From patchwork Thu Apr 20 23:59:20 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Myungho Jung X-Patchwork-Id: 753045 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3w8G7S6WFLz9s78 for ; Fri, 21 Apr 2017 09:59:32 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="LiQPVz4E"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S948109AbdDTX7X (ORCPT ); Thu, 20 Apr 2017 19:59:23 -0400 Received: from mail-io0-f195.google.com ([209.85.223.195]:33514 "EHLO mail-io0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S947407AbdDTX7W (ORCPT ); Thu, 20 Apr 2017 19:59:22 -0400 Received: by mail-io0-f195.google.com with SMTP id k87so22449644ioi.0 for ; Thu, 20 Apr 2017 16:59:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=uzEWM9eTBjG9x6BhZCmUhB5YqJ8z9Hkh6ge5M2qcXOY=; b=LiQPVz4EIU9E3/nwJa4SvvD2a3dHc3Jqhz6QIl8LRnXRUA5xZ+xX7xdJVEmpdNy9yN uagMLS6+alW2UxNFt32ZD2LGjfDEOrPcC2poN9NY/wmVAy3Yh3lgkrFdd3/3/E4fvx0d B8ci8zRG68KL0/ZYu7BBILASMz0WRMD7ZuL0hd+nifEZZxWm5M4WpYDVth/hnRO1l00s chfAfiqMqM8jtZuSEdZDGKFR+uT2U5yEdTRw16saukPJA5Dl3aiIqRWxmyAI/61CoG9T /KXibVRMBWOYt5ZalLJl7p/DPr16gsM6ACJaHjuePTol/JULynWi2Okvr1MSCqBX13Cv 1khQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=uzEWM9eTBjG9x6BhZCmUhB5YqJ8z9Hkh6ge5M2qcXOY=; b=GB142oumkJyB9iM/M1+kiwbnaxAyr4o1SvWmN9zIuFuXm7AEoUMTyJdgd+7OpRDsmh lcY7zv7upsEbzNVt7MvrZ68ez8LGrkpQ6CGblZvhLo+/+Um7/qP5U/buAd4TsMGxiq1H XpCz1sJGXtmgFzI8MD3lfc7Zgc7/95LZRia4OAcBZy6t4MF2Pm1taRQcNe/WNEiJDemS fgQZs9FtVTtZLKzqjJ/W2t/mD2sxMAZ3rBCr6GWbvQL6LCqMJDSUNUNzS61fwJF+etwr Eo7+fjYMeWHMF4RE9AWDq6LuWY3mprO1SurAkMyDWG8b1QXc4/5vdgvpVtNyazrYImcT Tecw== X-Gm-Message-State: AN3rC/6XyuU3r9mqPPHl9KBd2qBElrUPj1V6frWnwOV1vLrUbSyfdOQ6 SdRxONXvrO+DVC7L X-Received: by 10.99.159.1 with SMTP id g1mr9669958pge.116.1492732761779; Thu, 20 Apr 2017 16:59:21 -0700 (PDT) Received: from localhost (pat_11.qualcomm.com. [192.35.156.11]) by smtp.gmail.com with ESMTPSA id p16sm12414274pgc.4.2017.04.20.16.59.20 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Apr 2017 16:59:21 -0700 (PDT) From: Myungho Jung To: edumazet@google.com Cc: netdev@vger.kernel.org Subject: [PATCH v2] net: core: Prevent from dereferencing null pointer when Date: Thu, 20 Apr 2017 16:59:20 -0700 Message-Id: <1492732760-25081-1-git-send-email-mhjungk@gmail.com> X-Mailer: git-send-email 2.7.4 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Added NULL check to make __dev_kfree_skb_irq consistent with kfree family of functions. Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289 Signed-off-by: Myungho Jung --- Changes in v2: - Correct category in subject net/core/dev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/core/dev.c b/net/core/dev.c index 7869ae3..22be2a6 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2450,6 +2450,9 @@ void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason) { unsigned long flags; + if (unlikely(!skb)) + return; + if (likely(atomic_read(&skb->users) == 1)) { smp_rmb(); atomic_set(&skb->users, 0);