From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Hartkopp Subject: Re: [PATCH] 3c507.c: remove unused NULL pointer check Date: Mon, 21 Dec 2009 17:56:39 +0100 Message-ID: <4B2FA8C7.3010509@hartkopp.net> References: <200912211923.58735.strakh@ispras.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: Bartlomiej Zolnierkiewicz , Donald Becker , netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Alexander Strakh Return-path: Received: from mo-p00-ob.rzone.de ([81.169.146.161]:32026 "EHLO mo-p00-ob.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754825AbZLUQ4n (ORCPT ); Mon, 21 Dec 2009 11:56:43 -0500 In-Reply-To: <200912211923.58735.strakh@ispras.ru> Sender: netdev-owner@vger.kernel.org List-ID: Alexander Strakh wrote: > In driver drivers/net/3c507.c in function Iirqreturn_t el16_interrupt: > 1. If in line 555 dev = NULL then we goto line 556 > 2. In line 556 we have null dereference because pr_err called with dev->name > in third parameter. > 555 if (dev == NULL) { > 556 pr_err("%s: net_interrupt(): irq %d for unknown device. > \n", > 557 dev->name, irq); > 558 return IRQ_NONE; > 559 } > > Found by Linux Device Drivers Verification (Svace detector) > > Remove unused NULL pointer check. You are obviously doing more than that ... > > Signed-off-by: Alexander Strakh > > --- > diff --git a/./0000/drivers/net/3c507.c b/./moder/drivers/net/3c507.c > index fbc2311..3bfb3dd 100644 > --- a/./0000/drivers/net/3c507.c > +++ b/./moder/drivers/net/3c507.c > @@ -552,12 +552,6 @@ static irqreturn_t el16_interrupt(int irq, void *dev_id) > ushort ack_cmd = 0; > void __iomem *shmem; > > - if (dev == NULL) { > - pr_err("%s: net_interrupt(): irq %d for unknown device.\n", > - dev->name, irq); You are changing real funcionality here! If you want to fix it, fix the pr_err() but do not remove the "return IRQ_NONE" entirely. This looks like an introduction of a bug. Regards, Oliver > - return IRQ_NONE; > - } > -