Re: [PATCH] memfd: deny writeable mappings when implying SEAL_WRITE

[Pasha Tatashin]

On 05-05 15:37, Pasha Tatashin wrote:
> 
> On Tue, 05 May 2026 15:39:20 +0200, Pratyush Yadav wrote:
> > When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X. But the
> > implied seal is set after the check that makes sure the memfd can not
> > have any writable mappings. This means one can use SEAL_EXEC to apply
> > SEAL_WRITE while having writeable mappings.
> > 
> > This breaks the contract that SEAL_WRITE provides and can be used by an
> > attacker to pass a memfd that appears to be write sealed but can still
> > be modified arbitrarily.
> > 
> > [...]
> 
> Applied, thanks!
> 
> [1/1] memfd: deny writeable mappings when implying SEAL_WRITE
>       commit: 73f496662a9848021e75742a69a3239ea850c3ee

^^^
Please ignore, this should be Applied to MM tree.

Pasha

> 
> Best regards,
> -- 
> Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
>