netdev - Re: [PATCH net-next v2] net: core: decouple ifalias get/set from rtnl lock

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: <20171002150936.GB30423@breakpoint.cc>
Date:   Mon, 2 Oct 2017 17:09:36 +0200
From:   Florian Westphal <fw@...len.de>
To:     Eric Dumazet <eric.dumazet@...il.com>
Cc:     Florian Westphal <fw@...len.de>, netdev@...r.kernel.org
Subject: Re: [PATCH net-next v2] net: core: decouple ifalias get/set from
 rtnl lock

Eric Dumazet <eric.dumazet@...il.com> wrote:
> Just use RCU : A writer is supposed to work on a private copy, and
> _then_ publish the new pointer, so that a reader can not see mangled
> string.
> 
> We either copy the 'old' name or the 'new' one.
> 
> A seqcount is not needed, and wont prevent you from reading the value
> right before a change anyway.

Would you rather use kfree_rcu or unconditional synchronize_net()
before releasing old memory?