btrfs: unset reloc control if we fail to recover

If we fail to load an fs root, or fail to start a transaction we can
bail without unsetting the reloc control, which leads to problems later
when we free the reloc control but still have it attached to the file
system.

In the normal path we'll end up calling unset_reloc_control() twice, but
all it does is set fs_info->reloc_control = NULL, and we can only have
one balance at a time so it's not racey.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index d7f3d2197fa15891e09b789abbc5bc7c1cdee52c..78537541059b7d12ada313a1f9f174441a595c61 100644 (file)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4460,9 +4460,8 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 
        trans = btrfs_join_transaction(rc->extent_root);
        if (IS_ERR(trans)) {
-               unset_reloc_control(rc);
                err = PTR_ERR(trans);
-               goto out_free;
+               goto out_unset;
        }
 
        rc->merge_reloc_tree = 1;
@@ -4482,7 +4481,7 @@ int btrfs_recover_relocation(struct btrfs_root *root)
                if (IS_ERR(fs_root)) {
                        err = PTR_ERR(fs_root);
                        list_add_tail(&reloc_root->root_list, &reloc_roots);
-                       goto out_free;
+                       goto out_unset;
                }
 
                err = __add_reloc_root(reloc_root);
@@ -4493,7 +4492,7 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 
        err = btrfs_commit_transaction(trans);
        if (err)
-               goto out_free;
+               goto out_unset;
 
        merge_reloc_roots(rc);
 
@@ -4509,7 +4508,8 @@ int btrfs_recover_relocation(struct btrfs_root *root)
        ret = clean_dirty_subvols(rc);
        if (ret < 0 && !err)
                err = ret;
-out_free:
+out_unset:
+       unset_reloc_control(rc);
        kfree(rc);
 out:
        if (!list_empty(&reloc_roots))