From: Al Viro <viro@ZenIV.linux.org.uk>
Date: Fri, 4 Mar 2011 17:15:18 +0000 (+0000)
Subject: btrfs: check link counter overflow in link(2)
X-Git-Tag: firefly_0821_release~7613^2~1434^2~41
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=c055e99eea6e4f614267632fac546e7896c0227b;p=firefly-linux-kernel-4.4.55.git

btrfs: check link counter overflow in link(2)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4822b3132784..04babaf31a33 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4837,6 +4837,9 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 	if (root->objectid != BTRFS_I(inode)->root->objectid)
 		return -EXDEV;
 
+	if (inode->i_nlink == ~0U)
+		return -EMLINK;
+
 	btrfs_inc_nlink(inode);
 	inode->i_ctime = CURRENT_TIME;