry: dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exitf("opendir(%s) failed due to NOFILE, exiting"); } exitf("opendir(%s) failed", dir); } 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)) exitf("lstat(%s) failed", filename); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { if (unlink(filename) == 0) break; if (errno == EROFS) { break; } if (errno != EBUSY || i > 100) exitf("unlink(%s) failed", filename); if (umount2(filename, MNT_DETACH)) exitf("umount(%s) failed", filename); } } closedir(dp); int i; for (i = 0;; i++) { if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EROFS) { break; } if (errno == EBUSY) { if (umount2(dir, MNT_DETACH)) exitf("umount(%s) failed", dir); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exitf("rmdir(%s) failed", dir); } } static void test(); void loop() { int iter; for (iter = 0;; iter++) { char cwdbuf[256]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) fail("failed to mkdir"); int pid = fork(); if (pid < 0) fail("clone failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); if (chdir(cwdbuf)) fail("failed to chdir"); test(); 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 > 5 * 1000) { kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } remove_dir(cwdbuf); } } long r[75]; void test() { memset(r, -1, sizeof(r)); r[0] = syscall(__NR_mmap, 0x20000000ul, 0xfff000ul, 0x3ul, 0x32ul, 0xfffffffffffffffful, 0x0ul); memcpy((void*)0x20632000, "\x2e\x2f\x66\x69\x6c\x65\x30\x00", 8); r[2] = syscall(__NR_mkdir, 0x20632000ul, 0x16ul); memcpy((void*)0x2000a000, "\x2e\x2f\x66\x69\x6c\x65\x30\x00", 8); memcpy((void*)0x20014ff8, "\x2e\x2f\x66\x69\x6c\x65\x30\x00", 8); memcpy((void*)0x20014000, "\x70\x72\x6f\x63\x00", 5); r[6] = syscall(__NR_mount, 0x2000a000ul, 0x20014ff8ul, 0x20014000ul, 0x0ul, 0x20fc9000ul); r[7] = syscall(__NR_socket, 0x10ul, 0x3ul, 0x6ul); *(uint16_t*)0x204ff000 = (uint16_t)0x10; *(uint16_t*)0x204ff002 = (uint16_t)0x0; *(uint32_t*)0x204ff004 = (uint32_t)0xfffffffffffffffe; *(uint32_t*)0x204ff008 = (uint32_t)0x5; r[12] = syscall(__NR_bind, r[7], 0x204ff000ul, 0xcul); r[13] = syscall(__NR_socket, 0x2ul, 0x3ul, 0x2ful); *(uint32_t*)0x20000000 = (uint32_t)0x100007f; *(uint8_t*)0x20000010 = (uint8_t)0xac; *(uint8_t*)0x20000011 = (uint8_t)0x14; *(uint8_t*)0x20000012 = (uint8_t)0x0; *(uint8_t*)0x20000013 = (uint8_t)0xbb; *(uint16_t*)0x20000020 = (uint16_t)0x204e; *(uint16_t*)0x20000022 = (uint16_t)0x0; *(uint16_t*)0x20000024 = (uint16_t)0x204e; *(uint16_t*)0x20000026 = (uint16_t)0x0; *(uint16_t*)0x20000028 = (uint16_t)0x2; *(uint8_t*)0x2000002a = (uint8_t)0x0; *(uint8_t*)0x2000002b = (uint8_t)0x0; *(uint8_t*)0x2000002c = (uint8_t)0x0; *(uint32_t*)0x20000030 = (uint32_t)0x0; *(uint32_t*)0x20000034 = (uint32_t)0x0; *(uint64_t*)0x20000038 = (uint64_t)0x0; *(uint64_t*)0x20000040 = (uint64_t)0x0; *(uint64_t*)0x20000048 = (uint64_t)0x0; *(uint64_t*)0x20000050 = (uint64_t)0x0; *(uint64_t*)0x20000058 = (uint64_t)0x0; *(uint64_t*)0x20000060 = (uint64_t)0x0; *(uint64_t*)0x20000068 = (uint64_t)0x0; *(uint64_t*)0x20000070 = (uint64_t)0x0; *(uint64_t*)0x20000078 = (uint64_t)0x0; *(uint64_t*)0x20000080 = (uint64_t)0x0; *(uint64_t*)0x20000088 = (uint64_t)0x0; *(uint64_t*)0x20000090 = (uint64_t)0x0; *(uint32_t*)0x20000098 = (uint32_t)0x0; *(uint32_t*)0x2000009c = (uint32_t)0x0; *(uint8_t*)0x200000a0 = (uint8_t)0x1; *(uint8_t*)0x200000a1 = (uint8_t)0x0; *(uint8_t*)0x200000a2 = (uint8_t)0x0; *(uint8_t*)0x200000a3 = (uint8_t)0x0; *(uint32_t*)0x200000a8 = (uint32_t)0x2000000; *(uint32_t*)0x200000b8 = (uint32_t)0x0; *(uint8_t*)0x200000bc = (uint8_t)0x0; *(uint16_t*)0x200000c0 = (uint16_t)0x0; *(uint8_t*)0x200000c4 = (uint8_t)0xac; *(uint8_t*)0x200000c5 = (uint8_t)0x14; *(uint8_t*)0x200000c6 = (uint8_t)0x0; *(uint8_t*)0x200000c7 = (uint8_t)0xaa; *(uint32_t*)0x200000d4 = (uint32_t)0x0; *(uint8_t*)0x200000d8 = (uint8_t)0x0; *(uint8_t*)0x200000d9 = (uint8_t)0x0; *(uint8_t*)0x200000da = (uint8_t)0xfffffffffffffffd; *(uint32_t*)0x200000dc = (uint32_t)0x0; *(uint32_t*)0x200000e0 = (uint32_t)0x0; *(uint32_t*)0x200000e4 = (uint32_t)0x0; r[62] = syscall(__NR_setsockopt, r[13], 0x0ul, 0x11ul, 0x20000000ul, 0xe8ul); *(uint16_t*)0x20c24000 = (uint16_t)0x2; *(uint16_t*)0x20c24002 = (uint16_t)0x224e; *(uint32_t*)0x20c24004 = (uint32_t)0x0; *(uint8_t*)0x20c24008 = (uint8_t)0x0; *(uint8_t*)0x20c24009 = (uint8_t)0x0; *(uint8_t*)0x20c2400a = (uint8_t)0x0; *(uint8_t*)0x20c2400b = (uint8_t)0x0; *(uint8_t*)0x20c2400c = (uint8_t)0x0; *(uint8_t*)0x20c2400d = (uint8_t)0x0; *(uint8_t*)0x20c2400e = (uint8_t)0x0; *(uint8_t*)0x20c2400f = (uint8_t)0x0; r[74] = syscall(__NR_sendto, r[13], 0x205cdffeul, 0x0ul, 0x8ul, 0x20c24000ul, 0x10ul); } int main() { int i; for (i = 0; i < 8; i++) { if (fork() == 0) { use_temporary_dir(); int pid = do_sandbox_namespace(i, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; } } sleep(1000000); return 0; }