From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:39224 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751917AbdC0QTm (ORCPT ); Mon, 27 Mar 2017 12:19:42 -0400 Subject: Patch "genetlink: fix counting regression on ctrl_dumpfamily()" has been added to the 4.10-stable tree To: sgruszka@redhat.com, Larry.Finger@lwfinger.net, davem@davemloft.net, gregkh@linuxfoundation.org, johannes@sipsolutions.net, xose.vazquez@gmail.com Cc: , From: Date: Mon, 27 Mar 2017 18:19:21 +0200 Message-ID: <14906315616999@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled genetlink: fix counting regression on ctrl_dumpfamily() to the 4.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: genetlink-fix-counting-regression-on-ctrl_dumpfamily.patch and it can be found in the queue-4.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Mon Mar 27 18:18:08 CEST 2017 From: Stanislaw Gruszka Date: Wed, 22 Mar 2017 16:08:33 +0100 Subject: genetlink: fix counting regression on ctrl_dumpfamily() From: Stanislaw Gruszka [ Upstream commit 1d2a6a5e4bf2921531071fcff8538623dce74efa ] Commit 2ae0f17df1cd ("genetlink: use idr to track families") replaced if (++n < fams_to_skip) continue; into: if (n++ < fams_to_skip) continue; This subtle change cause that on retry ctrl_dumpfamily() call we omit one family that failed to do ctrl_fill_info() on previous call, because cb->args[0] = n number counts also family that failed to do ctrl_fill_info(). Patch fixes the problem and avoid confusion in the future just decrease n counter when ctrl_fill_info() fail. User visible problem caused by this bug is failure to get access to some genetlink family i.e. nl80211. However problem is reproducible only if number of registered genetlink families is big enough to cause second call of ctrl_dumpfamily(). Cc: Xose Vazquez Perez Cc: Larry Finger Cc: Johannes Berg Fixes: 2ae0f17df1cd ("genetlink: use idr to track families") Signed-off-by: Stanislaw Gruszka Acked-by: Johannes Berg Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/netlink/genetlink.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -783,8 +783,10 @@ static int ctrl_dumpfamily(struct sk_buf if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, - skb, CTRL_CMD_NEWFAMILY) < 0) + skb, CTRL_CMD_NEWFAMILY) < 0) { + n--; break; + } } cb->args[0] = n; Patches currently in stable-queue which might be from sgruszka@redhat.com are queue-4.10/genetlink-fix-counting-regression-on-ctrl_dumpfamily.patch