From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Sun, 18 Feb 2024 21:16:53 +0000 (+0100)
Subject: NFS: Fix an off by one in root_nfs_cat()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=698ad1a538da0b6bf969cfee630b4e3a026afb87;p=linux.git

NFS: Fix an off by one in root_nfs_cat()

The intent is to check if 'dest' is truncated or not. So, >= should be
used instead of >, because strlcat() returns the length of 'dest' and 'src'
excluding the trailing NULL.

Fixes: 56463e50d1fc ("NFS: Use super.c for NFSROOT mount option parsing")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---

diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index 7600100ba26f0..432612d224374 100644
--- a/fs/nfs/nfsroot.c
+++ b/fs/nfs/nfsroot.c
@@ -175,10 +175,10 @@ static int __init root_nfs_cat(char *dest, const char *src,
 	size_t len = strlen(dest);
 
 	if (len && dest[len - 1] != ',')
-		if (strlcat(dest, ",", destlen) > destlen)
+		if (strlcat(dest, ",", destlen) >= destlen)
 			return -1;
 
-	if (strlcat(dest, src, destlen) > destlen)
+	if (strlcat(dest, src, destlen) >= destlen)
 		return -1;
 	return 0;
 }