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=-9.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 22EA3C04EBD for ; Tue, 16 Oct 2018 04:13:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D64F020869 for ; Tue, 16 Oct 2018 04:13:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="tOVP4yIk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D64F020869 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728523AbeJPMBn (ORCPT ); Tue, 16 Oct 2018 08:01:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:48948 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728476AbeJPMBl (ORCPT ); Tue, 16 Oct 2018 08:01:41 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 902C121486; Tue, 16 Oct 2018 04:13:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539663199; bh=QeMX3OJ58npZBni8Er0V1zM0cg/WOodn4QkuJ5oTh0s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tOVP4yIkgF6FXF8aXU8yQMjpNSSB5sc1pbU+kjsNiDrWDDOnC9gXgc7/XmBkAapHL LHjDYFFa+Ljldm6YWKxQmmpznwXXhEyM2EtUi5cYLoYk/syB0A8myjKSrxUg3qhJ2u HEgvT4ShFMFoapZ/N7/vzE2WlQtwpjURi4Zja7V8= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Eric Dumazet , "David S . Miller" , Sasha Levin Subject: [PATCH AUTOSEL 4.18 063/100] tun: initialize napi_mutex unconditionally Date: Tue, 16 Oct 2018 00:11:44 -0400 Message-Id: <20181016041221.135528-63-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181016041221.135528-1-sashal@kernel.org> References: <20181016041221.135528-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet [ Upstream commit c7256f579f8302ce2c038181c30060d0b40017b2 ] This is the first part to fix following syzbot report : console output: https://syzkaller.appspot.com/x/log.txt?x=145378e6400000 kernel config: https://syzkaller.appspot.com/x/.config?x=443816db871edd66 dashboard link: https://syzkaller.appspot.com/bug?extid=e662df0ac1d753b57e80 Following patch is fixing the race condition, but it seems safer to initialize this mutex at tfile creation anyway. Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") Signed-off-by: Eric Dumazet Reported-by: syzbot+e662df0ac1d753b57e80@syzkaller.appspotmail.com Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/tun.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index dc2fcddb625d..410c03564a69 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -319,7 +319,6 @@ static void tun_napi_init(struct tun_struct *tun, struct tun_file *tfile, netif_napi_add(tun->dev, &tfile->napi, tun_napi_poll, NAPI_POLL_WEIGHT); napi_enable(&tfile->napi); - mutex_init(&tfile->napi_mutex); } } @@ -3241,6 +3240,7 @@ static int tun_chr_open(struct inode *inode, struct file * file) return -ENOMEM; } + mutex_init(&tfile->napi_mutex); RCU_INIT_POINTER(tfile->tun, NULL); tfile->flags = 0; tfile->ifindex = 0; -- 2.17.1