From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: WARNING: at net/core/skbuff.c:154 with tcpdump and ipsec Date: Fri, 13 Feb 2009 12:14:24 +0000 Message-ID: <20090213121424.GA8717@ff.dom.local> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Marco Berizzi , netdev@vger.kernel.org To: Krzysztof Oledzki Return-path: Received: from mail-bw0-f161.google.com ([209.85.218.161]:51918 "EHLO mail-bw0-f161.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750797AbZBMMOc (ORCPT ); Fri, 13 Feb 2009 07:14:32 -0500 Received: by bwz5 with SMTP id 5so1679532bwz.13 for ; Fri, 13 Feb 2009 04:14:29 -0800 (PST) Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 11-02-2009 16:55, Krzysztof Oledzki wrote: > > On Wed, 11 Feb 2009, Marco Berizzi wrote: > >> Hi Folks, >> >> I'm getting this error on 2.6.28.4 when I run tcpdump on >> the interface where ipsec packets are enc/decrypted. >> >> TIA >> >>> Feb 11 10:53:55 Pleiadi kernel: ------------[ cut here ]------------ >>> Feb 11 10:53:55 Pleiadi kernel: WARNING: at net/core/skbuff.c:154 skb_truesize_bug+0x2e/0x33() >>> Feb 11 10:53:55 Pleiadi kernel: SKB BUG: Invalid truesize (268) len=134, sizeof(sk_buff)=172 > > > This annoying problem is quite old (appeared in 2.6.25) and already known: > http://bugzilla.kernel.org/show_bug.cgi?id=10996 > > Sadly, no one is interested in fixing it. :( Here is a debugging patch doing these checks a bit earlier, so maybe we get something new and interesting. ;) Thanks, Jarek P. --- include/linux/skbuff.h | 8 ++++++-- net/packet/af_packet.c | 9 +++++++++ 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index cf2cb50..20c3182 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -418,12 +418,16 @@ extern void skb_under_panic(struct sk_buff *skb, int len, void *here); extern void skb_truesize_bug(struct sk_buff *skb); -static inline void skb_truesize_check(struct sk_buff *skb) +static inline int skb_truesize_check(struct sk_buff *skb) { int len = sizeof(struct sk_buff) + skb->len; - if (unlikely((int)skb->truesize < len)) + if (unlikely((int)skb->truesize < len)) { skb_truesize_bug(skb); + return 1; + } + + return 0; } extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 1fc4a78..08200be 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -307,6 +307,9 @@ static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, struct if (dev_net(dev) != sock_net(sk)) goto out; + if (skb_truesize_check(skb)) + goto out; + if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) goto oom; @@ -495,6 +498,9 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet if (dev_net(dev) != sock_net(sk)) goto drop; + if (skb_truesize_check(skb)) + goto drop; + skb->dev = dev; if (dev->header_ops) { @@ -617,6 +623,9 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe if (dev_net(dev) != sock_net(sk)) goto drop; + if (skb_truesize_check(skb)) + goto drop; + if (dev->header_ops) { if (sk->sk_type != SOCK_DGRAM) skb_push(skb, skb->data - skb_mac_header(skb));