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Message-ID: <f41c06eafd983584647e7d61561ea6282cdb735e.camel@redhat.com>
Subject: Re: [PATCH net] dccp: check for ccid in ccid_hc_tx_send_packet
From:   Paolo Abeni <pabeni@redhat.com>
To:     Bragatheswaran Manickavel <bragathemanick0908@gmail.com>,
        davem@davemloft.net, edumazet@google.com, kuba@kernel.org
Cc:     dccp@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        syzbot+c71bc336c5061153b502@syzkaller.appspotmail.com
Date:   Thu, 02 Nov 2023 12:14:53 +0100
In-Reply-To: <20231028144136.3462-1-bragathemanick0908@gmail.com>
References: <20231028144136.3462-1-bragathemanick0908@gmail.com>
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On Sat, 2023-10-28 at 20:11 +0530, Bragatheswaran Manickavel wrote:
> ccid_hc_tx_send_packet might be called with a NULL ccid pointer
> leading to a NULL pointer dereference

You should describe how such event could happen.

> Below mentioned commit has similarly changes
> commit 276bdb82dedb ("dccp: check ccid before dereferencing")
>=20
> Reported-by: syzbot+c71bc336c5061153b502@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=3Dc71bc336c5061153b502

and add a suitable fixes here.

(beyond taking care of other critical code paths, as reported by Eric).

Thanks!

Paolo