[PATCH 4.19 38/58] btrfs: fixup error handling in fixup_inode_link_counts

From: Greg Kroah-Hartman
Date: Tue Jun 08 2021 - 14:40:28 EST


From: Josef Bacik <josef@xxxxxxxxxxxxxx>

commit 011b28acf940eb61c000059dd9e2cfcbf52ed96b upstream.

This function has the following pattern

while (1) {
ret = whatever();
if (ret)
goto out;
}
ret = 0
out:
return ret;

However several places in this while loop we simply break; when there's
a problem, thus clearing the return value, and in one case we do a
return -EIO, and leak the memory for the path.

Fix this by re-arranging the loop to deal with ret == 1 coming from
btrfs_search_slot, and then simply delete the

ret = 0;
out:

bit so everybody can break if there is an error, which will allow for
proper error handling to occur.

CC: stable@xxxxxxxxxxxxxxx # 4.4+
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/tree-log.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -1699,6 +1699,7 @@ static noinline int fixup_inode_link_cou
break;

if (ret == 1) {
+ ret = 0;
if (path->slots[0] == 0)
break;
path->slots[0]--;
@@ -1711,17 +1712,19 @@ static noinline int fixup_inode_link_cou

ret = btrfs_del_item(trans, root, path);
if (ret)
- goto out;
+ break;

btrfs_release_path(path);
inode = read_one_inode(root, key.offset);
- if (!inode)
- return -EIO;
+ if (!inode) {
+ ret = -EIO;
+ break;
+ }

ret = fixup_inode_link_count(trans, root, inode);
iput(inode);
if (ret)
- goto out;
+ break;

/*
* fixup on a directory may create new entries,
@@ -1730,8 +1733,6 @@ static noinline int fixup_inode_link_cou
*/
key.offset = (u64)-1;
}
- ret = 0;
-out:
btrfs_release_path(path);
return ret;
}