Re: [Patch net, v2] net: xfrm: skip policies marked as dead while reinserting policies

[Herbert Xu]

On Tue, Aug 15, 2023 at 10:30:33AM +0300, Leon Romanovsky wrote:
>
> But policy has, and we are not interested in validity of it as first
> check in if (...) will be true for policy->walk.dead.
> 
> So it is safe to call to dir = xfrm_policy_id2dir(policy->index) even
> for dead policy.

If you dereference policy->index on a walker object it will read memory
before the start of the walker object.  That could do anything, perhaps
even triggering a page fault.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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