From: Martin KaFai Lau <kafai@fb.com>
To: Phil Sutter <phil@nwl.cc>
Cc: <netdev@vger.kernel.org>,
Hannes Frederic Sowa <hannes@stressinduktion.org>,
Steffen Klassert <steffen.klassert@secunet.com>,
Julian Anastasov <ja@ssi.bg>
Subject: Re: NULL pointer dereference in rt6_get_cookie()
Date: Wed, 14 Oct 2015 16:17:05 -0700 [thread overview]
Message-ID: <20151014231705.GA79022@kafai-mba.local> (raw)
In-Reply-To: <20151014223314.C029E20077@mail.nwl.cc>
On Thu, Oct 15, 2015 at 12:34:13AM +0200, Phil Sutter wrote:
> Hi Martin,
>
> On Tue, Oct 13, 2015 at 11:14:21PM -0700, Martin KaFai Lau wrote:
> > On Tue, Oct 13, 2015 at 09:26:41PM +0200, Phil Sutter wrote:
> > > I have backed up the rt pointer at top of the function and restored it
> > > before pr_err, this is the output:
> > >
> > > | rt6i_dst:2001:4dd0:ff3b:13::/64 rt6i_gateway::: rt6i_flags:40000001 dst.flags:00000000
> > Hi Phil, Can you try the following patch and report the pr_err?
>
> Probably needless to say, but with your patch applied the Oops does not
> occur anymore. This is the log output:
Thanks for testing it. The patch may need a bit refactoring work and
I will post it soon.
>
> | [ 46.518869] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 46.518874] IPv6: rt:ffff8800cb07a000 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 46.529171] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 46.529174] IPv6: rt:ffff8800cb07b500 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 46.529187] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 46.529189] IPv6: rt:ffff8800cb07ad80 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 47.532014] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 47.532021] IPv6: rt:ffff8800cb07a000 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 47.532028] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 47.532031] IPv6: rt:ffff8800cb07b500 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 49.536010] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 49.536014] IPv6: rt:ffff8800cb07ad80 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 49.536021] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 49.536024] IPv6: rt:ffff8800cb07a180 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 53.544013] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 53.544020] IPv6: rt:ffff8800cb07a300 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
> | [ 53.544028] IPv6: ort:ffff8800cbb5b800 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:40000001 dst.flags:00000020
> | [ 53.544031] IPv6: rt:ffff8800cb07b980 rt6i_dst:[2001:4dd0:ff3b:13::]/64 rt6i_gateway:[::] rt6i_flags:00000001 dst.flags:00000000
>
> In case the amount of log entries is surprising: my test-case is
> mounting two NFS shares over IPsec. No idea if that's relevant or not.
I also don't know why xfrm_lookup() errors out and then triggers
make_blackhole() but I believe it should not affect the fix here.
Thanks,
Martin
prev parent reply other threads:[~2015-10-14 23:17 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-10 13:24 NULL pointer dereference in rt6_get_cookie() Phil Sutter
2015-10-12 20:31 ` Martin KaFai Lau
2015-10-13 18:14 ` Martin KaFai Lau
2015-10-13 19:10 ` Phil Sutter
2015-10-13 19:30 ` Martin KaFai Lau
[not found] ` <20151013191039.GA3070@base.sg13b.nwl.cc>
2015-10-13 19:26 ` Phil Sutter
2015-10-14 6:14 ` Martin KaFai Lau
2015-10-14 22:34 ` Phil Sutter
2015-10-14 23:17 ` Martin KaFai Lau [this message]
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=20151014231705.GA79022@kafai-mba.local \
--to=kafai@fb.com \
--cc=hannes@stressinduktion.org \
--cc=ja@ssi.bg \
--cc=netdev@vger.kernel.org \
--cc=phil@nwl.cc \
--cc=steffen.klassert@secunet.com \
/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