netdev - Re: [PATCH] rxrpc: Call state should be read with READ

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: <773322.1610017548@warthog.procyon.org.uk>
Date:   Thu, 07 Jan 2021 11:05:48 +0000
From:   David Howells <dhowells@...hat.com>
To:     Baptiste Lepers <baptiste.lepers@...il.com>
Cc:     dhowells@...hat.com, davem@...emloft.net, kuba@...nel.org,
        linux-afs@...ts.infradead.org, netdev@...r.kernel.org
Subject: Re: [PATCH] rxrpc: Call state should be read with READ_ONCE() under some circumstances

Baptiste Lepers <baptiste.lepers@...il.com> wrote:

> The call state may be changed at any time by the data-ready routine in
> response to received packets, so if the call state is to be read and acted
> upon several times in a function, READ_ONCE() must be used unless the call
> state lock is held.

I'm going to add:

    As it happens, we used READ_ONCE() to read the state a few lines above the
    unmarked read in rxrpc_input_data(), so use that value rather than
    re-reading it.

to the commit message, if that's okay by you.

David