Re: [PATCH 6.6.y v2 0/3] ksmbd: validate owner of durable handle on reconnect

[Alva Lan <alvalan9@foxmail.com>]

On 5/25/2026 11:33 PM, Sasha Levin wrote:
> On Mon, May 25, 2026 at 06:38:58PM +0800, Alva Lan wrote:
>> This series backports three upstream commits to the 6.6.y stable branch
>> to address CVE-2026-31717.
>>
>> Upstream commits:
>> - 098c0ac3808c ("ksmbd: avoid reclaiming expired durable opens by the client")
>> - 894947e0736d ("ksmbd: add durable scavenger timer")
>> - 49110a8ce654 ("ksmbd: validate owner of durable handle on reconnect")
> Two notes before this can be queued:
>
> 1. The short SHAs in the cover letter for patches 1 and 2 do not resolve
>     in mainline. The correct upstream SHAs are 520da3c488c5 ("ksmbd:
>     avoid reclaiming expired durable opens by the client") and
>     d484d621d40f ("ksmbd: add durable scavenger timer"). Please fix the
>     cover letter on the next spin.
>
> 2. More importantly, this series adds the durable scavenger
>     (d484d621d40f) without its critical follow-up bf736184d063d ("ksmbd:
>     close durable scavenger races against m_fp_list lookups", Fixes:
>     d484d621d40f). That follow-up closes two KASAN-validated bugs in
>     the scavenger code: an fp->node list-head reuse that corrupts
>     f_ci->m_fp_list via list_add(&fp->node, &scavenger_list), and a
>     refcount race between scavenger qualification under global_ft.lock
>     and m_fp_list walkers that races to a UAF. Please include
>     bf736184d063d in the next revision so we are not knowingly queuing
>     the scavenger with these races still open.
>
> Also, given the patches are authored by Namjae, an Acked-by from him
> on the 6.6.y adaptation would be helpful before I pick this up.

Thanks for your review. I will add bf736184d063 ("ksmbd: close durable 
scavenger races against m_fp_list lookups")

in my v3 backport.

--

Alva Lan