netdev - Re: [patch net] net/mlx5: DPLL, Fix possible use after free after delayed work timer triggers

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: Thu, 8 Feb 2024 15:05:50 +0000
From: Simon Horman <horms@...nel.org>
To: Jiri Pirko <jiri@...nulli.us>
Cc: netdev@...r.kernel.org, vadim.fedorenko@...ux.dev,
	arkadiusz.kubalewski@...el.com, saeedm@...dia.com, leon@...nel.org,
	davem@...emloft.net, edumazet@...gle.com, kuba@...nel.org,
	pabeni@...hat.com
Subject: Re: [patch net] net/mlx5: DPLL, Fix possible use after free after
 delayed work timer triggers

On Tue, Feb 06, 2024 at 05:43:28PM +0100, Jiri Pirko wrote:
> From: Jiri Pirko <jiri@...dia.com>
> 
> I managed to hit following use after free warning recently:

...

> I didn't manage to reproduce it. Though the issue seems to be obvious.
> There is a chance that the mlx5_dpll_remove() calls
> cancel_delayed_work() when the work runs and manages to re-arm itself.
> In that case, after delay timer triggers next attempt to queue it,
> it works with freed memory.
> 
> Fix this by using cancel_delayed_work_sync() instead which makes sure
> that work is done when it returns.
> 
> Fixes: 496fd0a26bbf ("mlx5: Implement SyncE support using DPLL infrastructure")
> Signed-off-by: Jiri Pirko <jiri@...dia.com>

Reviewed-by: Simon Horman <horms@...nel.org>