Re: [PATCH] io_uring/rsrc: fix slab-out-of-bounds in io_buffer_register_bvec

[Jens Axboe]

On 12/18/25 4:00 PM, Keith Busch wrote:
> On Thu, Dec 18, 2025 at 01:13:11AM +0000, veygax wrote:
>> On 18/12/2025 00:56, Keith Busch wrote:
>>> I believe you're supposed to use the bio_add_page() API rather than open
>>> code the bvec setup.
>>
>> True, but I wanted fine control to prove my theory
> 
> But doesn't that just prove misusing the interface breaks things? Is
> there currently a legit way to get this error without the misuse? Or is
> there existing mis-use in the kernel that should be fixed instead?

This is the big question, and also why I originally rejected the posted
poc as it's not a valid use case.

veygax, please make a real reproducer or detail how this can actually
happen with the exposed APIs.

-- 
Jens Axboe