From 14a1c1dc56954fad21b57a52ba8fef6b28050524 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Fri, 10 Apr 2020 17:06:01 +0800 Subject: [PATCH] xfrm: allow to accept packets with ipv6 NEXTHDR_HOP in xfrm_input commit afcaf61be9d1dbdee5ec186d1dcc67b6b692180f upstream. For beet mode, when it's ipv6 inner address with nexthdrs set, the packet format might be: ---------------------------------------------------- | outer | | dest | | | ESP | ESP | | IP hdr | ESP | opts.| TCP | Data | Trailer | ICV | ---------------------------------------------------- The nexthdr from ESP could be NEXTHDR_HOP(0), so it should continue processing the packet when nexthdr returns 0 in xfrm_input(). Otherwise, when ipv6 nexthdr is set, the packet will be dropped. I don't see any error cases that nexthdr may return 0. So fix it by removing the check for nexthdr == 0. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c index 2c86a2fc3915..7a8474547791 100644 --- a/net/xfrm/xfrm_input.c +++ b/net/xfrm/xfrm_input.c @@ -643,7 +643,7 @@ resume: dev_put(skb->dev); spin_lock(&x->lock); - if (nexthdr <= 0) { + if (nexthdr < 0) { if (nexthdr == -EBADMSG) { xfrm_audit_state_icvfail(x, skb, x->type->proto);