From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com From: David Howells In-Reply-To: <20160628094357.GA16467@gondor.apana.org.au> References: <20160628094357.GA16467@gondor.apana.org.au> <20160628075546.GA15690@gondor.apana.org.au> <1eeb00c5098d8096cdb61dc7ee1ddc61b3e80f9e.1466974736.git.luto@kernel.org> <699.1467100340@warthog.procyon.org.uk> <4339.1467104063@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <14864.1467108030.1@warthog.procyon.org.uk> Date: Tue, 28 Jun 2016 11:00:30 +0100 Message-ID: <14865.1467108030@warthog.procyon.org.uk> Subject: [kernel-hardening] Re: [PATCH v4 02/29] rxrpc: Avoid using stack memory in SG lists in rxkad To: Herbert Xu Cc: dhowells@redhat.com, Andy Lutomirski , x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Borislav Petkov , Nadav Amit , Kees Cook , Brian Gerst , "kernel-hardening@lists.openwall.com" , Linus Torvalds , Josh Poimboeuf , Jann Horn , Heiko Carstens List-ID: Herbert Xu wrote: > > I'm using the per-skb state for my own purposes and might be looking at it > > elsewhere at the same time. > > AFAICS this cannot happen for secure_packet/verify_packet. In both > cases we have exclusive ownership of the skb. In code I'm busy working on the patch I'm decrypting may be on the receive queue several times. rxrpc has a jumbo packet concept whereby a packet may be constructed in such a way that it's actually several packets stitched together - the idea being that a router can split it up (not that any actually do that I know of) - but each segment of the jumbo packet may be enqueued as a separate entity. > But it's your code so feel free to send your own patch. I will apply something very similar to my tree. Andy's patch does not apply as-is due to conflicts. David From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Subject: Re: [PATCH v4 02/29] rxrpc: Avoid using stack memory in SG lists in rxkad Date: Tue, 28 Jun 2016 11:00:30 +0100 Message-ID: <14865.1467108030@warthog.procyon.org.uk> References: <20160628094357.GA16467@gondor.apana.org.au> <20160628075546.GA15690@gondor.apana.org.au> <1eeb00c5098d8096cdb61dc7ee1ddc61b3e80f9e.1466974736.git.luto@kernel.org> <699.1467100340@warthog.procyon.org.uk> <4339.1467104063@warthog.procyon.org.uk> Reply-To: kernel-hardening@lists.openwall.com Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: List-Post: List-Help: List-Unsubscribe: List-Subscribe: In-Reply-To: <20160628094357.GA16467@gondor.apana.org.au> Content-ID: <14864.1467108030.1@warthog.procyon.org.uk> To: Herbert Xu Cc: dhowells@redhat.com, Andy Lutomirski , x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Borislav Petkov , Nadav Amit , Kees Cook , Brian Gerst , "kernel-hardening@lists.openwall.com" , Linus Torvalds , Josh Poimboeuf , Jann Horn , Heiko Carstens List-Id: linux-arch.vger.kernel.org Herbert Xu wrote: > > I'm using the per-skb state for my own purposes and might be looking at it > > elsewhere at the same time. > > AFAICS this cannot happen for secure_packet/verify_packet. In both > cases we have exclusive ownership of the skb. In code I'm busy working on the patch I'm decrypting may be on the receive queue several times. rxrpc has a jumbo packet concept whereby a packet may be constructed in such a way that it's actually several packets stitched together - the idea being that a router can split it up (not that any actually do that I know of) - but each segment of the jumbo packet may be enqueued as a separate entity. > But it's your code so feel free to send your own patch. I will apply something very similar to my tree. Andy's patch does not apply as-is due to conflicts. David