netdev - Re: [PULL 2/2] vhost: replace rcu with mutex

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]

Message-ID: <538DC422.1050303@redhat.com>
Date:	Tue, 03 Jun 2014 14:48:34 +0200
From:	Paolo Bonzini <pbonzini@...hat.com>
To:	Eric Dumazet <eric.dumazet@...il.com>,
	"Michael S. Tsirkin" <mst@...hat.com>
CC:	netdev@...r.kernel.org, virtualization@...ts.linux-foundation.org,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
	David Miller <davem@...emloft.net>
Subject: Re: [PULL 2/2] vhost: replace rcu with mutex

Il 02/06/2014 23:58, Eric Dumazet ha scritto:
> This looks dubious
>
> What about using kfree_rcu() instead ?

It would lead to unbound allocation from userspace.

> translate_desc() still uses rcu_read_lock(), its not clear if the mutex
> is really held.

Yes, vhost_get_vq_desc must be called with the vq mutex held.

The rcu_read_lock/unlock in translate_desc is unnecessary.

Paolo
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html