[PATCH] Clear ulog message to prevent leaking uninitializied memory to user

[PATCH] Clear ulog message to prevent leaking uninitializied memory to user

[Mark Leander]

ipt_ulog_packet() did not properly blank the char[] members
indev_name, outdev_name, prefix and mac of struct ulog_packet_msg.
This leaks uninitialized kernel memory to user space in the form
of netlink NFLOG broadcasts. This change clears the whole structure
initially to avoid this.

Signed-off-by: Mark Leander <mark.leander@topicbranch.net>
---
 net/ipv4/netfilter/ipt_ULOG.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c
index 446e0f4..07b36b0 100644
--- a/net/ipv4/netfilter/ipt_ULOG.c
+++ b/net/ipv4/netfilter/ipt_ULOG.c
@@ -204,6 +204,7 @@ static void ipt_ulog_packet(unsigned int hooknum,
 	ub->qlen++;
 
 	pm = NLMSG_DATA(nlh);
+	memset(pm, 0, sizeof(*pm));
 
 	/* We might not have a timestamp, get one */
 	if (skb->tstamp.tv64 == 0)
-- 
1.7.0.4