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Date:   Mon, 30 Oct 2023 15:05:12 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Frederik Deweerdt <deweerdt.lkml@gmail.com>
Cc:     linux-kernel@vger.kernel.org
Subject: Re: [PATCH] [RFC] Add missing NULL check in
 `tls_strp_check_queue_ok`
Message-ID: <20231030150512.254220a5@kernel.org>
In-Reply-To: <ZUAmyb44sy309V6H@urola>
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On Mon, 30 Oct 2023 14:57:29 -0700 Frederik Deweerdt wrote:
> We see `tls_strp_check_queue_ok` running into a NULL deref when
> evaluating `TCP_SKB_CB(skb)->seq`.
> 
> This commit attempts to address the issue by exiting the loop if
> skb->next is NULL, and has proven stable under load.
> 
> That said i don't understand the code enough to convince myself that
> the NULL check is indeed required, and i would be happy gather data if
> that's useful.

Hm. Can you share the decoded stack trace?