Re: [PATCH] RDMA/rxe: Reject prefetch of a non-ODP MR

[Norbert Szetei <norbert@doyensec.com>]

On Sep 6, 2026, at 11:01, Leon Romanovsky <leon@kernel.org> wrote:
>>> 
>> Do you mean lookup_mr() should take IB_ACCESS_ON_DEMAND into account, so that
>> the existing (access & mr->access) != access test rejects the non-ODP MR?
> 
> I expected lookup_mr(..., IB_ACCESS_ON_DEMAND) to be called and to
> perform all the necessary checks internally.

Done in v2.

>> rxe_rereg_user_mr() with IB_MR_REREG_ACCESS assigns mr->access directly, and
>> IB_ACCESS_ON_DEMAND is part of RXE_ACCESS_SUPPORTED_MR. So userspace can set
>> that flag on a plain MR after registration, without the umem changing. Am I
>> missing something there?
> 
> I assume this is a bug that needs to be fixed.

OK, I just sent the series that includes that too. It depends on ae36a5b609ae 
("RDMA/rxe: validate access flags before swapping the MR's PD"), which moved 
the validation above the mr->ibmr.pd swap. v2 is based on for-rc.

N.

> Thanks
> 
>> 
>> Thanks.
>> 
>>> 
>>> Thanks.