From: Michael Chan <mchan@broadcom.com>
Date: Sun, 29 Jul 2012 19:15:44 +0000 (+0000)
Subject: tg3: Fix race condition in tg3_get_stats64()
X-Git-Tag: v3.4.8~54
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=cbb9e89c375e167d012058c82fa69dd17ec17d4c;p=platform%2Fkernel%2Flinux-stable.git

tg3: Fix race condition in tg3_get_stats64()

commit 0f566b208b41918053b2e67399673aaec02dde5d upstream.

Spinlock should be taken before checking for tp->hw_stats.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 8506c54..689d2a1 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -12255,10 +12255,12 @@ static struct rtnl_link_stats64 *tg3_get_stats64(struct net_device *dev,
 {
 	struct tg3 *tp = netdev_priv(dev);
 
-	if (!tp->hw_stats)
+	spin_lock_bh(&tp->lock);
+	if (!tp->hw_stats) {
+		spin_unlock_bh(&tp->lock);
 		return &tp->net_stats_prev;
+	}
 
-	spin_lock_bh(&tp->lock);
 	tg3_get_nstats(tp, stats);
 	spin_unlock_bh(&tp->lock);