netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Maxime Chevallier <maxime.chevallier@bootlin.com>
To: Andrew Lunn <andrew@lunn.ch>
Cc: Tobias Waldekranz <tobias@waldekranz.com>,
	davem@davemloft.net, kuba@kernel.org, marcin.s.wojtas@gmail.com,
	linux@armlinux.org.uk, edumazet@google.com, pabeni@redhat.com,
	ezequiel.garcia@free-electrons.com, netdev@vger.kernel.org
Subject: Re: [PATCH net] net: mvpp2: Prevent parser TCAM memory corruption
Date: Thu, 20 Mar 2025 18:27:38 +0100	[thread overview]
Message-ID: <20250320182738.67108ea4@fedora.home> (raw)
In-Reply-To: <16143c70-de5a-4f30-ad29-eae33d2e5b0b@lunn.ch>

On Thu, 20 Mar 2025 14:14:16 +0100
Andrew Lunn <andrew@lunn.ch> wrote:

> > We still need to disable bottom halves though, right?  Because otherwise
> > we could reach mvpp2_set_rx_mode() from net-rx by processing an IGMP/MLD
> > frame, for example.  
> 
> Ah, that answers the question i was asking myself. Why does RTNL not
> cover this...
> 
> Maybe the design was that RTNL is supposed to protect this, but things
> are happening outside of it? It would of helped if the code had put in
> some ASSERT_RTNL() calls to both indicate this was the idea, and to
> find cases where it was not actually true.

I think this was definitely missed. I added some of it back then, and I
certainly didn't consider non-rtnl protected paths. an ASSERT_RTNL
would've been a good idea indeed :(

With netdev_lock closing in, I think Tobias's approach is better. We
can't rely on a netdev_lock to protect the parser as it's shared
accross multiple netdevs.

Maxime

      parent reply	other threads:[~2025-03-20 17:27 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-03-20  9:17 [PATCH net] net: mvpp2: Prevent parser TCAM memory corruption Tobias Waldekranz
2025-03-20  9:57 ` Maxime Chevallier
2025-03-20 10:47   ` Tobias Waldekranz
2025-03-20 13:14     ` Andrew Lunn
2025-03-20 13:38       ` Tobias Waldekranz
2025-03-20 17:27       ` Maxime Chevallier [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=20250320182738.67108ea4@fedora.home \
    --to=maxime.chevallier@bootlin.com \
    --cc=andrew@lunn.ch \
    --cc=davem@davemloft.net \
    --cc=edumazet@google.com \
    --cc=ezequiel.garcia@free-electrons.com \
    --cc=kuba@kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=marcin.s.wojtas@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=tobias@waldekranz.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).