linux-kernel - Re: [PATCH net-next] ip, ip6: Fix splice to raw and ping sockets

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: <20230615222327.15e85c55@kernel.org>
Date:   Thu, 15 Jun 2023 22:23:27 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Willem de Bruijn <willemdebruijn.kernel@...il.com>
Cc:     David Howells <dhowells@...hat.com>, netdev@...r.kernel.org,
        syzbot+d8486855ef44506fd675@...kaller.appspotmail.com,
        David Ahern <dsahern@...nel.org>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Paolo Abeni <pabeni@...hat.com>, Jens Axboe <axboe@...nel.dk>,
        Matthew Wilcox <willy@...radead.org>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next] ip, ip6: Fix splice to raw and ping sockets

On Wed, 14 Jun 2023 09:04:16 +0100 David Howells wrote:
> Splicing to SOCK_RAW sockets may set MSG_SPLICE_PAGES, but in such a case,
> __ip_append_data() will call skb_splice_from_iter() to access the 'from'
> data, assuming it to point to a msghdr struct with an iter, instead of
> using the provided getfrag function to access it.
> 
> In the case of raw_sendmsg(), however, this is not the case and 'from' will
> point to a raw_frag_vec struct and raw_getfrag() will be the frag-getting
> function.  A similar issue may occur with rawv6_sendmsg().
> 
> Fix this by ignoring MSG_SPLICE_PAGES if getfrag != ip_generic_getfrag as
> ip_generic_getfrag() expects "from" to be a msghdr*, but the other getfrags
> don't.  Note that this will prevent MSG_SPLICE_PAGES from being effective
> for udplite.
> 
> This likely affects ping sockets too.  udplite looks like it should be okay
> as it expects "from" to be a msghdr.

Willem, looks good?