From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [RESEND v4 2/6] remoteproc: debugfs: Add ability to boot remote processor using debugfs Date: Fri, 4 Dec 2015 08:24:27 +0000 Message-ID: <20151204082427.GC26902@x1> References: <1448370862-19120-1-git-send-email-lee.jones@linaro.org> <2600153.9u9Z7N2IT1@wuerfel> <20151203172830.GB26902@x1> <2473673.tSymyNlg3h@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <2473673.tSymyNlg3h@wuerfel> Sender: linux-kernel-owner@vger.kernel.org To: Arnd Bergmann Cc: linux-arm-kernel@lists.infradead.org, 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 Thu, 03 Dec 2015, Arnd Bergmann wrote: > On Thursday 03 December 2015 17:28:30 Lee Jones wrote: > > >=20 > > > Ah, interesting. I haven't tried myself, and just tried to read t= he > > > code. Maybe glibc already catches zero-length writes before it ge= ts > > > into the kernel, or I just missed the part of the syscall that ch= ecks > > > for this. > >=20 > > Glibc is responsible indeed: > > =20 > > http://osxr.org/glibc/source/io/write.c >=20 > 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. Right. I have fixed the issue (and another one I found) anyway, if only to rid the GCC warning. --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog