| // KMSAN: kernel-infoleak in kvm_arch_vcpu_ioctl |
| // https://syzkaller.appspot.com/bug?id=07e1807f4e0e8db03fbb6a38671c012f8887901f |
| // status:fixed |
| // autogenerated by syzkaller (https://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| |
| #include <dirent.h> |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <pthread.h> |
| #include <sched.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/ioctl.h> |
| #include <sys/mman.h> |
| #include <sys/mount.h> |
| #include <sys/prctl.h> |
| #include <sys/resource.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <time.h> |
| #include <unistd.h> |
| |
| #include <linux/capability.h> |
| #include <linux/futex.h> |
| |
| 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 thread_start(void* (*fn)(void*), void* arg) |
| { |
| pthread_t th; |
| pthread_attr_t attr; |
| pthread_attr_init(&attr); |
| pthread_attr_setstacksize(&attr, 128 << 10); |
| if (pthread_create(&th, &attr, fn, arg)) |
| exit(1); |
| pthread_attr_destroy(&attr); |
| } |
| |
| typedef struct { |
| int state; |
| } event_t; |
| |
| static void event_init(event_t* ev) |
| { |
| ev->state = 0; |
| } |
| |
| static void event_reset(event_t* ev) |
| { |
| ev->state = 0; |
| } |
| |
| static void event_set(event_t* ev) |
| { |
| if (ev->state) |
| exit(1); |
| __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE); |
| syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG); |
| } |
| |
| static void event_wait(event_t* ev) |
| { |
| while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) |
| syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0); |
| } |
| |
| static int event_isset(event_t* ev) |
| { |
| return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE); |
| } |
| |
| static int event_timedwait(event_t* ev, uint64_t timeout) |
| { |
| uint64_t start = current_time_ms(); |
| uint64_t now = start; |
| for (;;) { |
| uint64_t remain = timeout - (now - start); |
| struct timespec ts; |
| ts.tv_sec = remain / 1000; |
| ts.tv_nsec = (remain % 1000) * 1000 * 1000; |
| syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts); |
| if (__atomic_load_n(&ev->state, __ATOMIC_RELAXED)) |
| return 1; |
| now = current_time_ms(); |
| if (now - start > timeout) |
| return 0; |
| } |
| } |
| |
| 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; |
| } |
| |
| static void setup_common() |
| { |
| if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { |
| } |
| } |
| |
| 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 = 200 << 20; |
| setrlimit(RLIMIT_AS, &rlim); |
| rlim.rlim_cur = rlim.rlim_max = 32 << 20; |
| setrlimit(RLIMIT_MEMLOCK, &rlim); |
| rlim.rlim_cur = rlim.rlim_max = 136 << 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); |
| rlim.rlim_cur = rlim.rlim_max = 256; |
| setrlimit(RLIMIT_NOFILE, &rlim); |
| if (unshare(CLONE_NEWNS)) { |
| } |
| if (unshare(CLONE_NEWIPC)) { |
| } |
| if (unshare(0x02000000)) { |
| } |
| if (unshare(CLONE_NEWUTS)) { |
| } |
| if (unshare(CLONE_SYSVSEM)) { |
| } |
| } |
| |
| int wait_for_loop(int pid) |
| { |
| if (pid < 0) |
| exit(1); |
| int status = 0; |
| while (waitpid(-1, &status, __WALL) != pid) { |
| } |
| return WEXITSTATUS(status); |
| } |
| |
| 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)) |
| exit(1); |
| if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) |
| exit(1); |
| if (unshare(CLONE_NEWNET)) |
| exit(1); |
| if (mkdir("./syz-tmp", 0777)) |
| exit(1); |
| if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) |
| exit(1); |
| if (mkdir("./syz-tmp/newroot", 0777)) |
| exit(1); |
| if (mkdir("./syz-tmp/newroot/dev", 0700)) |
| exit(1); |
| unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; |
| if (mount("/dev", "./syz-tmp/newroot/dev", NULL, bind_mount_flags, NULL)) |
| exit(1); |
| if (mkdir("./syz-tmp/newroot/proc", 0700)) |
| exit(1); |
| if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL)) |
| exit(1); |
| if (mkdir("./syz-tmp/newroot/selinux", 0700)) |
| exit(1); |
| const char* selinux_path = "./syz-tmp/newroot/selinux"; |
| if (mount("/selinux", selinux_path, NULL, bind_mount_flags, NULL)) { |
| if (errno != ENOENT) |
| exit(1); |
| if (mount("/sys/fs/selinux", selinux_path, NULL, bind_mount_flags, NULL) && |
| errno != ENOENT) |
| exit(1); |
| } |
| if (mkdir("./syz-tmp/newroot/sys", 0700)) |
| exit(1); |
| if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL)) |
| exit(1); |
| if (mkdir("./syz-tmp/pivot", 0777)) |
| exit(1); |
| if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { |
| if (chdir("./syz-tmp")) |
| exit(1); |
| } else { |
| if (chdir("/")) |
| exit(1); |
| if (umount2("./pivot", MNT_DETACH)) |
| exit(1); |
| } |
| if (chroot("./newroot")) |
| exit(1); |
| if (chdir("/")) |
| exit(1); |
| 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)) |
| exit(1); |
| 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)) |
| exit(1); |
| loop(); |
| exit(1); |
| } |
| |
| #define SYZ_HAVE_SANDBOX_NAMESPACE 1 |
| static int do_sandbox_namespace(void) |
| { |
| int pid; |
| setup_common(); |
| real_uid = getuid(); |
| real_gid = getgid(); |
| mprotect(sandbox_stack, 4096, PROT_NONE); |
| pid = |
| clone(namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64], |
| CLONE_NEWUSER | CLONE_NEWPID, 0); |
| return wait_for_loop(pid); |
| } |
| |
| #define FS_IOC_SETFLAGS _IOW('f', 2, long) |
| static void remove_dir(const char* dir) |
| { |
| DIR* dp; |
| struct dirent* ep; |
| int iter = 0; |
| retry: |
| while (umount2(dir, MNT_DETACH) == 0) { |
| } |
| dp = opendir(dir); |
| if (dp == NULL) { |
| if (errno == EMFILE) { |
| exit(1); |
| } |
| exit(1); |
| } |
| 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); |
| while (umount2(filename, MNT_DETACH) == 0) { |
| } |
| struct stat st; |
| if (lstat(filename, &st)) |
| exit(1); |
| if (S_ISDIR(st.st_mode)) { |
| remove_dir(filename); |
| continue; |
| } |
| int i; |
| for (i = 0;; i++) { |
| if (unlink(filename) == 0) |
| break; |
| if (errno == EPERM) { |
| int fd = open(filename, O_RDONLY); |
| if (fd != -1) { |
| long flags = 0; |
| if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) |
| close(fd); |
| continue; |
| } |
| } |
| if (errno == EROFS) { |
| break; |
| } |
| if (errno != EBUSY || i > 100) |
| exit(1); |
| if (umount2(filename, MNT_DETACH)) |
| exit(1); |
| } |
| } |
| closedir(dp); |
| int i; |
| for (i = 0;; i++) { |
| if (rmdir(dir) == 0) |
| break; |
| if (i < 100) { |
| if (errno == EPERM) { |
| int fd = open(dir, O_RDONLY); |
| if (fd != -1) { |
| long flags = 0; |
| if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) |
| close(fd); |
| continue; |
| } |
| } |
| if (errno == EROFS) { |
| break; |
| } |
| if (errno == EBUSY) { |
| if (umount2(dir, MNT_DETACH)) |
| exit(1); |
| continue; |
| } |
| if (errno == ENOTEMPTY) { |
| if (iter < 100) { |
| iter++; |
| goto retry; |
| } |
| } |
| } |
| exit(1); |
| } |
| } |
| |
| static void kill_and_wait(int pid, int* status) |
| { |
| kill(-pid, SIGKILL); |
| kill(pid, SIGKILL); |
| int i; |
| for (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) { |
| } |
| } |
| |
| #define SYZ_HAVE_SETUP_TEST 1 |
| static void setup_test() |
| { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| } |
| |
| #define SYZ_HAVE_RESET_TEST 1 |
| static void reset_test() |
| { |
| int fd; |
| for (fd = 3; fd < 30; fd++) |
| close(fd); |
| } |
| |
| struct thread_t { |
| int created, call; |
| event_t ready, done; |
| }; |
| |
| static struct thread_t threads[16]; |
| static void execute_call(int call); |
| static int running; |
| |
| static void* thr(void* arg) |
| { |
| struct thread_t* th = (struct thread_t*)arg; |
| for (;;) { |
| event_wait(&th->ready); |
| event_reset(&th->ready); |
| execute_call(th->call); |
| __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); |
| event_set(&th->done); |
| } |
| return 0; |
| } |
| |
| static void execute_one(void) |
| { |
| int i, call, thread; |
| int collide = 0; |
| again: |
| for (call = 0; call < 4; call++) { |
| for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); |
| thread++) { |
| struct thread_t* th = &threads[thread]; |
| if (!th->created) { |
| th->created = 1; |
| event_init(&th->ready); |
| event_init(&th->done); |
| event_set(&th->done); |
| thread_start(thr, th); |
| } |
| if (!event_isset(&th->done)) |
| continue; |
| event_reset(&th->done); |
| th->call = call; |
| __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); |
| event_set(&th->ready); |
| if (collide && (call % 2) == 0) |
| break; |
| event_timedwait(&th->done, 45); |
| break; |
| } |
| } |
| for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) |
| sleep_ms(1); |
| if (!collide) { |
| collide = 1; |
| goto again; |
| } |
| } |
| |
| static void execute_one(void); |
| |
| #define WAIT_FLAGS __WALL |
| |
| static void loop(void) |
| { |
| int iter; |
| for (iter = 0;; 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); |
| setup_test(); |
| execute_one(); |
| reset_test(); |
| 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 < 5 * 1000) |
| continue; |
| kill_and_wait(pid, &status); |
| break; |
| } |
| remove_dir(cwdbuf); |
| } |
| } |
| |
| uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; |
| |
| void execute_call(int call) |
| { |
| long res; |
| switch (call) { |
| case 0: |
| memcpy((void*)0x200000c0, "/dev/kvm", 9); |
| res = syscall(__NR_openat, 0xffffffffffffff9c, 0x200000c0, 0, 0); |
| if (res != -1) |
| r[0] = res; |
| break; |
| case 1: |
| res = syscall(__NR_ioctl, r[0], 0xae01, 0); |
| if (res != -1) |
| r[1] = res; |
| break; |
| case 2: |
| res = syscall(__NR_ioctl, r[1], 0xae41, 0); |
| if (res != -1) |
| r[2] = res; |
| break; |
| case 3: |
| *(uint32_t*)0x20000000 = 0xa3; |
| *(uint32_t*)0x20000004 = 0; |
| *(uint64_t*)0x20000008 = 0x706000; |
| *(uint64_t*)0x20000010 = 0; |
| *(uint64_t*)0x20000018 = 0; |
| *(uint64_t*)0x20000020 = 0; |
| *(uint8_t*)0x20000028 = 0; |
| *(uint8_t*)0x20000029 = 0; |
| *(uint8_t*)0x2000002a = 0; |
| *(uint8_t*)0x2000002b = 0; |
| *(uint8_t*)0x2000002c = 0; |
| *(uint8_t*)0x2000002d = 0; |
| *(uint8_t*)0x2000002e = 0; |
| *(uint8_t*)0x2000002f = 0; |
| *(uint8_t*)0x20000030 = 0; |
| *(uint8_t*)0x20000031 = 0; |
| *(uint8_t*)0x20000032 = 0; |
| *(uint8_t*)0x20000033 = 0; |
| *(uint8_t*)0x20000034 = 0; |
| *(uint8_t*)0x20000035 = 0; |
| *(uint8_t*)0x20000036 = 0; |
| *(uint8_t*)0x20000037 = 0; |
| *(uint8_t*)0x20000038 = 0; |
| *(uint8_t*)0x20000039 = 0; |
| *(uint8_t*)0x2000003a = 0; |
| *(uint8_t*)0x2000003b = 0; |
| *(uint8_t*)0x2000003c = 0; |
| *(uint8_t*)0x2000003d = 0; |
| *(uint8_t*)0x2000003e = 0; |
| *(uint8_t*)0x2000003f = 0; |
| *(uint8_t*)0x20000040 = 0; |
| *(uint8_t*)0x20000041 = 0; |
| *(uint8_t*)0x20000042 = 0; |
| *(uint8_t*)0x20000043 = 0; |
| *(uint8_t*)0x20000044 = 0; |
| *(uint8_t*)0x20000045 = 0; |
| *(uint8_t*)0x20000046 = 0; |
| *(uint8_t*)0x20000047 = 0; |
| *(uint8_t*)0x20000048 = 0; |
| *(uint8_t*)0x20000049 = 0; |
| *(uint8_t*)0x2000004a = 0; |
| *(uint8_t*)0x2000004b = 0; |
| *(uint8_t*)0x2000004c = 0; |
| *(uint8_t*)0x2000004d = 0; |
| *(uint8_t*)0x2000004e = 0; |
| *(uint8_t*)0x2000004f = 0; |
| *(uint8_t*)0x20000050 = 0; |
| *(uint8_t*)0x20000051 = 0; |
| *(uint8_t*)0x20000052 = 0; |
| *(uint8_t*)0x20000053 = 0; |
| *(uint8_t*)0x20000054 = 0; |
| *(uint8_t*)0x20000055 = 0; |
| *(uint8_t*)0x20000056 = 0; |
| *(uint8_t*)0x20000057 = 0; |
| *(uint8_t*)0x20000058 = 0; |
| *(uint8_t*)0x20000059 = 0; |
| *(uint8_t*)0x2000005a = 0; |
| *(uint8_t*)0x2000005b = 0; |
| *(uint8_t*)0x2000005c = 0; |
| *(uint8_t*)0x2000005d = 0; |
| *(uint8_t*)0x2000005e = 0; |
| *(uint8_t*)0x2000005f = 0; |
| *(uint8_t*)0x20000060 = 0; |
| *(uint8_t*)0x20000061 = 0; |
| *(uint8_t*)0x20000062 = 0; |
| *(uint8_t*)0x20000063 = 0; |
| *(uint8_t*)0x20000064 = 0; |
| *(uint8_t*)0x20000065 = 0; |
| *(uint8_t*)0x20000066 = 0; |
| *(uint8_t*)0x20000067 = 0; |
| syscall(__NR_ioctl, r[2], 0x4068aea3, 0x20000000); |
| break; |
| } |
| } |
| int main(void) |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| use_temporary_dir(); |
| do_sandbox_namespace(); |
| return 0; |
| } |