From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Jakub Kicinski <kuba@kernel.org>
Cc: joao@overdrivepizza.com, netfilter-devel@vger.kernel.org,
coreteam@netfilter.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org, kadlec@netfilter.org, fw@strlen.de,
davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
rkannoth@marvell.com, wojciech.drewek@intel.com,
steen.hegenlund@microhip.com, keescook@chromium.org,
Joao Moreira <joao.moreira@intel.com>
Subject: Re: [PATCH 0/2] Prevent potential write out of bounds
Date: Fri, 1 Sep 2023 10:15:06 +0200 [thread overview]
Message-ID: <ZPGdihJLKXOj7rDI@calendula> (raw)
In-Reply-To: <20230831182800.25e5d4d9@kernel.org>
On Thu, Aug 31, 2023 at 06:28:00PM -0700, Jakub Kicinski wrote:
> On Thu, 31 Aug 2023 18:04:35 -0700 joao@overdrivepizza.com wrote:
> > The function flow_rule_alloc in net/core/flow_offload.c [2] gets an
> > unsigned int num_actions (line 10) and later traverses the actions in
> > the rule (line 24) setting hw.stats to FLOW_ACTION_HW_STATS_DONT_CARE.
> >
> > Within the same file, the loop in the line 24 compares a signed int
> > (i) to an unsigned int (num_actions), and then uses i as an array
> > index. If an integer overflow happens, then the array within the loop
> > is wrongly indexed, causing a write out of bounds.
> >
> > After checking with maintainers, it seems that the front-end caps the
> > maximum value of num_action, thus it is not possible to reach the given
> > write out of bounds, yet, still, to prevent disasters it is better to
> > fix the signedness here.
>
> How did you find this? The commit messages should include info
> about how the issue was discovered.
This is net-next material IMO, none of the existing interfaces uses
such a large number of actions for this to be an issue.
prev parent reply other threads:[~2023-09-01 8:15 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-01 1:04 [PATCH 0/2] Prevent potential write out of bounds joao
2023-09-01 1:04 ` [PATCH 1/2] Make loop indexes unsigned joao
2023-09-01 1:04 ` [PATCH 2/2] Ensure num_actions is not a negative joao
2023-09-01 8:58 ` Pablo Neira Ayuso
2023-09-01 1:28 ` [PATCH 0/2] Prevent potential write out of bounds Jakub Kicinski
2023-09-01 5:46 ` Joao Moreira
2023-09-01 8:15 ` Pablo Neira Ayuso [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=ZPGdihJLKXOj7rDI@calendula \
--to=pablo@netfilter.org \
--cc=coreteam@netfilter.org \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=fw@strlen.de \
--cc=joao.moreira@intel.com \
--cc=joao@overdrivepizza.com \
--cc=kadlec@netfilter.org \
--cc=keescook@chromium.org \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=netfilter-devel@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=rkannoth@marvell.com \
--cc=steen.hegenlund@microhip.com \
--cc=wojciech.drewek@intel.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;
as well as URLs for NNTP newsgroup(s).