Patch "netfilter: nft_queue: use raw_smp_processor_id()" has been added to the 4.4-stable tree

Patch "netfilter: nft_queue: use raw_smp_processor_id()" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    netfilter: nft_queue: use raw_smp_processor_id()

to the 4.4-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:
     netfilter-nft_queue-use-raw_smp_processor_id.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Tue Nov 28 10:56:34 CET 2017
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Sun, 11 Dec 2016 20:46:51 +0100
Subject: netfilter: nft_queue: use raw_smp_processor_id()

From: Pablo Neira Ayuso <pablo@netfilter.org>


[ Upstream commit c2e756ff9e699865d294cdc112acfc36419cf5cc ]

Using smp_processor_id() causes splats with PREEMPT_RCU:

[19379.552780] BUG: using smp_processor_id() in preemptible [00000000] code: ping/32389
[19379.552793] caller is debug_smp_processor_id+0x17/0x19
[...]
[19379.552823] Call Trace:
[19379.552832]  [<ffffffff81274e9e>] dump_stack+0x67/0x90
[19379.552837]  [<ffffffff8129a4d4>] check_preemption_disabled+0xe5/0xf5
[19379.552842]  [<ffffffff8129a4fb>] debug_smp_processor_id+0x17/0x19
[19379.552849]  [<ffffffffa07c42dd>] nft_queue_eval+0x35/0x20c [nft_queue]

No need to disable preemption since we only fetch the numeric value, so
let's use raw_smp_processor_id() instead.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/netfilter/nft_queue.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/netfilter/nft_queue.c
+++ b/net/netfilter/nft_queue.c
@@ -37,7 +37,7 @@ static void nft_queue_eval(const struct
 
 	if (priv->queues_total > 1) {
 		if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT) {
-			int cpu = smp_processor_id();
+			int cpu = raw_smp_processor_id();
 
 			queue = priv->queuenum + cpu % priv->queues_total;
 		} else {


Patches currently in stable-queue which might be from pablo@netfilter.org are

queue-4.4/netfilter-nf_tables-fix-oob-access.patch
queue-4.4/netfilter-nft_queue-use-raw_smp_processor_id.patch