x86: switch cp_stat64() to unsafe_put_user()
authorAl Viro <viro@zeniv.linux.org.uk>
Sun, 16 Feb 2020 22:32:57 +0000 (17:32 -0500)
committerAl Viro <viro@zeniv.linux.org.uk>
Wed, 3 Jun 2020 20:59:21 +0000 (16:59 -0400)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
arch/x86/kernel/sys_ia32.c

index ab03fede1422c86cc5afe5640f7b6ba20dd6f29b..f8d65c99feb80fa6f007ce4075e257d1cfb24a87 100644 (file)
@@ -135,26 +135,30 @@ static int cp_stat64(struct stat64 __user *ubuf, struct kstat *stat)
        typeof(ubuf->st_gid) gid = 0;
        SET_UID(uid, from_kuid_munged(current_user_ns(), stat->uid));
        SET_GID(gid, from_kgid_munged(current_user_ns(), stat->gid));
-       if (!access_ok(ubuf, sizeof(struct stat64)) ||
-           __put_user(huge_encode_dev(stat->dev), &ubuf->st_dev) ||
-           __put_user(stat->ino, &ubuf->__st_ino) ||
-           __put_user(stat->ino, &ubuf->st_ino) ||
-           __put_user(stat->mode, &ubuf->st_mode) ||
-           __put_user(stat->nlink, &ubuf->st_nlink) ||
-           __put_user(uid, &ubuf->st_uid) ||
-           __put_user(gid, &ubuf->st_gid) ||
-           __put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev) ||
-           __put_user(stat->size, &ubuf->st_size) ||
-           __put_user(stat->atime.tv_sec, &ubuf->st_atime) ||
-           __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec) ||
-           __put_user(stat->mtime.tv_sec, &ubuf->st_mtime) ||
-           __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec) ||
-           __put_user(stat->ctime.tv_sec, &ubuf->st_ctime) ||
-           __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec) ||
-           __put_user(stat->blksize, &ubuf->st_blksize) ||
-           __put_user(stat->blocks, &ubuf->st_blocks))
+       if (!user_write_access_begin(ubuf, sizeof(struct stat64)))
                return -EFAULT;
+       unsafe_put_user(huge_encode_dev(stat->dev), &ubuf->st_dev, Efault);
+       unsafe_put_user(stat->ino, &ubuf->__st_ino, Efault);
+       unsafe_put_user(stat->ino, &ubuf->st_ino, Efault);
+       unsafe_put_user(stat->mode, &ubuf->st_mode, Efault);
+       unsafe_put_user(stat->nlink, &ubuf->st_nlink, Efault);
+       unsafe_put_user(uid, &ubuf->st_uid, Efault);
+       unsafe_put_user(gid, &ubuf->st_gid, Efault);
+       unsafe_put_user(huge_encode_dev(stat->rdev), &ubuf->st_rdev, Efault);
+       unsafe_put_user(stat->size, &ubuf->st_size, Efault);
+       unsafe_put_user(stat->atime.tv_sec, &ubuf->st_atime, Efault);
+       unsafe_put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec, Efault);
+       unsafe_put_user(stat->mtime.tv_sec, &ubuf->st_mtime, Efault);
+       unsafe_put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec, Efault);
+       unsafe_put_user(stat->ctime.tv_sec, &ubuf->st_ctime, Efault);
+       unsafe_put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec, Efault);
+       unsafe_put_user(stat->blksize, &ubuf->st_blksize, Efault);
+       unsafe_put_user(stat->blocks, &ubuf->st_blocks, Efault);
+       user_access_end();
        return 0;
+Efault:
+       user_write_access_end();
+       return -EFAULT;
 }
 
 COMPAT_SYSCALL_DEFINE2(ia32_stat64, const char __user *, filename,