From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [RESEND v4 2/6] remoteproc: debugfs: Add ability to boot remote processor using debugfs Date: Thu, 03 Dec 2015 22:12:59 +0100 Message-ID: <2473673.tSymyNlg3h@wuerfel> References: <1448370862-19120-1-git-send-email-lee.jones@linaro.org> <2600153.9u9Z7N2IT1@wuerfel> <20151203172830.GB26902@x1> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <20151203172830.GB26902@x1> Sender: linux-kernel-owner@vger.kernel.org To: linux-arm-kernel@lists.infradead.org Cc: Lee Jones , Ohad Ben-Cohen , "devicetree@vger.kernel.org" , Florian Fainelli , kernel@stlinux.com, Nathan_Lynch@mentor.com, "linux-kernel@vger.kernel.org" , Bjorn Andersson , ludovic.barre@st.com, Maxime Coquelin List-Id: devicetree@vger.kernel.org On Thursday 03 December 2015 17:28:30 Lee Jones wrote: > > > > Ah, interesting. I haven't tried myself, and just tried to read the > > code. Maybe glibc already catches zero-length writes before it gets > > into the kernel, or I just missed the part of the syscall that checks > > for this. > > Glibc is responsible indeed: > > http://osxr.org/glibc/source/io/write.c Ok, so an attacker can force the stack overflow by calling syscall(__NR_write, fd, p, 0) if that has any potential value, but normal users won't hit this case. Arnd