From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com Message-ID: <4F3DD84B.30808@zytor.com> Date: Thu, 16 Feb 2012 20:32:11 -0800 From: "H. Peter Anvin" MIME-Version: 1.0 References: <1329422549-16407-1-git-send-email-wad@chromium.org> <1329422549-16407-3-git-send-email-wad@chromium.org> <4F3D61CB.2000301@zytor.com> <4F3D7250.6040504@zytor.com> <4F3D766E.7040205@zytor.com> <4F3D7DD4.6070103@zytor.com> <1329439809.2337.32.camel@localhost> <4F3DD39C.9090905@zytor.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: [kernel-hardening] Re: [PATCH v8 3/8] seccomp: add system call filtering using BPF To: Will Drewry Cc: Eric Paris , Markus Gutschke , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com, netdev@vger.kernel.org, x86@kernel.org, arnd@arndb.de, davem@davemloft.net, mingo@redhat.com, oleg@redhat.com, peterz@infradead.org, rdunlap@xenotime.net, mcgrathr@chromium.org, tglx@linutronix.de, luto@mit.edu, serge.hallyn@canonical.com, djm@mindrot.org, scarybeasts@gmail.com, indan@nul.nu, pmoore@redhat.com, akpm@linux-foundation.org, corbet@lwn.net, eric.dumazet@gmail.com, keescook@chromium.org List-ID: On 02/16/2012 08:26 PM, Will Drewry wrote: >> >> For x32 you have the option of introducing a new value or relying on bit >> 30 in eax (and AUDIT_ARCH_X86_64). The latter is more natural, probably. > > Will that bit be visible as the syscall number or will it be stripped > out before passing the number around? If it's visible, then it > doesn't seem like there'd need to be a new AUDIT_ARCH, but I suspect > someone like Eric will have an actually useful opinion. > Bit 30 is visible in orig_eax; whether you export it as part of "the syscall number" is presumably TBD, but I think it's more natural to do so. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH v8 3/8] seccomp: add system call filtering using BPF Date: Thu, 16 Feb 2012 20:32:11 -0800 Message-ID: <4F3DD84B.30808@zytor.com> References: <1329422549-16407-1-git-send-email-wad@chromium.org> <1329422549-16407-3-git-send-email-wad@chromium.org> <4F3D61CB.2000301@zytor.com> <4F3D7250.6040504@zytor.com> <4F3D766E.7040205@zytor.com> <4F3D7DD4.6070103@zytor.com> <1329439809.2337.32.camel@localhost> <4F3DD39C.9090905@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-doc-owner@vger.kernel.org To: Will Drewry Cc: Eric Paris , Markus Gutschke , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com, netdev@vger.kernel.org, x86@kernel.org, arnd@arndb.de, davem@davemloft.net, mingo@redhat.com, oleg@redhat.com, peterz@infradead.org, rdunlap@xenotime.net, mcgrathr@chromium.org, tglx@linutronix.de, luto@mit.edu, serge.hallyn@canonical.com, djm@mindrot.org, scarybeasts@gmail.com, indan@nul.nu, pmoore@redhat.com, akpm@linux-foundation.org, corbet@lwn.net, eric.dumazet@gmail.com, keescook@chromium.org List-Id: linux-arch.vger.kernel.org On 02/16/2012 08:26 PM, Will Drewry wrote: >> >> For x32 you have the option of introducing a new value or relying on bit >> 30 in eax (and AUDIT_ARCH_X86_64). The latter is more natural, probably. > > Will that bit be visible as the syscall number or will it be stripped > out before passing the number around? If it's visible, then it > doesn't seem like there'd need to be a new AUDIT_ARCH, but I suspect > someone like Eric will have an actually useful opinion. > Bit 30 is visible in orig_eax; whether you export it as part of "the syscall number" is presumably TBD, but I think it's more natural to do so. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.