diff mbox

[backport,request] netfilter: ipt_ULOG: fix info leaks

Message ID 20140701182013.GM26742@32k.org
State Not Applicable, archived
Delegated to: David Miller
Headers show

Commit Message

Jan Tore Morken July 1, 2014, 6:20 p.m. UTC 
Hi,

I mistakenly sent this request to the stable list before being made
aware that it belonged here. Sorry to anyone reading this for the
second time.

I'd like to request that the commit below is backported to stable. The
commit fixes an old memory disclosure issue, and has already spent
some time in mainline.

Thanks!
diff mbox

Patch

===

From 278f2b3e2af5f32ea1afe34fa12a2518153e6e49 Mon Sep 17 00:00:00 2001
From: Mathias Krause <minipli@googlemail.com>
Date: Mon, 30 Sep 2013 22:05:08 +0200
Subject: [PATCH] netfilter: ipt_ULOG: fix info leaks

The ulog messages leak heap bytes by the means of padding bytes and
incompletely filled string arrays. Fix those by memset(0)'ing the
whole struct before filling it.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv4/netfilter/ipt_ULOG.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c
index cbc2215..9cb993c 100644
--- a/net/ipv4/netfilter/ipt_ULOG.c
+++ b/net/ipv4/netfilter/ipt_ULOG.c
@@ -220,6 +220,7 @@  static void ipt_ulog_packet(struct net *net,
 	ub->qlen++;
 
 	pm = nlmsg_data(nlh);
+	memset(pm, 0, sizeof(*pm));
 
 	/* We might not have a timestamp, get one */
 	if (skb->tstamp.tv64 == 0)
@@ -238,8 +239,6 @@  static void ipt_ulog_packet(struct net *net,
 	}
 	else if (loginfo->prefix[0] != '\0')
 		strncpy(pm->prefix, loginfo->prefix, sizeof(pm->prefix));
-	else
-		*(pm->prefix) = '\0';
 
 	if (in && in->hard_header_len > 0 &&
 	    skb->mac_header != skb->network_header &&
@@ -251,13 +250,9 @@  static void ipt_ulog_packet(struct net *net,
 
 	if (in)
 		strncpy(pm->indev_name, in->name, sizeof(pm->indev_name));
-	else
-		pm->indev_name[0] = '\0';
 
 	if (out)
 		strncpy(pm->outdev_name, out->name, sizeof(pm->outdev_name));
-	else
-		pm->outdev_name[0] = '\0';
 
 	/* copy_len <= skb->len, so can't fail. */
 	if (skb_copy_bits(skb, 0, pm->payload, copy_len) < 0)