From: David Sterba <dsterba@suse.com>
Date: Wed, 24 Jan 2024 14:37:59 +0000 (+0100)
Subject: btrfs: handle invalid extent item reference found in check_committed_ref()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=a4259b6c191119f270561c75eee840363f697c04;p=linux.git

btrfs: handle invalid extent item reference found in check_committed_ref()

The check_committed_ref() helper looks up an extent item by a key,
allowing to do an inexact search when key->offset is -1.  It's never
expected to find such item, as it would break the allowed range of a
extent item offset.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 49437ad7248de..bd1645089d499 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2396,7 +2396,14 @@ static noinline int check_committed_ref(struct btrfs_root *root,
 	ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
 	if (ret < 0)
 		goto out;
-	BUG_ON(ret == 0); /* Corruption */
+	if (ret == 0) {
+		/*
+		 * Key with offset -1 found, there would have to exist an extent
+		 * item with such offset, but this is out of the valid range.
+		 */
+		ret = -EUCLEAN;
+		goto out;
+	}
 
 	ret = -ENOENT;
 	if (path->slots[0] == 0)