From 4b654acdae850f48b8250b9a578a4eaa518c7a6f Mon Sep 17 00:00:00 2001
From: Qu Wenruo <wqu@suse.com>
Date: Thu, 10 Oct 2019 10:39:26 +0800
Patch-mainline: v5.4-rc5
Git-commit: 4b654acdae850f48b8250b9a578a4eaa518c7a6f
References: bsc#1155178
Subject: [PATCH] btrfs: block-group: Fix a memory leak due to missing
 btrfs_put_block_group()

In btrfs_read_block_groups(), if we have an invalid block group which
has mixed type (DATA|METADATA) while the fs doesn't have MIXED_GROUPS
feature, we error out without freeing the block group cache.

This patch will add the missing btrfs_put_block_group() to prevent
memory leak.

Note for stable backports: the file to patch in versions <= 5.3 is
fs/btrfs/extent-tree.c

Fixes: 49303381f19a ("Btrfs: bail out if block group has different mixed flag")
CC: stable@vger.kernel.org # 4.9+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/block-group.c |    1 +
 1 file changed, 1 insertion(+)

--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1589,6 +1589,7 @@ int btrfs_read_block_groups(struct btrfs
 			btrfs_err(info,
 "bg %llu is a mixed block group but filesystem hasn't enabled mixed block groups",
 				  cache->key.objectid);
+			btrfs_put_block_group(cache);
 			ret = -EINVAL;
 			goto error;
 		}