From patchwork Thu Jun 2 16:18:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 12867984 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EF273C43334 for ; Thu, 2 Jun 2022 16:19:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236921AbiFBQTH (ORCPT ); Thu, 2 Jun 2022 12:19:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57180 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236857AbiFBQTG (ORCPT ); Thu, 2 Jun 2022 12:19:06 -0400 Received: from mail-pl1-x632.google.com (mail-pl1-x632.google.com [IPv6:2607:f8b0:4864:20::632]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7547466AE2 for ; Thu, 2 Jun 2022 09:19:05 -0700 (PDT) Received: by mail-pl1-x632.google.com with SMTP id o17so4907725pla.6 for ; Thu, 02 Jun 2022 09:19:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=v7haQdok9coGoBH/EHypawu9uqZLEMnEJgP66s9Q60I=; b=CQK+hsqS4vLpYpgAptw5ioqzbrtyt8l5SOIQYZJBdFLvCgd4I/JVHBa3y29wvwRLxW B805u0CyEWeLuI9uIu3vH1PI468ElW5EX2sttHDZVM/uOm+dhoCHuuleFIJbFlvK1Mpu xohU40qoWmlQvC30QJYg3awDYU6lu7nFXCLwq+RBUkiWP5Ags1TM9wVGeVKm0XzgU4F1 M+ZLq2jgKupgFgQyY5nJS2WsLR7/a1Pg1/xsElgb7aQqH2iKbEjK5vDgSxa1qLaibViw BTP7ODfbcYb/tr3zCMjyaGp5uWEjF4h30u9isPsApYOrgAwuyfT+jPS0SYXMKtcE+vfP YcPQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=v7haQdok9coGoBH/EHypawu9uqZLEMnEJgP66s9Q60I=; b=RbyKM7T3MOgDV7N7qn8vr1lKAz0/ZwjTVmwDk2tPc61FSBDyvV4xakegtXKt8/a6+H Cz9t3tRrquvLxW/pCcGwZ+p5+yeCe86kNb69d40VvO4kq0Sk3rYKUoF2DRYqbONZTirL hkaWR9ok1SWFxxdADcm1CrManMlYCGA8H2oYsf7iAzsLD4Lr2NoYdZucVmofMpUDmA9e Bym3mIoxVWDDTOtWMjmKpxuVp7eZadux4Q+Urr8HkQNiG7T3+iuz0umezkyEbclBmPkC lWot5tshaadRhPRiqBlJjK6Sjkd2AVoU6MClyryVXeZfOk5nA0kM+Yk92fGpt2lDmoQW NIiA== X-Gm-Message-State: AOAM532YVhF1ykrUgKbse0HgVIWtSvevAlDJUy0d5MDP2lSnHLgsoL3O QUEY5ZAfqsjbDh6IWhV9+6g= X-Google-Smtp-Source: ABdhPJxJY3cwNwAD39WreA6COGbrBESyxLkjp6O864VSUtjcboU87avq5sIjNW47HwlENyIOsP79qg== X-Received: by 2002:a17:90b:4a8c:b0:1e2:f378:631d with SMTP id lp12-20020a17090b4a8c00b001e2f378631dmr6058116pjb.58.1654186745035; Thu, 02 Jun 2022 09:19:05 -0700 (PDT) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:1ff3:6bf6:224:48f2]) by smtp.gmail.com with ESMTPSA id u25-20020a62ed19000000b00518895f0dabsm3751072pfh.59.2022.06.02.09.19.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Jun 2022 09:19:04 -0700 (PDT) From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev , Willem de Bruijn , Eric Dumazet , Eric Dumazet Subject: [PATCH v2 net 1/3] net: CONFIG_DEBUG_NET depends on CONFIG_NET Date: Thu, 2 Jun 2022 09:18:57 -0700 Message-Id: <20220602161859.2546399-2-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.36.1.255.ge46751e96f-goog In-Reply-To: <20220602161859.2546399-1-eric.dumazet@gmail.com> References: <20220602161859.2546399-1-eric.dumazet@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Eric Dumazet It makes little sense to debug networking stacks if networking is not compiled in. Signed-off-by: Eric Dumazet --- net/Kconfig.debug | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/Kconfig.debug b/net/Kconfig.debug index a5781cf63b16b32e5360df1ca26a753b6505d81f..e6ae11cc2fb7cb90e6a0c063d2135ee1839c3ead 100644 --- a/net/Kconfig.debug +++ b/net/Kconfig.debug @@ -20,7 +20,7 @@ config NET_NS_REFCNT_TRACKER config DEBUG_NET bool "Add generic networking debug" - depends on DEBUG_KERNEL + depends on DEBUG_KERNEL && NET help Enable extra sanity checks in networking. This is mostly used by fuzzers, but is safe to select. From patchwork Thu Jun 2 16:18:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 12867986 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C84CAC433EF for ; Thu, 2 Jun 2022 16:19:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236926AbiFBQTP (ORCPT ); Thu, 2 Jun 2022 12:19:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57770 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236929AbiFBQTL (ORCPT ); Thu, 2 Jun 2022 12:19:11 -0400 Received: from mail-pf1-x430.google.com (mail-pf1-x430.google.com [IPv6:2607:f8b0:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27A91286818 for ; Thu, 2 Jun 2022 09:19:07 -0700 (PDT) Received: by mail-pf1-x430.google.com with SMTP id bo5so5153866pfb.4 for ; Thu, 02 Jun 2022 09:19:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=lMvhSjta3uPc3bafTOd2m+dUMTCYus4sC7njlmQr8LI=; b=Ni9tcgecPjxQYf0WKWRMA0r4Aq3MiEOHhTUqLp0nfMPfm8lSyp7IgLacqHJxnMWPaS Y3gpR7wzvV7CEhMIvf6i/2peeDYj7I5Q2kURzzRs5tOPrMmCtHQ1OBVNkEEwI/+D2bpr ZpZb1PhGkQwLwkJdQSwL4uBVS3xZAUZPEpEdTiMndrN1+k4/6tyy/eta1oBkpYWT9LL6 9l5uroFj+LBT/laL6Nue9t1ClxpzPOzlZqmRFxR4UOTbqiVkZjIwLJGJkTETBR26VZmQ 4OYJdZpDS8/onD2Z8mxXx7BXrH7MZmEm4r+CQjAPCJB5qh7VfhiWwebReUwaUgOcrbK9 NYkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=lMvhSjta3uPc3bafTOd2m+dUMTCYus4sC7njlmQr8LI=; b=wnUn5JasPEsMyWzXRA+eSkqd4NkpabZg/9H0xyUZIKChFOgYksPkPEyF2QRpnDq/zr yZev5laMoxN0Yj9TMhsQdo+AFMx9UYXNyhi2H0XZe1p17cHo1BrAeBjKfz4x0copJvuV jQ0wrJIn80ylJSoPjnKEXD4xa3nvYDV/eQ4l++SDe+Ma86bgf/B2grERz3Pi9d8N93o7 1KaN5lztN/6D1/zfn1vYyKAnY29Gy/tuTMD1qVYbhD8l3JTpcNe/cGIAoLgh22UQhmTC Jak4nfo9xXI9HtcsYLDitycQwtSZQylG3y2SpSs9T1Q+Nx9OHXH3+QcpZcB+eHukceRr QlQQ== X-Gm-Message-State: AOAM531ty9ynB18LFY6xyposgO5eVQ7mZo4rZ+HbWUxIyz7Zp8PFm7HY L8oVtdyFkZFCk0/16qVtby9QigjuA4M= X-Google-Smtp-Source: ABdhPJxQo4tG2qHOOm3soNY57m6uk3ZtHdCHP9buwlLc/HRWhX3jsh219AqGs2PYJ8QqjNFMe6xlow== X-Received: by 2002:a62:7b94:0:b0:51b:c723:5724 with SMTP id w142-20020a627b94000000b0051bc7235724mr4344713pfc.8.1654186746642; Thu, 02 Jun 2022 09:19:06 -0700 (PDT) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:1ff3:6bf6:224:48f2]) by smtp.gmail.com with ESMTPSA id u25-20020a62ed19000000b00518895f0dabsm3751072pfh.59.2022.06.02.09.19.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Jun 2022 09:19:06 -0700 (PDT) From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev , Willem de Bruijn , Eric Dumazet , Eric Dumazet Subject: [PATCH v2 net 2/3] net: add debug info to __skb_pull() Date: Thu, 2 Jun 2022 09:18:58 -0700 Message-Id: <20220602161859.2546399-3-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.36.1.255.ge46751e96f-goog In-Reply-To: <20220602161859.2546399-1-eric.dumazet@gmail.com> References: <20220602161859.2546399-1-eric.dumazet@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Eric Dumazet While analyzing yet another syzbot report, I found the following patch very useful. It allows to better understand what went wrong. This debug info is only enabled if CONFIG_DEBUG_NET=y, which is the case for syzbot builds. Signed-off-by: Eric Dumazet Acked-by: Willem de Bruijn --- include/linux/skbuff.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index da96f0d3e753fb7996631bc9350c0c8e0ec5966e..d3d10556f0faea8c8c1deed5715716d4916011d1 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2696,7 +2696,14 @@ void *skb_pull(struct sk_buff *skb, unsigned int len); static inline void *__skb_pull(struct sk_buff *skb, unsigned int len) { skb->len -= len; - BUG_ON(skb->len < skb->data_len); + if (unlikely(skb->len < skb->data_len)) { +#if defined(CONFIG_DEBUG_NET) + skb->len += len; + pr_err("__skb_pull(len=%u)\n", len); + skb_dump(KERN_ERR, skb, false); +#endif + BUG(); + } return skb->data += len; } From patchwork Thu Jun 2 16:18:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 12867985 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C357CC433EF for ; Thu, 2 Jun 2022 16:19:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236857AbiFBQTO (ORCPT ); Thu, 2 Jun 2022 12:19:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236933AbiFBQTN (ORCPT ); Thu, 2 Jun 2022 12:19:13 -0400 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C49D92AD989 for ; Thu, 2 Jun 2022 09:19:08 -0700 (PDT) Received: by mail-pg1-x535.google.com with SMTP id y187so5164806pgd.3 for ; Thu, 02 Jun 2022 09:19:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=+Dk/Dt5SZeV5tf4KA0Zng3rYDhsewVJ5+4RxLwbLLAY=; b=fd6B7b6Su7gUBL8c92Y6AhGbbDVknyetkbp/psQjp5KLTubOUKeiEBgDxQ4/QptKQt nGoS2qQSqhoZetX5nFmSKUxvkbv7kz7QcSvd4ed429K0KMwcrHOzVzAEwF6mXcwO4QpR SWr8IwULm7Rn5ulJkT0K4JoEvAwvay4szkl9RZ8AJWcL9n45M7TFh3fqW8xwzR3M+tx+ nKzuSYwt39lxmvmi8Nu00dMFaqGsDMiVgUUZQUrKhW1TwtSKk96loESXz4T+kdN3zJKB gY+Sh28rM0QYvxXypD1Aa7bgbj9DfZGsWfTOclMEx2dcdiLjt8Q858yxlUJVP9wI0jqj fvvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=+Dk/Dt5SZeV5tf4KA0Zng3rYDhsewVJ5+4RxLwbLLAY=; b=hoPvQ0RXsHQ4EBH8ZGu7kWAGYEvkMFBKmqmTuJSvTeZpf7ZO/fv8YtfXEJytf0Bc9k CnF7hWzwqOJ6mY+SRDBDYWn0jCWyLHaVGrdXYQmEqKLaTP2vJtB8yNNshzbJXZ+QW0dT xF80Jl9Uj0iqLc9dwG2O+nsYh+PDvEIRKDev0xDjG7s7clSlfNcEhl8ZnOgzaofgxa6U SW9t5n8BpV8iAs2ZCveGTPX+0oB1yeBArFBmumqzm6GzvhDA1A3KT4Mlm5dVfsMosv4o Gsyoua7P5kjkO+mXgEbWJoKNvyqoCVw4BqIOUwogVFskEo0C0GeqKh+7DhP3CMzOHBRf KvDw== X-Gm-Message-State: AOAM531Y9v24p8yB0wPPRbCIR5FLWDAA+DIWv80BhvOkreYWf5PDt6NW 5IY8n/L6WQ89JEKuuWzeigQ= X-Google-Smtp-Source: ABdhPJwblayCL2HqA0ypV6hX9mzH9ntZq5KFP37TuyJnf8meQfNPF155zduslYvcpZ7gX1RPwYAzOw== X-Received: by 2002:a05:6a00:1146:b0:4c9:ede0:725a with SMTP id b6-20020a056a00114600b004c9ede0725amr5887763pfm.35.1654186748185; Thu, 02 Jun 2022 09:19:08 -0700 (PDT) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:1ff3:6bf6:224:48f2]) by smtp.gmail.com with ESMTPSA id u25-20020a62ed19000000b00518895f0dabsm3751072pfh.59.2022.06.02.09.19.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Jun 2022 09:19:07 -0700 (PDT) From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev , Willem de Bruijn , Eric Dumazet , Eric Dumazet , syzbot , Hangbin Liu , "Michael S . Tsirkin" Subject: [PATCH v2 net 3/3] net/af_packet: make sure to pull mac header Date: Thu, 2 Jun 2022 09:18:59 -0700 Message-Id: <20220602161859.2546399-4-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.36.1.255.ge46751e96f-goog In-Reply-To: <20220602161859.2546399-1-eric.dumazet@gmail.com> References: <20220602161859.2546399-1-eric.dumazet@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Eric Dumazet GSO assumes skb->head contains link layer headers. tun device in some case can provide base 14 bytes, regardless of VLAN being used or not. After blamed commit, we can end up setting a network header offset of 18+, we better pull the missing bytes to avoid a posible crash in GSO. syzbot report was: kernel BUG at include/linux/skbuff.h:2699! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 3601 Comm: syz-executor210 Not tainted 5.18.0-syzkaller-11338-g2c5ca23f7414 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__skb_pull include/linux/skbuff.h:2699 [inline] RIP: 0010:skb_mac_gso_segment+0x48f/0x530 net/core/gro.c:136 Code: 00 48 c7 c7 00 96 d4 8a c6 05 cb d3 45 06 01 e8 26 bb d0 01 e9 2f fd ff ff 49 c7 c4 ea ff ff ff e9 f1 fe ff ff e8 91 84 19 fa <0f> 0b 48 89 df e8 97 44 66 fa e9 7f fd ff ff e8 ad 44 66 fa e9 48 RSP: 0018:ffffc90002e2f4b8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000012 RCX: 0000000000000000 RDX: ffff88805bb58000 RSI: ffffffff8760ed0f RDI: 0000000000000004 RBP: 0000000000005dbc R08: 0000000000000004 R09: 0000000000000fe0 R10: 0000000000000fe4 R11: 0000000000000000 R12: 0000000000000fe0 R13: ffff88807194d780 R14: 1ffff920005c5e9b R15: 0000000000000012 FS: 000055555730f300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200015c0 CR3: 0000000071ff8000 CR4: 0000000000350ee0 Call Trace: __skb_gso_segment+0x327/0x6e0 net/core/dev.c:3411 skb_gso_segment include/linux/netdevice.h:4749 [inline] validate_xmit_skb+0x6bc/0xf10 net/core/dev.c:3669 validate_xmit_skb_list+0xbc/0x120 net/core/dev.c:3719 sch_direct_xmit+0x3d1/0xbe0 net/sched/sch_generic.c:327 __dev_xmit_skb net/core/dev.c:3815 [inline] __dev_queue_xmit+0x14a1/0x3a00 net/core/dev.c:4219 packet_snd net/packet/af_packet.c:3071 [inline] packet_sendmsg+0x21cb/0x5550 net/packet/af_packet.c:3102 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 ____sys_sendmsg+0x6eb/0x810 net/socket.c:2492 ___sys_sendmsg+0xf3/0x170 net/socket.c:2546 __sys_sendmsg net/socket.c:2575 [inline] __do_sys_sendmsg net/socket.c:2584 [inline] __se_sys_sendmsg net/socket.c:2582 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2582 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f4b95da06c9 Code: 28 c3 e8 4a 15 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd7defc4c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ffd7defc4f0 RCX: 00007f4b95da06c9 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 0000000000000003 R08: bb1414ac00000050 R09: bb1414ac00000050 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd7defc4e0 R14: 00007ffd7defc4d8 R15: 00007ffd7defc4d4 Fixes: dfed913e8b55 ("net/af_packet: add VLAN support for AF_PACKET SOCK_RAW GSO") Signed-off-by: Eric Dumazet Reported-by: syzbot Acked-by: Hangbin Liu Acked-by: Willem de Bruijn Cc: Michael S. Tsirkin Acked-by: Michael S. Tsirkin --- net/packet/af_packet.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 677f9cfa9660816a160a11bfa4c291431412005f..ca6e92a229239f9093900bf9249396cf0d410104 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1935,8 +1935,10 @@ static void packet_parse_headers(struct sk_buff *skb, struct socket *sock) /* Move network header to the right position for VLAN tagged packets */ if (likely(skb->dev->type == ARPHRD_ETHER) && eth_type_vlan(skb->protocol) && - __vlan_get_protocol(skb, skb->protocol, &depth) != 0) - skb_set_network_header(skb, depth); + __vlan_get_protocol(skb, skb->protocol, &depth) != 0) { + if (pskb_may_pull(skb, depth)) + skb_set_network_header(skb, depth); + } skb_probe_transport_header(skb); }