Re: [PATCH net] dccp: check for ccid in ccid_hc_tx_send_packet

[Paolo Abeni]

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")
> 
> Reported-by: syzbot+c71bc336c5061153b502@xxxxxxxxxxxxxxxxxxxxxxxxx
> Closes: https://syzkaller.appspot.com/bug?extid=c71bc336c5061153b502

and add a suitable fixes here.

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

Thanks!

Paolo