From mboxrd@z Thu Jan 1 00:00:00 1970 From: Myungho Jung Subject: Re: [PATCH v2] net: core: Prevent from dereferencing null pointer when Date: Mon, 24 Apr 2017 18:36:57 -0700 Message-ID: <20170425013657.GA11509@fqdn.specialj.com> References: <1492732760-25081-1-git-send-email-mhjungk@gmail.com> <20170424.120235.438297438450788048.davem@davemloft.net> <20170425010052.GA8717@fqdn.specialj.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Miller , netdev To: Eric Dumazet Return-path: Received: from mail-pf0-f196.google.com ([209.85.192.196]:35831 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965820AbdDYBhA (ORCPT ); Mon, 24 Apr 2017 21:37:00 -0400 Received: by mail-pf0-f196.google.com with SMTP id a188so7110246pfa.2 for ; Mon, 24 Apr 2017 18:37:00 -0700 (PDT) Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Apr 24, 2017 at 06:10:32PM -0700, Eric Dumazet wrote: > On Mon, Apr 24, 2017 at 6:00 PM, Myungho Jung wrote: > > On Mon, Apr 24, 2017 at 12:02:35PM -0400, David Miller wrote: > >> From: Myungho Jung > >> Date: Thu, 20 Apr 2017 16:59:20 -0700 > >> > >> > 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 > >> > >> This subject line is an incomplete sentence. > >> > >> This patch prevents dereferenccing a null pointer when "what"? > > > > As it was reported on bugzilla, it would happen when plugging p54 usb device > > to RPi2. But, i'm not 100% sure that this patch will resolve the issue because > > the reporter didn't try my patch yet and I don't have the device to test. > > > > And there might be some other places calling the function without checking > > null pointer. The thing is that only the function don't check null among > > kfree functions. So, I just hope this patch will prevent potential oops > > issues. > > Okay, but your patch title was : "net: core: Prevent from > dereferencing null pointer when" > > "when" is usually followed by other words. Oh, sorry that was typo. I'll remove "when" from subject. Thanks, Myungho