linux-kernel - Re: [PATCH v5] workqueue: Remove unnecessary kfree() call in rcu_free

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] [day] [month] [year] [list]

Message-ID: <20200527135214.GI83516@mtj.thefacebook.com>
Date:   Wed, 27 May 2020 09:52:14 -0400
From:   Tejun Heo <tj@...nel.org>
To:     qiang.zhang@...driver.com
Cc:     jiangshanlai@...il.com, markus.elfring@....de,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v5] workqueue: Remove unnecessary kfree() call in
 rcu_free_wq()

On Wed, May 27, 2020 at 03:57:15PM +0800, qiang.zhang@...driver.com wrote:
> From: Zhang Qiang <qiang.zhang@...driver.com>
> 
> The data structure member "wq->rescuer" was reset to a null pointer
> in one if branch. It was passed to a call of the function "kfree"
> in the callback function "rcu_free_wq" (which was eventually executed).
> The function "kfree" does not perform more meaningful data processing
> for a passed null pointer (besides immediately returning from such a call).
> Thus delete this function call which became unnecessary with the referenced
> software update.
> 
> Fixes: def98c84b6cd ("workqueue: Fix spurious sanity check failures in destroy_workqueue()")
> 
> Suggested-by: Markus Elfring <Markus.Elfring@....de> 
> Signed-off-by: Zhang Qiang <qiang.zhang@...driver.com>

Applied to wq/for-5.8.

Thanks.

-- 
tejun