From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joonwoo Park Subject: Re: [PATCH] llc: fix skb size for test responses Date: Tue, 26 Feb 2008 16:00:25 +0900 Message-ID: <20080226070025.GA24954@ehus.geninetworks.com> References: <20080224190758.GW84358@surrealistic.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, acme@ghostprotocols.net, David Miller To: Jim Westfall Return-path: Received: from wf-out-1314.google.com ([209.85.200.173]:6661 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753455AbYBZHAZ (ORCPT ); Tue, 26 Feb 2008 02:00:25 -0500 Received: by wf-out-1314.google.com with SMTP id 28so1215769wff.4 for ; Mon, 25 Feb 2008 23:00:25 -0800 (PST) Content-Disposition: inline In-Reply-To: <20080224190758.GW84358@surrealistic.net> Sender: netdev-owner@vger.kernel.org List-ID: On Sun, Feb 24, 2008 at 11:07:58AM -0800, Jim Westfall wrote: > Hi > > The llc test command is used for a layer2 ping and contains a variable > length payload that we must include in the response. Use the size of the > received skb as the size of the skb we must allocate to hold the payload. > > This resolved an skb_over_panic(), when trying to copy the payload into > what was a hard coded skb of size 128. > > Signed-off-by: Jim Westfall > > diff -urp linux-2.6.24.2.org/net/llc/llc_s_ac.c linux-2.6.24.2/net/llc/llc_s_ac.c > --- linux-2.6.24.2.org/net/llc/llc_s_ac.c 2008-02-10 21:51:11.000000000 -0800 > +++ linux-2.6.24.2/net/llc/llc_s_ac.c 2008-02-24 10:15:02.000000000 -0800 > @@ -148,9 +148,18 @@ int llc_sap_action_send_test_r(struct ll > llc_pdu_decode_sa(skb, mac_da); > llc_pdu_decode_da(skb, mac_sa); > llc_pdu_decode_ssap(skb, &dsap); > - nskb = llc_alloc_frame(NULL, skb->dev); > + nskb = alloc_skb(skb->end - skb->head, GFP_ATOMIC); Jim, Not enough. Because of 'skb_reserve(nskb, 50)', we need additional 50bytes. > + > if (!nskb) > goto out; > + > + skb_reset_mac_header(nskb); > + skb_reserve(nskb, 50); > + skb_reset_network_header(nskb); > + skb_reset_transport_header(nskb); > + nskb->protocol = htons(ETH_P_802_2); > + nskb->dev = skb->dev; > + > llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap, > LLC_PDU_RSP); > llc_pdu_init_as_test_rsp(nskb, skb); > diff -urp linux-2.6.24.2.org/net/llc/llc_station.c linux-2.6.24.2/net/llc/llc_station.c > --- linux-2.6.24.2.org/net/llc/llc_station.c 2008-02-10 21:51:11.000000000 -0800 > +++ linux-2.6.24.2/net/llc/llc_station.c 2008-02-24 10:10:01.000000000 -0800 > @@ -298,10 +298,18 @@ static int llc_station_ac_send_test_r(st > { > u8 mac_da[ETH_ALEN], dsap; > int rc = 1; > - struct sk_buff *nskb = llc_alloc_frame(NULL, skb->dev); > + struct sk_buff *nskb = alloc_skb(skb->end - skb->head, GFP_ATOMIC); Also here. > > if (!nskb) > goto out; > + > + skb_reset_mac_header(nskb); > + skb_reserve(nskb, 50); > + skb_reset_network_header(nskb); > + skb_reset_transport_header(nskb); > + nskb->protocol = htons(ETH_P_802_2); > + nskb->dev = skb->dev; > + > rc = 0; > llc_pdu_decode_sa(skb, mac_da); > llc_pdu_decode_ssap(skb, &dsap); > Thanks, Joonwoo > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html