linux-kernel - Re: [PATCH net-next v25 08/13] net: add support for skbs with unreadable frags

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240909185748.0ac082fd@kernel.org>
Date: Mon, 9 Sep 2024 18:57:48 -0700
From: Jakub Kicinski <kuba@...nel.org>
To: Mina Almasry <almasrymina@...gle.com>
Cc: netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
 linux-doc@...r.kernel.org, linux-alpha@...r.kernel.org,
 linux-mips@...r.kernel.org, linux-parisc@...r.kernel.org,
 sparclinux@...r.kernel.org, linux-trace-kernel@...r.kernel.org,
 linux-arch@...r.kernel.org, bpf@...r.kernel.org,
 linux-kselftest@...r.kernel.org, linux-media@...r.kernel.org,
 dri-devel@...ts.freedesktop.org, Donald Hunter <donald.hunter@...il.com>,
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet
 <edumazet@...gle.com>, Paolo Abeni <pabeni@...hat.com>, Jonathan Corbet
 <corbet@....net>, Richard Henderson <richard.henderson@...aro.org>, Ivan
 Kokshaysky <ink@...assic.park.msu.ru>, Matt Turner <mattst88@...il.com>,
 Thomas Bogendoerfer <tsbogend@...ha.franken.de>, "James E.J. Bottomley"
 <James.Bottomley@...senPartnership.com>, Helge Deller <deller@....de>,
 Andreas Larsson <andreas@...sler.com>, Jesper Dangaard Brouer
 <hawk@...nel.org>, Ilias Apalodimas <ilias.apalodimas@...aro.org>, Steven
 Rostedt <rostedt@...dmis.org>, Masami Hiramatsu <mhiramat@...nel.org>,
 Mathieu Desnoyers <mathieu.desnoyers@...icios.com>, Arnd Bergmann
 <arnd@...db.de>, Steffen Klassert <steffen.klassert@...unet.com>, Herbert
 Xu <herbert@...dor.apana.org.au>, David Ahern <dsahern@...nel.org>, Willem
 de Bruijn <willemdebruijn.kernel@...il.com>, "Björn Töpel" <bjorn@...nel.org>, Magnus Karlsson
 <magnus.karlsson@...el.com>, Maciej Fijalkowski
 <maciej.fijalkowski@...el.com>, Jonathan Lemon <jonathan.lemon@...il.com>,
 Shuah Khan <shuah@...nel.org>, Alexei Starovoitov <ast@...nel.org>, Daniel
 Borkmann <daniel@...earbox.net>, John Fastabend <john.fastabend@...il.com>,
 Sumit Semwal <sumit.semwal@...aro.org>, "Christian König"
 <christian.koenig@....com>, Pavel Begunkov <asml.silence@...il.com>, David
 Wei <dw@...idwei.uk>, Jason Gunthorpe <jgg@...pe.ca>, Yunsheng Lin
 <linyunsheng@...wei.com>, Shailend Chand <shailend@...gle.com>, Harshitha
 Ramamurthy <hramamurthy@...gle.com>, Shakeel Butt <shakeel.butt@...ux.dev>,
 Jeroen de Borst <jeroendb@...gle.com>, Praveen Kaligineedi
 <pkaligineedi@...gle.com>, Bagas Sanjaya <bagasdotme@...il.com>, Christoph
 Hellwig <hch@...radead.org>, Nikolay Aleksandrov <razor@...ckwall.org>,
 Taehee Yoo <ap420073@...il.com>, Willem de Bruijn <willemb@...gle.com>,
 Kaiyuan Zhang <kaiyuanz@...gle.com>
Subject: Re: [PATCH net-next v25 08/13] net: add support for skbs with
 unreadable frags

On Mon,  9 Sep 2024 05:43:13 +0000 Mina Almasry wrote:
> For device memory TCP, we expect the skb headers to be available in host
> memory for access, and we expect the skb frags to be in device memory
> and unaccessible to the host. We expect there to be no mixing and
> matching of device memory frags (unaccessible) with host memory frags
> (accessible) in the same skb.
> 
> Add a skb->devmem flag which indicates whether the frags in this skb
> are device memory frags or not.
> 
> __skb_fill_netmem_desc() now checks frags added to skbs for net_iov,
> and marks the skb as skb->devmem accordingly.
> 
> Add checks through the network stack to avoid accessing the frags of
> devmem skbs and avoid coalescing devmem skbs with non devmem skbs.
> 
> Signed-off-by: Willem de Bruijn <willemb@...gle.com>
> Signed-off-by: Kaiyuan Zhang <kaiyuanz@...gle.com>
> Signed-off-by: Mina Almasry <almasrymina@...gle.com>
> Reviewed-by: Eric Dumazet <edumazet@...gle.com>

I'm sure we'll find more cases which need a check but I can't think 
of any now, so:

Reviewed-by: Jakub Kicinski <kuba@...nel.org>