netdev - ip_gre headroom allocation

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]

Message-ID: <4A30BECA.8030205@iki.fi>
Date:	Thu, 11 Jun 2009 11:22:34 +0300
From:	Timo Teräs <timo.teras@....fi>
To:	netdev@...r.kernel.org
CC:	Herbert Xu <herbert@...dor.apana.org.au>,
	Alexey Kuznetsov <kuznet@....inr.ac.ru>,
	David Miller <davem@...emloft.net>
Subject: ip_gre headroom allocation

I'm not entirely sure about this, but shouldn't we do something like
the below to make ip_gre allocation enough headroom for paths where
e.g. xfrm transformations take place (as a speed optimization)?

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index e62510d..eb78dd9 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -812,7 +812,7 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
                        tunnel->err_count = 0;
        }
 
-       max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen;
+       max_headroom = LL_RESERVED_SPACE(tdev) + gre_hlen + rt->u.dst.header_len;
 
        if (skb_headroom(skb) < max_headroom || skb_shared(skb)||
            (skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
--
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