From mboxrd@z Thu Jan 1 00:00:00 1970 From: chunfeng yun Subject: Re: [PATCH] usb: core: buffer: avoid NULL pointer dereferrence Date: Wed, 27 Apr 2016 09:32:10 +0800 Message-ID: <1461720730.11651.4.camel@mhfsdcap03> References: <20160408140701.GA3547@kroah.com> <20160426231115.GB23273@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160426231115.GB23273-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Greg Kroah-Hartman Cc: Alan Stern , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-mediatek@lists.infradead.org Hi, On Tue, 2016-04-26 at 16:11 -0700, Greg Kroah-Hartman wrote: > On Fri, Apr 08, 2016 at 11:21:05AM -0400, Alan Stern wrote: > > On Fri, 8 Apr 2016, Greg Kroah-Hartman wrote: > > > > > On Fri, Apr 08, 2016 at 05:08:03PM +0800, Chunfeng Yun wrote: > > > > NULL pointer dereferrence will happen when class driver > > > > wants to allocate zero length buffer and pool_max[0] > > > > can't be used, so skip reserved pool in this case. > > > > > > Why would a driver want to allocate a 0 length buffer? What driver does > > > this? > > > > > > Shouldn't we fix that issue instead? > > > > And even if a driver does want to allocate a 0-length buffer, shouldn't > > the function simply return early instead of running through all its > > calculations? > > Yes it should, Chunfeng, can you fix this patch to do that please. > Ok, I will fix it later > thanks, > > greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html