From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH] arm/arm64: KVM: Feed initialized memory to MMIO accesses Date: Wed, 24 Feb 2016 12:06:52 +0000 Message-ID: <56CD9CDC.2020100@arm.com> References: <1455723260-23793-1-git-send-email-marc.zyngier@arm.com> <20160224114044.GA18451@cbox> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org To: Christoffer Dall Return-path: In-Reply-To: <20160224114044.GA18451@cbox> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org On 24/02/16 11:40, Christoffer Dall wrote: > On Wed, Feb 17, 2016 at 03:34:20PM +0000, Marc Zyngier wrote: >> On an MMIO access, we always copy the on-stack buffer info >> the shared "run" structure, even if this is a read access. >> This ends up leaking up to 8 bytes of uninitialized memory >> into userspace. > > I think it only leaks 'len' bytes to userspace ;) > >> >> An obvious fix for this one is to only perform the copy if >> this is an actual write. > > Reviewed-by: Christoffer Dall Thanks. I've pushed this onto master, with a view of sending a PR to Paolo this evening (hopefully the last one for this cycle). M. -- Jazz is not dead. It just smells funny...