Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753154AbdLSQFE (ORCPT ); Tue, 19 Dec 2017 11:05:04 -0500 Received: from shards.monkeyblade.net ([184.105.139.130]:52414 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752695AbdLSQFB (ORCPT ); Tue, 19 Dec 2017 11:05:01 -0500 Date: Tue, 19 Dec 2017 11:04:58 -0500 (EST) Message-Id: <20171219.110458.1026495632388180098.davem@davemloft.net> To: arvind.yadav.cs@gmail.com Cc: isdn@linux-pingi.de, stephen@networkplumber.org, johannes.berg@intel.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH] isdn: avm: Handle return value of skb_dequeue() From: David Miller In-Reply-To: <5818ec104ed4354db3625ac8c7741d771719e4d4.1513453258.git.arvind.yadav.cs@gmail.com> References: <5818ec104ed4354db3625ac8c7741d771719e4d4.1513453258.git.arvind.yadav.cs@gmail.com> X-Mailer: Mew version 6.7 on Emacs 25.3 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 19 Dec 2017 08:05:00 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 456 Lines: 19 From: Arvind Yadav Date: Sun, 17 Dec 2017 01:17:23 +0530 > skb_dequeue() will return NULL for an empty list or a pointer > to the head element. > > Signed-off-by: Arvind Yadav There is no code path where this is possible. The two call sites: 1) Explicitly add an SKB to the queue OR 2) Explcitily guard the call with an skb_queue_empty() check Therefore the stated condition is not possible.