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From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@kernel.org>
To: Jesper Dangaard Brouer <hawk@kernel.org>, Alexei Starovoitov
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Subject: Re: [syzbot] [bpf?] [net?] general protection fault in dev_map_enqueue
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Date: Thu, 28 Mar 2024 21:39:48 +0100
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Jesper Dangaard Brouer <hawk@kernel.org> writes:

> On 27/03/2024 16.19, Alexei Starovoitov wrote:
>> Toke, Jesper,
>> 
>> please take a look.
>> It's reproducible 100% of the time.
>> dst is NULL in dev_map_enqueue().
>> 
>
> The `dst` (NULL) is basically `ri->tgt_value` being passed through
> (unmodified) via xdp_do_redirect_frame() and __xdp_do_redirect_frame()
> into dev_map_enqueue().
>
> I think something is wrong in xdp_test_run_batch().
> The `ri->tgt_value` is being set in __bpf_xdp_redirect_map(), but I
> cannot see __bpf_xdp_redirect_map() being used in xdp_test_run_batch().
>
> Toke, can you take a look at xdp_test_run_batch() and where
> `ri->tgt_value` is getting set?

Sure! I'm off for Easter, but I'll take a look when I get back next week :)

-Toke