From: Sowmini Varadhan <sowmini.varadhan@oracle•com>
To: Tom Herbert <tom@herbertland•com>
Cc: Eric Dumazet <eric.dumazet@gmail•com>,
Alexander Duyck <aduyck@mirantis•com>,
Linux Kernel Network Developers <netdev@vger•kernel.org>,
"David S. Miller" <davem@davemloft•net>,
Alexander Duyck <alexander.duyck@gmail•com>
Subject: Re: [net PATCH] flow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen
Date: Sat, 30 Jan 2016 14:12:20 -0500 [thread overview]
Message-ID: <20160130191220.GB11601@oracle.com> (raw)
In-Reply-To: <CALx6S378mozgF0A1iq=Y_LB+_5c=_8_iwOYBgoSArUJW60A6Ag@mail.gmail.com>
On (01/30/16 09:43), Tom Herbert wrote:
> That is not the only case, If a GRE TEB packet is ever received and
> flow dissector is called for any reason (like skb_get_hash) there's
> going to be problems-- and this doesn't require GRE to even be
> configured on the host.
>
> I have a patch that changes the 32-bit accesses in flow_dissector to
> use get_unaligned_be32. I don't have access to any machines that care
> about alignment (only x86). Do you know if there is an alternate way
> to test this other than running on architecture like Sparc?
I can help test this on sparc (would help if you send me any special
config instructions for the GRE TEB case) , but the other way to test
it would be something similar to this:
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -178,6 +178,8 @@ ip:
ip_proto = iph->protocol;
+ WARN_ON_ONCE(!IS_ALIGNED(iph->saddr, 4));
+
if (!dissector_uses_key(flow_dissector,
FLOW_DISSECTOR_KEY_IPV4_ADDRS))
next prev parent reply other threads:[~2016-01-30 19:12 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-29 18:06 [RFC] Kernel unaligned access at __skb_flow_dissect Sowmini Varadhan
2016-01-29 18:33 ` Eric Dumazet
2016-01-29 18:40 ` Eric Dumazet
2016-01-29 19:08 ` David Miller
2016-01-29 19:39 ` Eric Dumazet
2016-01-29 18:54 ` Eric Dumazet
2016-01-29 19:22 ` Sowmini Varadhan
2016-01-29 21:00 ` Tom Herbert
2016-01-29 21:09 ` Sowmini Varadhan
2016-01-29 21:33 ` Tom Herbert
2016-01-29 23:00 ` Tom Herbert
2016-01-29 23:04 ` Sowmini Varadhan
2016-01-29 23:31 ` Tom Herbert
2016-01-29 23:58 ` Sowmini Varadhan
2016-01-30 0:47 ` Tom Herbert
2016-01-30 1:18 ` David Miller
2016-01-30 2:15 ` Eric Dumazet
2016-01-31 22:13 ` Tom Herbert
2016-02-01 0:04 ` Eric Dumazet
2016-01-29 19:06 ` David Miller
2016-01-29 19:37 ` Eric Dumazet
2016-01-29 19:41 ` David Miller
2016-01-29 19:44 ` Sowmini Varadhan
2016-01-29 20:01 ` Eric Dumazet
2016-01-29 20:06 ` Eric Dumazet
2016-01-29 21:16 ` Alexander Duyck
2016-01-29 21:33 ` Eric Dumazet
2016-01-29 22:08 ` Alexander Duyck
2016-01-29 22:28 ` Eric Dumazet
2016-01-29 23:00 ` Alexander Duyck
2016-02-01 16:55 ` David Laight
2016-02-01 17:25 ` Eric Dumazet
2016-01-29 19:04 ` David Miller
2016-01-30 2:49 ` [net PATCH] flow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen Alexander Duyck
2016-01-30 3:23 ` Eric Dumazet
2016-01-30 3:35 ` David Miller
2016-01-30 4:46 ` Alexander Duyck
2016-01-30 16:17 ` Sowmini Varadhan
2016-01-30 17:43 ` Tom Herbert
2016-01-30 19:12 ` Sowmini Varadhan [this message]
2016-01-30 18:36 ` Alexander Duyck
2016-01-30 19:26 ` Eric Dumazet
2016-01-31 1:13 ` Alexander Duyck
2016-01-31 3:45 ` David Miller
2016-01-31 9:12 ` Alexander Duyck
2016-01-31 19:17 ` David Miller
2016-01-31 21:23 ` Sowmini Varadhan
2016-02-01 16:50 ` David Laight
2016-02-01 18:18 ` Alexander Duyck
2016-02-02 9:47 ` David Laight
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=20160130191220.GB11601@oracle.com \
--to=sowmini.varadhan@oracle$(echo .)com \
--cc=aduyck@mirantis$(echo .)com \
--cc=alexander.duyck@gmail$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=eric.dumazet@gmail$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=tom@herbertland$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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