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

    genl: Fix genl dumpit() locking.

to the 3.10-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:
     genl-fix-genl-dumpit-locking.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 0b91de5d552a5c8adbcc071aebe8dbccfc0d4cda Mon Sep 17 00:00:00 2001
From: Pravin B Shelar <[email protected]>
Date: Fri, 23 Aug 2013 12:44:55 -0700
Subject: genl: Fix genl dumpit() locking.

From: Pravin B Shelar <[email protected]>

[ Upstream commit 9b96309c5b0b9e466773c07a5bc8b7b68fcf010a ]

In case of genl-family with parallel ops off, dumpif() callback
is expected to run under genl_lock, But commit def3117493eafd9df
(genl: Allow concurrent genl callbacks.) changed this behaviour
where only first dumpit() op was called under genl-lock.
For subsequent dump, only nlk->cb_lock was taken.
Following patch fixes it by defining locked dumpit() and done()
callback which takes care of genl-locking.

Signed-off-by: Pravin B Shelar <[email protected]>
CC: Jesse Gross <[email protected]>
CC: Johannes Berg <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 net/netlink/genetlink.c |   51 +++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 46 insertions(+), 5 deletions(-)

--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -544,6 +544,30 @@ void *genlmsg_put(struct sk_buff *skb, u
 }
 EXPORT_SYMBOL(genlmsg_put);
 
+static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
+{
+       struct genl_ops *ops = cb->data;
+       int rc;
+
+       genl_lock();
+       rc = ops->dumpit(skb, cb);
+       genl_unlock();
+       return rc;
+}
+
+static int genl_lock_done(struct netlink_callback *cb)
+{
+       struct genl_ops *ops = cb->data;
+       int rc = 0;
+
+       if (ops->done) {
+               genl_lock();
+               rc = ops->done(cb);
+               genl_unlock();
+       }
+       return rc;
+}
+
 static int genl_family_rcv_msg(struct genl_family *family,
                               struct sk_buff *skb,
                               struct nlmsghdr *nlh)
@@ -572,15 +596,32 @@ static int genl_family_rcv_msg(struct ge
                return -EPERM;
 
        if (nlh->nlmsg_flags & NLM_F_DUMP) {
-               struct netlink_dump_control c = {
-                       .dump = ops->dumpit,
-                       .done = ops->done,
-               };
+               int rc;
 
                if (ops->dumpit == NULL)
                        return -EOPNOTSUPP;
 
-               return netlink_dump_start(net->genl_sock, skb, nlh, &c);
+               if (!family->parallel_ops) {
+                       struct netlink_dump_control c = {
+                               .data = ops,
+                               .dump = genl_lock_dumpit,
+                               .done = genl_lock_done,
+                       };
+
+                       genl_unlock();
+                       rc = netlink_dump_start(net->genl_sock, skb, nlh, &c);
+                       genl_lock();
+
+               } else {
+                       struct netlink_dump_control c = {
+                               .dump = ops->dumpit,
+                               .done = ops->done,
+                       };
+
+                       rc = netlink_dump_start(net->genl_sock, skb, nlh, &c);
+               }
+
+               return rc;
        }
 
        if (ops->doit == NULL)


Patches currently in stable-queue which might be from [email protected] are

queue-3.10/genl-hold-reference-on-correct-module-while-netlink-dump.patch
queue-3.10/ip_gre-fix-ipgre_header-to-return-correct-offset-mime-version-1.0.patch
queue-3.10/genl-fix-genl-dumpit-locking.patch
queue-3.10/ip_tunnel-do-not-use-inner-ip-header-id-for-tunnel-ip-header-id.patch
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