diff mbox series

NFS: Fix an off by one in root_nfs_cat()

Message ID 7f97bb62c4e8137c5d7f7a7a30789440a5102b3f.1698183837.git.christophe.jaillet@wanadoo.fr
State New
Headers
Series NFS: Fix an off by one in root_nfs_cat() |

Commit Message

Christophe JAILLET Oct. 24, 2023, 9:47 p.m. UTC 
  The intent is to check if the '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>
---
 fs/nfs/nfsroot.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Benjamin Coddington Oct. 25, 2023, 12:34 p.m. UTC | #1 
On 24 Oct 2023, at 17:47, Christophe JAILLET wrote:

> The intent is to check if the '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>

Minor typo in the body: >+ should be >=, otherwise looks right.

Reviewed-by: Benjamin Coddington <bcodding@redhat.com>

Ben
diff mbox series

Patch

diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index 7600100ba26f..432612d22437 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;
 }