From 7aabe9d9e0273060dbae7e5cccd1dafe59c701c3 Mon Sep 17 00:00:00 2001
From: "Alexander V. Chernikov" <melifaro@FreeBSD.org>
Date: Mon, 10 Oct 2011 09:33:07 +0000
Subject: [PATCH] Free mbuf in case when protocol in unknown in
 ng_ipfw_rcvdata(). This change fixes (theoretically) possible mbuf leak
 introduced in r225586. Reorder code a bit and change return codes to be more
 specific

Reviewed by:	glebius
Approved by:    kib (mentor)
---
 sys/netgraph/ng_ipfw.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/sys/netgraph/ng_ipfw.c b/sys/netgraph/ng_ipfw.c
index 4f1bc0ee94d..117c608dfd7 100644
--- a/sys/netgraph/ng_ipfw.c
+++ b/sys/netgraph/ng_ipfw.c
@@ -242,7 +242,7 @@ ng_ipfw_rcvdata(hook_p hook, item_p item)
 
 	if (m->m_len < sizeof(struct ip) &&
 	    (m = m_pullup(m, sizeof(struct ip))) == NULL)
-		return (EINVAL);
+		return (ENOBUFS);
 
 	ip = mtod(m, struct ip *);
 
@@ -252,18 +252,14 @@ ng_ipfw_rcvdata(hook_p hook, item_p item)
 #ifdef INET
 		case IPVERSION:
 			ip_input(m);
-			break;
+			return (0);
 #endif
 #ifdef INET6
 		case IPV6_VERSION >> 4:
 			ip6_input(m);
-			break;
+			return (0);
 #endif
-		default:
-			NG_FREE_M(m);
-			return (EINVAL);
 		}
-		return (0);
 	} else {
 		switch (ip->ip_v) {
 #ifdef INET
@@ -277,10 +273,12 @@ ng_ipfw_rcvdata(hook_p hook, item_p item)
 			return (ip6_output(m, NULL, NULL, 0, NULL,
 			    NULL, NULL));
 #endif
-		default:
-			return (EINVAL);
 		}
 	}
+
+	/* unknown IP protocol version */
+	NG_FREE_M(m);
+	return (EPROTONOSUPPORT);
 }
 
 static int