From: Alexei Starovoitov <ast@plumgrid.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>,
Ingo Molnar <mingo@kernel.org>,
"David S. Miller" <davem@davemloft.net>,
Andy Lutomirski <luto@amacapital.net>,
Hannes Frederic Sowa <hannes@stressinduktion.org>,
Eric Dumazet <edumazet@google.com>,
Kees Cook <keescook@chromium.org>,
linux-api@vger.kernel.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next 1/2] bpf: enable non-root eBPF programs
Date: Tue, 6 Oct 2015 12:26:53 -0700 [thread overview]
Message-ID: <5614207D.4050708@plumgrid.com> (raw)
In-Reply-To: <1444154160.9555.5.camel@edumazet-glaptop2.roam.corp.google.com>
On 10/6/15 10:56 AM, Eric Dumazet wrote:
> On Tue, 2015-10-06 at 10:50 -0700, Alexei Starovoitov wrote:
>
>> was also thinking that we can do it only in paths that actually
>> have multiple protocol layers, since today bpf is mainly used with
>> tcpdump(raw_socket) and new af_packet fanout both have cb cleared
>> on RX, because it just came out of alloc_skb and no layers were called,
>> and on TX we can clear 20 bytes in dev_queue_xmit_nit().
>> af_unix/netlink also have clean skb. Need to analyze tun and sctp...
>> but it feels overly fragile to save a branch in sk_filter,
>> so planning to go with
>> if(unlikely(prog->cb_access)) memset in sk_filter().
>>
>
> This will break TCP use of sk_filter().
> skb->cb[] contains useful data in TCP layer.
oops. thanks for catching. In case of sk_filter on top of tcp sock,
it shouldn't be looking at cb at all.
I'm thinking to send a patch to get rid of cb access for socket filters
all together until better solution found.
next prev parent reply other threads:[~2015-10-06 19:26 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-05 20:48 [PATCH net-next 0/2] bpf: unprivileged Alexei Starovoitov
2015-10-05 20:48 ` [PATCH net-next 1/2] bpf: enable non-root eBPF programs Alexei Starovoitov
2015-10-05 22:14 ` Daniel Borkmann
[not found] ` <5612F639.2050305-FeC+5ew28dpmcu3hnIyYJQ@public.gmane.org>
2015-10-06 0:51 ` Alexei Starovoitov
[not found] ` <56131B1F.80002-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-10-06 7:13 ` Ingo Molnar
2015-10-06 8:05 ` Daniel Borkmann
2015-10-06 8:20 ` Ingo Molnar
[not found] ` <20151006082048.GA18287-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2015-10-06 8:39 ` Daniel Borkmann
[not found] ` <561388D1.30406-FeC+5ew28dpmcu3hnIyYJQ@public.gmane.org>
2015-10-06 17:50 ` Alexei Starovoitov
2015-10-06 17:56 ` Eric Dumazet
[not found] ` <1444154160.9555.5.camel-XN9IlZ5yJG9HTL0Zs8A6p/gx64E7kk8eUsxypvmhUTTZJqsBc5GL+g@public.gmane.org>
2015-10-06 18:05 ` Andy Lutomirski
2015-10-07 6:05 ` Ingo Molnar
2015-10-06 19:26 ` Alexei Starovoitov [this message]
[not found] ` <561409EC.5050005-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-10-06 18:03 ` Daniel Borkmann
2015-10-06 12:45 ` Daniel Borkmann
2015-10-07 21:20 ` Alexei Starovoitov
[not found] ` <56158CAF.9030209-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-10-07 22:07 ` Daniel Borkmann
2015-10-07 22:22 ` Kees Cook
2015-10-07 23:49 ` Alexei Starovoitov
[not found] ` <5615AF92.50402-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-10-08 6:21 ` Ingo Molnar
2015-10-08 6:30 ` Alexei Starovoitov
2015-10-08 17:42 ` Kees Cook
[not found] ` <1444078101-29060-2-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-10-05 21:00 ` Kees Cook
2015-10-05 21:12 ` Alexei Starovoitov
[not found] ` <5612E7C4.1010306-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-10-05 21:16 ` Andy Lutomirski
2015-10-05 21:32 ` Alexei Starovoitov
2015-10-05 22:02 ` Kees Cook
2015-10-06 0:28 ` Alexei Starovoitov
2015-10-08 2:29 ` Alexei Starovoitov
2015-10-05 20:48 ` [PATCH net-next 2/2] bpf: charge user for creation of BPF maps and programs Alexei Starovoitov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5614207D.4050708@plumgrid.com \
--to=ast@plumgrid.com \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=eric.dumazet@gmail.com \
--cc=hannes@stressinduktion.org \
--cc=keescook@chromium.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=mingo@kernel.org \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).