From 374a8fcb4a4adbd9b2fc99ccd742d54a61f86b4f Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Mon, 24 Jun 2024 20:40:37 +0800 Subject: [PATCH] NFS: Fix an off by one in root_nfs_cat() stable inclusion from stable-v4.19.311 commit 9bb320c5cea50e7fa82a477743a6a0546eaa37b3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IA7XXI CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9bb320c5cea50e7fa82a477743a6a0546eaa37b3 -------------------------------- [ Upstream commit 698ad1a538da0b6bf969cfee630b4e3a026afb87 ] 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 Reviewed-by: Benjamin Coddington Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin Signed-off-by: Wang Zhaolong --- fs/nfs/nfsroot.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c index effaa4247b91..c0f2e1751c33 100644 --- a/fs/nfs/nfsroot.c +++ b/fs/nfs/nfsroot.c @@ -169,10 +169,10 @@ 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; } -- Gitee