Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933532AbaKMPGg (ORCPT ); Thu, 13 Nov 2014 10:06:36 -0500 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:57609 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933261AbaKMPGe (ORCPT ); Thu, 13 Nov 2014 10:06:34 -0500 Date: Thu, 13 Nov 2014 15:06:25 +0000 From: Catalin Marinas To: Kyle McMartin Cc: "linux-kernel@vger.kernel.org" , "pmatouse@redhat.com" , Will Deacon , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH] arm64: __clear_user: handle exceptions on strb Message-ID: <20141113150624.GB18494@e104818-lin.cambridge.arm.com> References: <20141112210744.GC6869@redacted.bos.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141112210744.GC6869@redacted.bos.redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 12, 2014 at 09:07:44PM +0000, Kyle McMartin wrote: > ARM64 currently doesn't fix up faults on the single-byte (strb) case of > __clear_user... which means that we can cause a nasty kernel panic as an > ordinary user with any multiple PAGE_SIZE+1 read from /dev/zero. > i.e.: dd if=/dev/zero of=foo ibs=1 count=1 (or ibs=65537, etc.) Thanks for this, it's been like this for a while. Applied. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/