From patchwork Fri Jul 9 09:04:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasily Averin X-Patchwork-Id: 472223 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9253EC07E99 for ; Fri, 9 Jul 2021 09:04:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F9DE61208 for ; Fri, 9 Jul 2021 09:04:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231781AbhGIJHb (ORCPT ); Fri, 9 Jul 2021 05:07:31 -0400 Received: from relay.sw.ru ([185.231.240.75]:59402 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229563AbhGIJHa (ORCPT ); Fri, 9 Jul 2021 05:07:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=virtuozzo.com; s=relay; h=Content-Type:MIME-Version:Date:Message-ID:Subject :From; bh=VYzyPchZWgfbWBDwBp5XfA7XY/tCeN2GdqrZ3vN/fkU=; b=NokqTyOv8BJF7MCxRZM WWWG4aKrxxatkBxrhG/BwUML/TZQ5L7ttoancHznEIO7wLfeHKf3cC7WKgDy8uaNknTatNhZsyb8V SwVnvjPdABVZwuf8sOTJzYaJdMOsdUMsgsUZXxzW4l6NPGGBgLBKHBXYuZrEdYqnMjzs4FYRjkY=; Received: from [10.93.0.56] by relay.sw.ru with esmtp (Exim 4.94.2) (envelope-from ) id 1m1mRB-003Pkm-Ku; Fri, 09 Jul 2021 12:04:45 +0300 From: Vasily Averin Subject: [PATCH IPV6 v2 1/4] ipv6: allocate enough headroom in ip6_finish_output2() To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Eric Dumazet Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1cbf3c7b-455e-f3a5-cc2c-c18ce8be4ce1@gmail.com> Message-ID: <4f6a2b28-a137-2e19-bf62-5a8767d0d0ac@virtuozzo.com> Date: Fri, 9 Jul 2021 12:04:45 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org When TEE target mirrors traffic to another interface, sk_buff may not have enough headroom to be processed correctly. ip_finish_output2() detect this situation for ipv4 and allocates new skb with enogh headroom. However ipv6 lacks this logic in ip_finish_output2 and it leads to skb_under_panic: skbuff: skb_under_panic: text:ffffffffc0866ad4 len:96 put:24 head:ffff97be85e31800 data:ffff97be85e317f8 tail:0x58 end:0xc0 dev:gre0 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:110! invalid opcode: 0000 [#1] SMP PTI CPU: 2 PID: 393 Comm: kworker/2:2 Tainted: G OE 5.13.0 #13 Hardware name: Virtuozzo KVM, BIOS 1.11.0-2.vz7.4 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:skb_panic+0x48/0x4a Call Trace: skb_push.cold.111+0x10/0x10 ipgre_header+0x24/0xf0 [ip_gre] neigh_connected_output+0xae/0xf0 ip6_finish_output2+0x1a8/0x5a0 ip6_output+0x5c/0x110 nf_dup_ipv6+0x158/0x1000 [nf_dup_ipv6] tee_tg6+0x2e/0x40 [xt_TEE] ip6t_do_table+0x294/0x470 [ip6_tables] nf_hook_slow+0x44/0xc0 nf_hook.constprop.34+0x72/0xe0 ndisc_send_skb+0x20d/0x2e0 ndisc_send_ns+0xd1/0x210 addrconf_dad_work+0x3c8/0x540 process_one_work+0x1d1/0x370 worker_thread+0x30/0x390 kthread+0x116/0x130 ret_from_fork+0x22/0x30 This patch implement new helper that tries to expand headroom on current skb, if it is not possible (shared_skb) -- creates new one. v2 open questions: - currently helper name skb_expand_head is bad and should be changed to better one. Any suggestions? - proper location for new helper: in net/core/skbuff.c right below skb_realloc_headroom() ? - is it acceptable to free original skb inside helper ? Is it probably required to keep it in caller instead? Signed-off-by: Vasily Averin --- net/ipv6/ip6_output.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index ff4f9eb..6c5f85f 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -56,14 +56,48 @@ #include #include +static inline struct sk_buff *skb_expand_head(struct sk_buff *skb, int delta) +{ + /* pskb_expand_head() might crash, if skb is shared */ + if (skb_shared(skb)) { + struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); + + if (likely(nskb)) { + if (skb->sk) + skb_set_owner_w(skb, skb->sk); + consume_skb(skb); + } else { + kfree_skb(skb); + } + skb = nskb; + } + if (skb && + pskb_expand_head(skb, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) { + kfree_skb(skb); + skb = NULL; + } + return skb; +} + static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct net_device *dev = dst->dev; + unsigned int hh_len = LL_RESERVED_SPACE(dev); + int delta = hh_len - skb_headroom(skb); const struct in6_addr *nexthop; struct neighbour *neigh; int ret; + /* Be paranoid, rather than too clever. */ + if (unlikely(delta > 0) && dev->header_ops) + skb = skb_expand_head(skb, delta); + + if (!skb) { + IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); + return -ENOMEM; + } + if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) { struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); From patchwork Fri Jul 9 09:04:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasily Averin X-Patchwork-Id: 472649 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F5E9C07E99 for ; Fri, 9 Jul 2021 09:04:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31E8F613D6 for ; Fri, 9 Jul 2021 09:04:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231815AbhGIJHk (ORCPT ); Fri, 9 Jul 2021 05:07:40 -0400 Received: from relay.sw.ru ([185.231.240.75]:59432 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229563AbhGIJHj (ORCPT ); Fri, 9 Jul 2021 05:07:39 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=virtuozzo.com; s=relay; h=Content-Type:MIME-Version:Date:Message-ID:Subject :From; bh=vxFf38SOUahWQtSH3d9qMh/k+xeLcgZ7RGmybH79yIc=; b=mngrbbURItm3FXQH2kV C6sMNJ8ZKZ1Rcgn8AwClMOawXSDMYnkMUSLKug5oyv6PWiiRtWG406V84IMUjprOK1XAeuR6ChICW E5Kj0MwqbfClATHWP49vcn14KxG0lcFqlzQKRzakHJYCRsCtqQVEYmKkuixY+AAvFyak9uAU/Is=; Received: from [10.93.0.56] by relay.sw.ru with esmtp (Exim 4.94.2) (envelope-from ) id 1m1mRK-003Pl0-TM; Fri, 09 Jul 2021 12:04:54 +0300 From: Vasily Averin Subject: [PATCH IPV6 v2 2/4] ipv6: use new helper skb_expand_head() in ip6_xmit() To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Eric Dumazet Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1cbf3c7b-455e-f3a5-cc2c-c18ce8be4ce1@gmail.com> Message-ID: <64dd5cd2-cfd9-60b3-ae1c-39470ff75256@virtuozzo.com> Date: Fri, 9 Jul 2021 12:04:54 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org By this way can be changed: pptp_xmit vrf_finish_output ax25_transmit_buffer ax25_rt_build_path bpf_out_neigh_v6 bpf_out_neigh_v4 ip_finish_output2 ip6_tnl_xmit ipip6_tunnel_xmit ip_vs_prepare_tunneled_skb Signed-off-by: Vasily Averin --- net/ipv6/ip6_output.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 6c5f85f..9418802 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -278,25 +278,21 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, struct ipv6hdr *hdr; u8 proto = fl6->flowi6_proto; int seg_len = skb->len; - int hlimit = -1; + int delta, hlimit = -1; u32 mtu; head_room = sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); if (opt) head_room += opt->opt_nflen + opt->opt_flen; - if (unlikely(skb_headroom(skb) < head_room)) { - struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); - if (!skb2) { - IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), + delta = head_room - skb_headroom(skb); + if (unlikely(delta > 0)) { + skb = skb_expand_head(skb, delta); + if (!skb) { + IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); - kfree_skb(skb); return -ENOBUFS; } - if (skb->sk) - skb_set_owner_w(skb2, skb->sk); - consume_skb(skb); - skb = skb2; } if (opt) { From patchwork Fri Jul 9 09:05:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasily Averin X-Patchwork-Id: 472222 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6F12C07E99 for ; Fri, 9 Jul 2021 09:05:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C447E613E1 for ; Fri, 9 Jul 2021 09:05:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231828AbhGIJIV (ORCPT ); Fri, 9 Jul 2021 05:08:21 -0400 Received: from relay.sw.ru ([185.231.240.75]:59556 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229563AbhGIJIV (ORCPT ); Fri, 9 Jul 2021 05:08:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=virtuozzo.com; s=relay; h=Content-Type:MIME-Version:Date:Message-ID:Subject :From; bh=bAHAmll9iZ3ZS6kuA6smeZGKYExMEehIWaRaiXEaIhw=; b=Wt+jQ05O4i1YgH8tq47 jR/tZ8+vDs94qehwiYsdfna4sIytgKqNPF04W6ccNARfk9aBKcvkI2dlAVbXGfxzQND1PCyNd1kcx G0FR91jfMWKTEXtK4WHNPL0fnKlaOEr0K3Nw4cQQQtITeaSH+HqbybfeXRIOApyU7Mj4qJwagL0=; Received: from [10.93.0.56] by relay.sw.ru with esmtp (Exim 4.94.2) (envelope-from ) id 1m1mS0-003Pln-Ik; Fri, 09 Jul 2021 12:05:36 +0300 From: Vasily Averin Subject: [PATCH IPV6 v2 3/4] ipv6: ip6_finish_output2 refactoring To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Eric Dumazet Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1cbf3c7b-455e-f3a5-cc2c-c18ce8be4ce1@gmail.com> Message-ID: Date: Fri, 9 Jul 2021 12:05:35 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Commonly used dereferences was replaced by variables. Signed-off-by: Vasily Averin --- net/ipv6/ip6_output.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 9418802..9ae3baa 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -83,9 +83,11 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * { struct dst_entry *dst = skb_dst(skb); struct net_device *dev = dst->dev; + struct inet6_dev *idev = ip6_dst_idev(dst); unsigned int hh_len = LL_RESERVED_SPACE(dev); int delta = hh_len - skb_headroom(skb); - const struct in6_addr *nexthop; + const struct in6_addr *daddr, *nexthop; + struct ipv6hdr *hdr; struct neighbour *neigh; int ret; @@ -94,18 +96,17 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * skb = skb_expand_head(skb, delta); if (!skb) { - IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS); return -ENOMEM; } - if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) { - struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb)); - + hdr = ipv6_hdr(skb); + daddr = &hdr->daddr; + if (ipv6_addr_is_multicast(daddr)) { if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) && ((mroute6_is_socket(net, skb) && !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) || - ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr, - &ipv6_hdr(skb)->saddr))) { + ipv6_chk_mcast_addr(dev, daddr, &hdr->saddr))) { struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); /* Do not check for IFF_ALLMULTI; multicast routing @@ -116,7 +117,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * net, sk, newskb, NULL, newskb->dev, dev_loopback_xmit); - if (ipv6_hdr(skb)->hop_limit == 0) { + if (hdr->hop_limit == 0) { IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS); kfree_skb(skb); @@ -125,9 +126,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * } IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, skb->len); - - if (IPV6_ADDR_MC_SCOPE(&ipv6_hdr(skb)->daddr) <= - IPV6_ADDR_SCOPE_NODELOCAL && + if (IPV6_ADDR_MC_SCOPE(daddr) <= IPV6_ADDR_SCOPE_NODELOCAL && !(dev->flags & IFF_LOOPBACK)) { kfree_skb(skb); return 0; @@ -142,10 +141,10 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * } rcu_read_lock_bh(); - nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr); - neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop); + nexthop = rt6_nexthop((struct rt6_info *)dst, daddr); + neigh = __ipv6_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) - neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false); + neigh = __neigh_create(&nd_tbl, nexthop, dev, false); if (!IS_ERR(neigh)) { sock_confirm_neigh(skb, neigh); ret = neigh_output(neigh, skb, false); @@ -154,7 +153,7 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff * } rcu_read_unlock_bh(); - IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTNOROUTES); kfree_skb(skb); return -EINVAL; } From patchwork Fri Jul 9 09:05:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasily Averin X-Patchwork-Id: 472648 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22876C07E99 for ; Fri, 9 Jul 2021 09:06:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EF7A2613E3 for ; Fri, 9 Jul 2021 09:05:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231856AbhGIJIl (ORCPT ); Fri, 9 Jul 2021 05:08:41 -0400 Received: from relay.sw.ru ([185.231.240.75]:59616 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229563AbhGIJIl (ORCPT ); Fri, 9 Jul 2021 05:08:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=virtuozzo.com; s=relay; h=Content-Type:MIME-Version:Date:Message-ID:Subject :From; bh=5IC5mFOPOS1MYS+1HKMaliBZpQ6ReLTErUGh1yA0hKY=; b=roQp0qK+YgXRwKYEp+z l7PwAFEYtz3WeqRY/IrJU9/diaoq1Zk1Q/Lr6u65L9ig0A6WNH9Cy7ph0BILAb32936Q1aTxNpKWS ntd4oP1wwx+DzQKy3pMA1EbRCU2wyY4hLLvY8nOp47BL1d7goP+cprx+hFxEmevg9pTf02a+Q0o=; Received: from [10.93.0.56] by relay.sw.ru with esmtp (Exim 4.94.2) (envelope-from ) id 1m1mSK-003Pm1-Qs; Fri, 09 Jul 2021 12:05:56 +0300 From: Vasily Averin Subject: [PATCH IPV6 v2 4/4] ipv6: ip6_xmit refactoring To: "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Eric Dumazet Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1cbf3c7b-455e-f3a5-cc2c-c18ce8be4ce1@gmail.com> Message-ID: Date: Fri, 9 Jul 2021 12:05:56 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Commonly used dereferences was replaced by variables. Signed-off-by: Vasily Averin --- net/ipv6/ip6_output.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 9ae3baa..5e33429 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -273,6 +273,8 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, const struct ipv6_pinfo *np = inet6_sk(sk); struct in6_addr *first_hop = &fl6->daddr; struct dst_entry *dst = skb_dst(skb); + struct net_device *dev = dst->dev; + struct inet6_dev *idev = ip6_dst_idev(dst); unsigned int head_room; struct ipv6hdr *hdr; u8 proto = fl6->flowi6_proto; @@ -280,7 +282,7 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, int delta, hlimit = -1; u32 mtu; - head_room = sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); + head_room = sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dev); if (opt) head_room += opt->opt_nflen + opt->opt_flen; @@ -288,8 +290,7 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, if (unlikely(delta > 0)) { skb = skb_expand_head(skb, delta); if (!skb) { - IP6_INC_STATS(net, ip6_dst_idev(dst), - IPSTATS_MIB_OUTDISCARDS); + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS); return -ENOBUFS; } } @@ -333,8 +334,7 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, mtu = dst_mtu(dst); if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) { - IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)), - IPSTATS_MIB_OUT, skb->len); + IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); /* if egress device is enslaved to an L3 master device pass the * skb to its handler for processing @@ -347,17 +347,17 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, * we promote our socket to non const */ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, - net, (struct sock *)sk, skb, NULL, dst->dev, + net, (struct sock *)sk, skb, NULL, dev, dst_output); } - skb->dev = dst->dev; + skb->dev = dev; /* ipv6_local_error() does not require socket lock, * we promote our socket to non const */ ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu); - IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS); + IP6_INC_STATS(net, idev, IPSTATS_MIB_FRAGFAILS); kfree_skb(skb); return -EMSGSIZE; }