netdev - [PATCH net,v2] ip_gre: fix msg_name parsing for recvfrom/recvmsg

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 16 Dec 2013 11:02:09 +0200
From:	Timo Teräs <timo.teras@....fi>
To:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org
Cc:	Timo Teräs <timo.teras@....fi>,
	Pravin B Shelar <pshelar@...ira.com>
Subject: [PATCH net,v2] ip_gre: fix msg_name parsing for recvfrom/recvmsg

ipgre_header_parse() needs to parse the tunnel's ip header and it
uses mac_header to locate the iphdr. This got broken when gre tunneling
was refactored as mac_header is no longer updated to point to iphdr.
Introduce skb_pop_mac_header() helper to do the mac_header assignment
and use it in ipgre_rcv() to fix msg_name parsing.

Bug introduced in commit c54419321455 (GRE: Refactor GRE tunneling code.)

Cc: Pravin B Shelar <pshelar@...ira.com>
Signed-off-by: Timo Teräs <timo.teras@....fi>
---
Updated as suggested. Please queue for -stable too.

 include/linux/skbuff.h | 5 +++++
 net/ipv4/ip_gre.c      | 1 +
 2 files changed, 6 insertions(+)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 77c7aae..8b38a2f 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1638,6 +1638,11 @@ static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
 	skb->mac_header += offset;
 }
 
+static inline void skb_pop_mac_header(struct sk_buff *skb)
+{
+	skb->mac_header = skb->network_header;
+}
+
 static inline void skb_probe_transport_header(struct sk_buff *skb,
 					      const int offset_hint)
 {
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index d7aea4c..e560ef3 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -217,6 +217,7 @@ static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
 				  iph->saddr, iph->daddr, tpi->key);
 
 	if (tunnel) {
+		skb_pop_mac_header(skb);
 		ip_tunnel_rcv(tunnel, skb, tpi, log_ecn_error);
 		return PACKET_RCVD;
 	}
-- 
1.8.5.1

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html