netdev - [PATCH net-next] sctp: also point GSO head

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:	Sat, 23 Jul 2016 00:33:44 -0300
From:	Marcelo Ricardo Leitner <marcelo.leitner@...il.com>
To:	netdev@...r.kernel.org
Cc:	Vlad Yasevich <vyasevich@...il.com>,
	Neil Horman <nhorman@...driver.com>, linux-sctp@...r.kernel.org
Subject: [PATCH net-next] sctp: also point GSO head_skb to the sk when it's available

The head skb for GSO packets won't travel through the inner depths of
SCTP stack as it doesn't contain any chunks on it. That means skb->sk
doesn't get set and then when sctp_recvmsg() calls
sctp_inet6_skb_msgname() on the head_skb it panics, as this last needs
to check flags at the socket (sp->v4mapped).

The fix is to initialize skb->sk for th head skb once we are able to do
it. That is, when the first chunk is processed.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@...il.com>
---
 net/sctp/ulpevent.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/sctp/ulpevent.c b/net/sctp/ulpevent.c
index f6219b164b42c821c3e6f626731e97dd712c957c..1bc4f71aaba860776a0a6e4b664ef1c3a0f8af37 100644
--- a/net/sctp/ulpevent.c
+++ b/net/sctp/ulpevent.c
@@ -91,6 +91,7 @@ int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event)
 static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
 					   const struct sctp_association *asoc)
 {
+	struct sctp_chunk *chunk = event->chunk;
 	struct sk_buff *skb;
 
 	/* Cast away the const, as we are just wanting to
@@ -101,6 +102,8 @@ static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
 	event->asoc = (struct sctp_association *)asoc;
 	atomic_add(event->rmem_len, &event->asoc->rmem_alloc);
 	sctp_skb_set_owner_r(skb, asoc->base.sk);
+	if (chunk && chunk->head_skb && !chunk->head_skb->sk)
+		chunk->head_skb->sk = asoc->base.sk;
 }
 
 /* A simple destructor to give up the reference to the association. */
-- 
2.7.4