netdev - [net-next] tipc: add NULL pointer check

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-next>] [day] [month] [year] [list]

Date:   Wed,  3 Apr 2019 13:05:04 +0700
From:   Hoang Le <hoang.h.le@...tech.com.au>
To:     jon.maloy@...csson.com, maloy@...jonn.com, ying.xue@...driver.com,
        tipc-discussion@...ts.sourceforge.net, netdev@...r.kernel.org
Subject: [net-next] tipc: add NULL pointer check

skb somehow dequeued out of inputq before processing, it causes to
NULL pointer and kernel crashed.

Add checking skb valid before using.

Fixes: c55c8edafa9 ("tipc: smooth change between replicast and broadcast")
Reported-by: Tuong Lien Tong <tuong.t.lien@...tech.com.au>
Acked-by: Ying Xue <ying.xue@...driver.com>
Signed-off-by: Hoang Le <hoang.h.le@...tech.com.au>
---
 net/tipc/bcast.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 76e14dc08bb9..6c997d4a6218 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -769,6 +769,9 @@ void tipc_mcast_filter_msg(struct net *net, struct sk_buff_head *defq,
 	u32 node, port;
 
 	skb = skb_peek(inputq);
+	if (!skb)
+		return;
+
 	hdr = buf_msg(skb);
 
 	if (likely(!msg_is_syn(hdr) && skb_queue_empty(defq)))
-- 
2.17.1