From: Josef Bacik <jbacik@fusionio.com>
Date: Wed, 24 Apr 2013 20:38:50 +0000 (-0400)
Subject: Btrfs: don't panic if we're trying to drop too many refs
X-Git-Tag: firefly_0821_release~3680^2~310^2~33
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=32b0253803bf8e384a37a70f2dfffb2056e7d087;p=firefly-linux-kernel-4.4.55.git

Btrfs: don't panic if we're trying to drop too many refs

This is just obnoxious.  Just print a message, abort the transaction, and return
an error.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
---

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 6526f1faf6c2..f8a5652b0c43 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5596,7 +5596,13 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 	}
 
 	refs = btrfs_extent_refs(leaf, ei);
-	BUG_ON(refs < refs_to_drop);
+	if (refs < refs_to_drop) {
+		btrfs_err(info, "trying to drop %d refs but we only have %Lu "
+			  "for bytenr %Lu\n", refs_to_drop, refs, bytenr);
+		ret = -EINVAL;
+		btrfs_abort_transaction(trans, extent_root, ret);
+		goto out;
+	}
 	refs -= refs_to_drop;
 
 	if (refs > 0) {