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From: Simon Horman <horms@kernel.org>
To: Alexey Kodanev <aleksei.kodanev@bell-sw.com>
Cc: netdev@vger.kernel.org, Byungho An <bh74.an@samsung.com>,
	Andrew Lunn <andrew+netdev@lunn.ch>,
	"David S . Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Girish K S <ks.giri@samsung.com>,
	Siva Reddy <siva.kallam@samsung.com>,
	Vipul Pandya <vipul.pandya@samsung.com>
Subject: Re: [PATCH net] net: sxgbe: fix potential NULL dereference in sxgbe_rx()
Date: Tue, 25 Nov 2025 15:15:49 +0000	[thread overview]
Message-ID: <aSXIJZ3EztBeCfPg@horms.kernel.org> (raw)
In-Reply-To: <20251121123834.97748-1-aleksei.kodanev@bell-sw.com>

On Fri, Nov 21, 2025 at 12:38:34PM +0000, Alexey Kodanev wrote:
> Currently, when skb is null, the driver prints an error and then
> dereferences skb on the next line.
> 
> To fix this, let's add a 'break' after the error message to switch
> to sxgbe_rx_refill(), which is similar to the approach taken by the
> other drivers in this particular case, e.g. calxeda with xgmac_rx().
> 
> Found during a code review.
> 
> Fixes: 1edb9ca69e8a ("net: sxgbe: add basic framework for Samsung 10Gb ethernet driver")
> Signed-off-by: Alexey Kodanev <aleksei.kodanev@bell-sw.com>

Thanks Alexey,

I think this is a case where it is hard to know the true effects
without running the system. But I'm assuming that we aren't in
a position to do so. So instead we need to try to reason at
the code level.

From that perspective I do see that:
1. Without this change there will be a NULL pointer dereference *boob*
2. It seems that the refill logic should work with the proposed solution

So, I do expect this helps.
And I do think it can be accepted without hw testing.
But I do have a lower confidence level than I would if there
was hw testing.

Reviewed-by: Simon Horman <horms@kernel.org>

  reply	other threads:[~2025-11-25 15:15 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-21 12:38 [PATCH net] net: sxgbe: fix potential NULL dereference in sxgbe_rx() Alexey Kodanev
2025-11-25 15:15 ` Simon Horman [this message]
2025-11-26  3:20 ` patchwork-bot+netdevbpf

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