From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:49630 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753106AbeBFUsv (ORCPT ); Tue, 6 Feb 2018 15:48:51 -0500 Subject: Patch "cls_u32: add missing RCU annotation." has been added to the 4.9-stable tree To: pabeni@redhat.com, davem@davemloft.net, gregkh@linuxfoundation.org, xiyou.wangcong@gmail.com Cc: , From: Date: Tue, 06 Feb 2018 12:48:49 -0800 Message-ID: <15179501298141@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 cls_u32: add missing RCU annotation. to the 4.9-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: cls_u32-add-missing-rcu-annotation.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Tue Feb 6 12:42:23 PST 2018 From: Paolo Abeni Date: Fri, 2 Feb 2018 16:02:22 +0100 Subject: cls_u32: add missing RCU annotation. From: Paolo Abeni [ Upstream commit 058a6c033488494a6b1477b05fe8e1a16e344462 ] In a couple of points of the control path, n->ht_down is currently accessed without the required RCU annotation. The accesses are safe, but sparse complaints. Since we already held the rtnl lock, let use rtnl_dereference(). Fixes: a1b7c5fd7fe9 ("net: sched: add cls_u32 offload hooks for netdevs") Fixes: de5df63228fc ("net: sched: cls_u32 changes to knode must appear atomic to readers") Signed-off-by: Paolo Abeni Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/cls_u32.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -496,6 +496,7 @@ static void u32_clear_hw_hnode(struct tc static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n, u32 flags) { + struct tc_u_hnode *ht = rtnl_dereference(n->ht_down); struct net_device *dev = tp->q->dev_queue->dev; struct tc_cls_u32_offload u32_offload = {0}; struct tc_to_netdev offload; @@ -520,7 +521,7 @@ static int u32_replace_hw_knode(struct t offload.cls_u32->knode.sel = &n->sel; offload.cls_u32->knode.exts = &n->exts; if (n->ht_down) - offload.cls_u32->knode.link_handle = n->ht_down->handle; + offload.cls_u32->knode.link_handle = ht->handle; err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol, &offload); @@ -788,8 +789,9 @@ static void u32_replace_knode(struct tcf static struct tc_u_knode *u32_init_knode(struct tcf_proto *tp, struct tc_u_knode *n) { - struct tc_u_knode *new; + struct tc_u_hnode *ht = rtnl_dereference(n->ht_down); struct tc_u32_sel *s = &n->sel; + struct tc_u_knode *new; new = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL); @@ -807,11 +809,11 @@ static struct tc_u_knode *u32_init_knode new->fshift = n->fshift; new->res = n->res; new->flags = n->flags; - RCU_INIT_POINTER(new->ht_down, n->ht_down); + RCU_INIT_POINTER(new->ht_down, ht); /* bump reference count as long as we hold pointer to structure */ - if (new->ht_down) - new->ht_down->refcnt++; + if (ht) + ht->refcnt++; #ifdef CONFIG_CLS_U32_PERF /* Statistics may be incremented by readers during update Patches currently in stable-queue which might be from pabeni@redhat.com are queue-4.9/cls_u32-add-missing-rcu-annotation.patch