From: Simon Horman <horms@kernel.org>
To: Yeounsu Moon <yyyynoom@gmail.com>
Cc: 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>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: dlink: fix null dereference in receive_packet()
Date: Fri, 10 Oct 2025 08:18:35 +0100 [thread overview]
Message-ID: <20251010071835.GB3115768@horms.kernel.org> (raw)
In-Reply-To: <20251009190222.4777-1-yyyynoom@gmail.com>
On Fri, Oct 10, 2025 at 04:02:22AM +0900, Yeounsu Moon wrote:
> If `np->rx_skbuff[entry]` was not allocated before
> reuse, `receive_packet()` will cause null dereference.
>
> This patch fixes the issue by breaking out of the loop when
> `np->rx_skbuff[entry]` is `NULL`.
I see that if np->rx_skbuff[entry] there will be a dereference.
But I'm less clear on how this situation can occur.
So I think it would be worth adding some explanation of that
to the commit message.
Also, I do see that break will result in np->rx_skbuff[entry],
and other empty entries in that array, being refilled.
This is due to the refill loop that towards the end of receive_packet().
But perhaps it is worth mentioning that in the commit message too?
>
> Found by inspection.
Thanks, that is clear.
>
> Signed-off-by: Yeounsu Moon <yyyynoom@gmail.com>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Tested-on: D-Link DGE-550T Rev-A3
...
next prev parent reply other threads:[~2025-10-10 7:18 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-09 19:02 [PATCH net] net: dlink: fix null dereference in receive_packet() Yeounsu Moon
2025-10-10 7:18 ` Simon Horman [this message]
2025-10-10 16:58 ` Yeounsu Moon
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