linux-kernel - Re: [PATCH v2 1/3] Fix userfaultfd_api to return EINVAL as expected

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Fri, 21 Jun 2024 17:25:54 -0400
From: Peter Xu <peterx@...hat.com>
To: Audra Mitchell <audra@...hat.com>
Cc: viro@...iv.linux.org.uk, brauner@...nel.org, jack@...e.cz,
	aarcange@...hat.com, akpm@...ux-foundation.org,
	rppt@...ux.vnet.ibm.com, shli@...com, linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org, shuah@...nel.org,
	linux-kselftest@...r.kernel.org, raquini@...hat.com
Subject: Re: [PATCH v2 1/3] Fix userfaultfd_api to return EINVAL as expected

On Fri, Jun 21, 2024 at 02:12:22PM -0400, Audra Mitchell wrote:
> Currently if we request a feature that is not set in the Kernel
> config we fail silently and return all the available features. However,
> the man page indicates we should return an EINVAL.
> 
> We need to fix this issue since we can end up with a Kernel warning
> should a program request the feature UFFD_FEATURE_WP_UNPOPULATED on
> a kernel with the config not set with this feature.
> 
>  [  200.812896] WARNING: CPU: 91 PID: 13634 at mm/memory.c:1660 zap_pte_range+0x43d/0x660
>  [  200.820738] Modules linked in:
>  [  200.869387] CPU: 91 PID: 13634 Comm: userfaultfd Kdump: loaded Not tainted 6.9.0-rc5+ #8
>  [  200.877477] Hardware name: Dell Inc. PowerEdge R6525/0N7YGH, BIOS 2.7.3 03/30/2022
>  [  200.885052] RIP: 0010:zap_pte_range+0x43d/0x660
> 
> Fixes: e06f1e1dd499 ("userfaultfd: wp: enabled write protection in userfaultfd API")
> Signed-off-by: Audra Mitchell <audra@...hat.com>

Please prefix the subject with "mm/uffd:" or "mm/userfault:" if there's a
repost.

Acked-by: Peter Xu <peterx@...hat.com>

Thanks,

-- 
Peter Xu