netdev - Re: [PATCH net] net: bpfilter: use get_pid_task instead of pid

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]

Date:   Wed, 17 Oct 2018 22:04:39 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     ap420073@...il.com
Cc:     netdev@...r.kernel.org, daniel@...earbox.net, ast@...nel.org
Subject: Re: [PATCH net] net: bpfilter: use get_pid_task instead of pid_task

From: Taehee Yoo <ap420073@...il.com>
Date: Wed, 17 Oct 2018 00:35:10 +0900

> pid_task() dereferences rcu protected tasks array.
> But there is no rcu_read_lock() in shutdown_umh() routine so that
> rcu_read_lock() is needed.
> get_pid_task() is wrapper function of pid_task. it holds rcu_read_lock()
> then calls pid_task(). if task isn't NULL, it increases reference count
> of task.
> 
> test commands:
>    %modprobe bpfilter
>    %modprobe -rv bpfilter
 ...
> Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")
> Signed-off-by: Taehee Yoo <ap420073@...il.com>

Applied and queued up for -stable, thanks.