diff options
| -rw-r--r-- | fs/btrfs/ioctl.c | 42 |
1 files changed, 28 insertions, 14 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 13ed1c9534cc..17facea6a51c 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1521,29 +1521,40 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file, u64 flags; int ret = 0; - if (root->fs_info->sb->s_flags & MS_RDONLY) - return -EROFS; + ret = mnt_want_write_file(file); + if (ret) + goto out; - if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) - return -EINVAL; + if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) { + ret = -EINVAL; + goto out_drop_write; + } - if (copy_from_user(&flags, arg, sizeof(flags))) - return -EFAULT; + if (copy_from_user(&flags, arg, sizeof(flags))) { + ret = -EFAULT; + goto out_drop_write; + } - if (flags & BTRFS_SUBVOL_CREATE_ASYNC) - return -EINVAL; + if (flags & BTRFS_SUBVOL_CREATE_ASYNC) { + ret = -EINVAL; + goto out_drop_write; + } - if (flags & ~BTRFS_SUBVOL_RDONLY) - return -EOPNOTSUPP; + if (flags & ~BTRFS_SUBVOL_RDONLY) { + ret = -EOPNOTSUPP; + goto out_drop_write; + } - if (!inode_owner_or_capable(inode)) - return -EACCES; + if (!inode_owner_or_capable(inode)) { + ret = -EACCES; + goto out_drop_write; + } down_write(&root->fs_info->subvol_sem); /* nothing to do */ if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) - goto out; + goto out_drop_sem; root_flags = btrfs_root_flags(&root->root_item); if (flags & BTRFS_SUBVOL_RDONLY) @@ -1566,8 +1577,11 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file, out_reset: if (ret) btrfs_set_root_flags(&root->root_item, root_flags); -out: +out_drop_sem: up_write(&root->fs_info->subvol_sem); +out_drop_write: + mnt_drop_write_file(file); +out: return ret; } |
