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=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 A8B17C433FF for ; Mon, 29 Jul 2019 07:41:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A4572064A for ; Mon, 29 Jul 2019 07:41:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=resnulli-us.20150623.gappssmtp.com header.i=@resnulli-us.20150623.gappssmtp.com header.b="U3Oyx9zN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726817AbfG2Hl2 (ORCPT ); Mon, 29 Jul 2019 03:41:28 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:44972 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726708AbfG2Hl2 (ORCPT ); Mon, 29 Jul 2019 03:41:28 -0400 Received: by mail-wr1-f67.google.com with SMTP id p17so60617760wrf.11 for ; Mon, 29 Jul 2019 00:41:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=resnulli-us.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=ORbzlsHDa5hfAtYywIFIzyHDT+ZvebWOt6YTGvwMpig=; b=U3Oyx9zN4u2Gtbuvjv+zgxcVNpE6ZKb70DCl4DIEj3I4V9ml3D84LExFTzRYkfan6s NRYpbieyI3krseoucYfTo3uWhnm/qloBGOsfAQeLeKSMTPmLVq5mhJNmvLkNWMpW3kw0 8N7dxwE0J4bRWdRsK2a/ECi91IdaNWUrY6huK4eVd0YX1WVVHXNfCjobSYS+9Q7Aaahr T2G43s/XcEQ8J+Kdb1dFGpzgHBXSXiAC8fhlwt7V+KlWya1e7Ew0hv/VYl9wPNUvz8X7 eCbL/7s2XVxgsrzOo5tkUEXOyGnO97DA9+NRaWTJKc56tnKpHdiFA0MikkGwnPtx2ZT5 nmcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=ORbzlsHDa5hfAtYywIFIzyHDT+ZvebWOt6YTGvwMpig=; b=a2DO2FhZfanphYUe4j1vC0LjO2HTSZuk9mY+BuY7awx0eqbyEQiEHeDnoBBaXCnNR2 sHSTv3axSI9lgc5dsvZ5D9bdEVDN/OpJfSMuvGJoMIGlU9uMOxkpmINv043+Lu+64oG6 1bx7THlbCSkpb75irs5YJy2mQNcx6hjQGU5zumxopO+Nbt5K4O3/coRVFDGuPeN64AzB a3WynHt97rDQl3KKwmaw4E04Tsf2/x0HLMQKPjBNeYroWALKgOFYAZdaTos02Gs8l8aC P8xiuEW3heqYGq94PPraE1nYIMr5pOX0oOS1YlwtEV54eCjHGf1eE0h+QjdT5WfI0mOg +56Q== X-Gm-Message-State: APjAAAWy5V443NlnZh9q/UtZN1xzr1ZKrulDvnqlca2FbEcmjycjubKE riM8wG6w8jPYOgESVFNJgdE= X-Google-Smtp-Source: APXvYqw+rYnER7GSElPp44lGXfPWqu3WnBnRAu+1fqDmgcedrvhr4Z2/zTlGTzHIKSvjGwIqDz7wBg== X-Received: by 2002:a5d:43c9:: with SMTP id v9mr45383532wrr.70.1564386086100; Mon, 29 Jul 2019 00:41:26 -0700 (PDT) Received: from localhost (mail.chocen-mesto.cz. [85.163.43.2]) by smtp.gmail.com with ESMTPSA id v18sm63277633wrs.80.2019.07.29.00.41.25 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Mon, 29 Jul 2019 00:41:25 -0700 (PDT) Date: Mon, 29 Jul 2019 09:41:25 +0200 From: Jiri Pirko To: Jia-Ju Bai Cc: jhs@mojatatu.com, xiyou.wangcong@gmail.com, davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: sched: Fix a possible null-pointer dereference in dequeue_func() Message-ID: <20190729074125.GB2211@nanopsycho> References: <20190729022157.18090-1-baijiaju1990@gmail.com> <20190729065653.GA2211@nanopsycho> <4752bf67-7a0c-7bc9-3d54-f18361085ba2@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4752bf67-7a0c-7bc9-3d54-f18361085ba2@gmail.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Mon, Jul 29, 2019 at 09:32:00AM CEST, baijiaju1990@gmail.com wrote: > > >On 2019/7/29 14:56, Jiri Pirko wrote: >> Mon, Jul 29, 2019 at 04:21:57AM CEST, baijiaju1990@gmail.com wrote: >> > In dequeue_func(), there is an if statement on line 74 to check whether >> > skb is NULL: >> > if (skb) >> > >> > When skb is NULL, it is used on line 77: >> > prefetch(&skb->end); >> > >> > Thus, a possible null-pointer dereference may occur. >> > >> > To fix this bug, skb->end is used when skb is not NULL. >> > >> > This bug is found by a static analysis tool STCheck written by us. >> > >> > Signed-off-by: Jia-Ju Bai >> Fixes tag, please? > >Sorry, I do not know what "fixes tag" means... >I just find a possible bug and fix it in this patch. git log |grep Fixes: If A fix goes to -net tree, it most probably fixes some bug introduced by some commit in the past. So this tag is to put a reference. > > >Best wishes, >Jia-Ju Bai