netdev - Re: [PATCH net] netfilter: nf_log: don't hold nf_log

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: <20180626160515.erczjbfvhauqlyfe@salvia>
Date:   Tue, 26 Jun 2018 18:05:15 +0200
From:   Pablo Neira Ayuso <pablo@...filter.org>
To:     Jann Horn <jannh@...gle.com>
Cc:     Jozsef Kadlecsik <kadlec@...ckhole.kfki.hu>,
        Florian Westphal <fw@...len.de>,
        "David S. Miller" <davem@...emloft.net>,
        netfilter-devel@...r.kernel.org, coreteam@...filter.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        security@...nel.org
Subject: Re: [PATCH net] netfilter: nf_log: don't hold nf_log_mutex during
 user access

On Mon, Jun 25, 2018 at 05:22:00PM +0200, Jann Horn wrote:
> The old code would indefinitely block other users of nf_log_mutex if
> a userspace access in proc_dostring() blocked e.g. due to a userfaultfd
> region. Fix it by moving proc_dostring() out of the locked region.
> 
> This is a followup to commit 266d07cb1c9a ("netfilter: nf_log: fix
> sleeping function called from invalid context"), which changed this code
> from using rcu_read_lock() to taking nf_log_mutex.

Applied.