Patch "netfilter: nf_log: don't zap all loggers on unregister" has been added to the 4.2-stable tree

[<gregkh@linuxfoundation.org>]

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

    netfilter: nf_log: don't zap all loggers on unregister

to the 4.2-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-nf_log-don-t-zap-all-loggers-on-unregister.patch
and it can be found in the queue-4.2 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 205ee117d4dc4a11ac3bd9638bb9b2e839f4de9a Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Wed, 9 Sep 2015 02:57:21 +0200
Subject: netfilter: nf_log: don't zap all loggers on unregister

From: Florian Westphal <fw@strlen.de>

commit 205ee117d4dc4a11ac3bd9638bb9b2e839f4de9a upstream.

like nf_log_unset, nf_log_unregister must not reset the list of loggers.
Otherwise, a call to nf_log_unregister() will render loggers of other nf
protocols unusable:

iptables -A INPUT -j LOG
modprobe nf_log_arp ; rmmod nf_log_arp
iptables -A INPUT -j LOG
iptables: No chain/target/match by that name

Fixes: 30e0c6a6be ("netfilter: nf_log: prepare net namespace support for loggers")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/netfilter/nf_log.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -107,11 +107,15 @@ EXPORT_SYMBOL(nf_log_register);
 
 void nf_log_unregister(struct nf_logger *logger)
 {
+	const struct nf_logger *log;
 	int i;
 
 	mutex_lock(&nf_log_mutex);
-	for (i = 0; i < NFPROTO_NUMPROTO; i++)
-		RCU_INIT_POINTER(loggers[i][logger->type], NULL);
+	for (i = 0; i < NFPROTO_NUMPROTO; i++) {
+		log = nft_log_dereference(loggers[i][logger->type]);
+		if (log == logger)
+			RCU_INIT_POINTER(loggers[i][logger->type], NULL);
+	}
 	mutex_unlock(&nf_log_mutex);
 	synchronize_rcu();
 }


Patches currently in stable-queue which might be from fw@strlen.de are

queue-4.2/netfilter-nfnetlink-work-around-wrong-endianess-in-res_id-field.patch
queue-4.2/netfilter-nf_log-don-t-zap-all-loggers-on-unregister.patch