[PATCH AUTOSEL 5.4 188/330] btrfs: free the reloc_control in a consistent way

Sasha Levin
2020-09-18T02:05:08Z

From: Josef Bacik <josef@toxicpanda.com>

[ Upstream commit 1a0afa0ecfc4dbc8d7583d03cafd3f68f781df0c ]

If we have an error while processing the reloc roots we could leak roots
that were added to rc->reloc_roots before we hit the error. We could
have also not removed the reloc tree mapping from our rb_tree, so clean
up any remaining nodes in the reloc root rb_tree.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ use rbtree_postorder_for_each_entry_safe ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/btrfs/relocation.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 1313506a7ecb5..ece53d2f55ae3 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4354,6 +4354,18 @@ static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info)
return rc;
}

+static void free_reloc_control(struct reloc_control *rc)
+{
+ struct mapping_node *node, *tmp;
+
+ free_reloc_roots(&rc->reloc_roots);
+ rbtree_postorder_for_each_entry_safe(node, tmp,
+ &rc->reloc_root_tree.rb_root, rb_node)
+ kfree(node);
+
+ kfree(rc);
+}
+
/*
* Print the block group being relocated
*/
@@ -4486,7 +4498,7 @@ out:
btrfs_dec_block_group_ro(rc->block_group);
iput(rc->data_inode);
btrfs_put_block_group(rc->block_group);
- kfree(rc);
+ free_reloc_control(rc);
return err;
}

@@ -4659,7 +4671,7 @@ out_clean:
err = ret;
out_unset:
unset_reloc_control(rc);
- kfree(rc);
+ free_reloc_control(rc);
out:
if (!list_empty(&reloc_roots))
free_reloc_roots(&reloc_roots);
--
2.25.1