From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [net PATCH v2 2/2] net: netprio: fd passed in SCM_RIGHTS datagram not set correctly Date: Tue, 14 Aug 2012 07:35:52 -0700 Message-ID: <502A6248.6090709@intel.com> References: <20120814024320.6983.92222.stgit@jf-dev1-dcblab> <20120814024326.6983.97403.stgit@jf-dev1-dcblab> <20120814125523.GA18731@hmsreliant.think-freely.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: viro@ZenIV.linux.org.uk, netdev@vger.kernel.org, davem@davemloft.net, linux-kernel@vger.kernel.org, joe@perches.com To: Neil Horman Return-path: In-Reply-To: <20120814125523.GA18731@hmsreliant.think-freely.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 8/14/2012 5:55 AM, Neil Horman wrote: > On Mon, Aug 13, 2012 at 07:43:27PM -0700, John Fastabend wrote: >> A socket fd passed in a SCM_RIGHTS datagram was not getting >> updated with the new tasks cgrp prioidx. This leaves IO on >> the socket tagged with the old tasks priority. >> >> To fix this add a check in the scm recvmsg path to update the >> sock cgrp prioidx with the new tasks value. >> >> Thanks to Al Viro for catching this. >> >> CC: Neil Horman >> Reported-by: Al Viro >> Signed-off-by: John Fastabend >> --- >> [...] >> @@ -281,6 +283,9 @@ void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm) >> } >> /* Bump the usage count and install the file. */ >> get_file(fp[i]); >> + sock = sock_from_file(fp[i], &err); >> + if (sock) >> + sock->sk->sk_cgrp_prioidx = prioidx; > nit: You can replace the prioidx variable above and this set with a call to > sock_update_netprioidx > > Neil > OK but then I should also make sock_update_netprioidx inline and drop the in_interrupt() call. I'll send a v3 with this change and also a third patch to fix a race between write_priomap and cgrp_create (also spotted by Al Viro).