From mboxrd@z Thu Jan 1 00:00:00 1970 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 08BB0C3A5A1 for ; Thu, 22 Aug 2019 17:11:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6E0623405 for ; Thu, 22 Aug 2019 17:11:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566493878; bh=ag69XH0HK/mqy35v/SJsvTO77r9YWwBqbkrfQzcvab4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ToFyU6oOUdK3KnBDyic6mnets94OGPEoLxLQs28nICvcS1EIt0/Yb9KnagH2dHNFK Kmdn4CBubymeLKuMkJLM1upJT3Qrxeegl40T/j5VM62lTxWiX1n5Aai2pzOPrDd/9k b+L5SHzMumaecDh2+AvD/dZELZP8x2uySvo3TVl8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390874AbfHVRLD (ORCPT ); Thu, 22 Aug 2019 13:11:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:59656 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390723AbfHVRJS (ORCPT ); Thu, 22 Aug 2019 13:09:18 -0400 Received: from sasha-vm.mshome.net (wsip-184-188-36-2.sd.sd.cox.net [184.188.36.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 740DE2342B; Thu, 22 Aug 2019 17:09:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566493757; bh=ag69XH0HK/mqy35v/SJsvTO77r9YWwBqbkrfQzcvab4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mdeHmwPkTYJKek4WVF05jdvm9TSfJCqPCkHEC2X9kv4HbjxIApAxCKgc6bJZ6X5Tn Yu87OVFITmzlIFq/igrwhtMdTv/TX5Ww5+8pIAqCCDGDHsxMXQSrNlgXulV3xWFIL5 vgbW1CzWRuRhTciF+NtEDg3iZNJGMufy1G2ywLQY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ross Lagerwall , "David S . Miller" , Greg Kroah-Hartman Subject: [PATCH 5.2 117/135] xen/netback: Reset nr_frags before freeing skb Date: Thu, 22 Aug 2019 13:07:53 -0400 Message-Id: <20190822170811.13303-118-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190822170811.13303-1-sashal@kernel.org> References: <20190822170811.13303-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.2.10-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.2.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.2.10-rc1 X-KernelTest-Deadline: 2019-08-24T17:07+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ross Lagerwall [ Upstream commit 3a0233ddec554b886298de2428edb5c50a20e694 ] At this point nr_frags has been incremented but the frag does not yet have a page assigned so freeing the skb results in a crash. Reset nr_frags before freeing the skb to prevent this. Signed-off-by: Ross Lagerwall Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/xen-netback/netback.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 1d9940d4e8c7d..c9262ffeefe4c 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -925,6 +925,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue, skb_shinfo(skb)->nr_frags = MAX_SKB_FRAGS; nskb = xenvif_alloc_skb(0); if (unlikely(nskb == NULL)) { + skb_shinfo(skb)->nr_frags = 0; kfree_skb(skb); xenvif_tx_err(queue, &txreq, extra_count, idx); if (net_ratelimit()) @@ -940,6 +941,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue, if (xenvif_set_skb_gso(queue->vif, skb, gso)) { /* Failure in xenvif_set_skb_gso is fatal. */ + skb_shinfo(skb)->nr_frags = 0; kfree_skb(skb); kfree_skb(nskb); break; -- 2.20.1