diff options
| author | Josef Bacik <josef@toxicpanda.com> | 2020-01-24 17:32:36 +0300 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-03-23 19:01:28 +0300 |
| commit | 04734e844894ccdfcb907d10eec1433e19d4918a (patch) | |
| tree | 9c495719601c8de74c4bccfd21d1d1859b5de16a /fs/btrfs/ioctl.c | |
| parent | b8a49ae1913f1befdbd477f805e99cb61d7971df (diff) | |
| download | linux-04734e844894ccdfcb907d10eec1433e19d4918a.tar.xz | |
btrfs: hold a ref on the root in btrfs_ioctl_get_subvol_info
We look up whatever root userspace has given us, we need to hold a ref
throughout this operation. Use 'root' only for the on fs root and not as
a temporary variable elsewhere.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 7e1af2d46dd2..0aa47bc3e172 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2681,6 +2681,10 @@ static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp) root = btrfs_get_fs_root(fs_info, &key, true); if (IS_ERR(root)) { ret = PTR_ERR(root); + goto out_free; + } + if (!btrfs_grab_fs_root(root)) { + ret = -ENOENT; goto out; } root_item = &root->root_item; @@ -2714,16 +2718,14 @@ static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp) if (key.objectid != BTRFS_FS_TREE_OBJECTID) { /* Search root tree for ROOT_BACKREF of this subvolume */ - root = fs_info->tree_root; - key.type = BTRFS_ROOT_BACKREF_KEY; key.offset = 0; - ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); if (ret < 0) { goto out; } else if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { - ret = btrfs_next_leaf(root, path); + ret = btrfs_next_leaf(fs_info->tree_root, path); if (ret < 0) { goto out; } else if (ret > 0) { @@ -2758,6 +2760,8 @@ static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp) ret = -EFAULT; out: + btrfs_put_fs_root(root); +out_free: btrfs_free_path(path); kzfree(subvol_info); return ret; |