linux-kernel - [PATCH 5.10 270/717] net: sunrpc: Fix snprintf return value check in do_xprt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201228125033.950359662@linuxfoundation.org>
Date:   Mon, 28 Dec 2020 13:44:28 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Fedor Tokarev <ftokarev@...il.com>,
        Trond Myklebust <trond.myklebust@...merspace.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 270/717] net: sunrpc: Fix snprintf return value check in do_xprt_debugfs

From: Fedor Tokarev <ftokarev@...il.com>

[ Upstream commit 35a6d396721e28ba161595b0fc9e8896c00399bb ]

'snprintf' returns the number of characters which would have been written
if enough space had been available, excluding the terminating null byte.
Thus, the return value of 'sizeof(buf)' means that the last character
has been dropped.

Signed-off-by: Fedor Tokarev <ftokarev@...il.com>
Fixes: 2f34b8bfae19 ("SUNRPC: add links for all client xprts to debugfs")
Signed-off-by: Trond Myklebust <trond.myklebust@...merspace.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 net/sunrpc/debugfs.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/sunrpc/debugfs.c b/net/sunrpc/debugfs.c
index fd9bca2427242..56029e3af6ff0 100644
--- a/net/sunrpc/debugfs.c
+++ b/net/sunrpc/debugfs.c
@@ -128,13 +128,13 @@ static int do_xprt_debugfs(struct rpc_clnt *clnt, struct rpc_xprt *xprt, void *n
 		return 0;
 	len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
 		       xprt->debugfs->d_name.name);
-	if (len > sizeof(name))
+	if (len >= sizeof(name))
 		return -1;
 	if (*nump == 0)
 		strcpy(link, "xprt");
 	else {
 		len = snprintf(link, sizeof(link), "xprt%d", *nump);
-		if (len > sizeof(link))
+		if (len >= sizeof(link))
 			return -1;
 	}
 	debugfs_create_symlink(link, clnt->cl_debugfs, name);
-- 
2.27.0