netdev - [PATCH] cfg80211: fix locking in wiphy

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 26 Apr 2007 21:47:44 -0400
From:	"John W. Linville" <linville@...driver.com>
To:	davem@...emloft.net
Cc:	Johannes Berg <johannes@...solutions.net>, netdev@...r.kernel.org,
	linux-wireless@...r.kernel.org
Subject: [PATCH] cfg80211: fix locking in wiphy_new

From: Johannes Berg <johannes@...solutions.net>

This patch fixes the locking in wiphy new. Ingo Oeser <netdev@...eo.de>
noticed that locking in the error case was wrong and also suggested this
fix.

Signed-off-by: Johannes Berg <johannes@...solutions.net>
Signed-off-by: John W. Linville <linville@...driver.com>
---
 net/wireless/core.c |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 532e1e0..24a21ad 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -53,21 +53,25 @@ struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
 
 	mutex_lock(&cfg80211_drv_mutex);
 
-	if (unlikely(wiphy_counter<0)) {
+	drv->idx = wiphy_counter;
+
+	/* now increase counter for the next device unless
+	 * it has wrapped previously */
+	if (wiphy_counter >= 0)
+		wiphy_counter++;
+
+	mutex_unlock(&cfg80211_drv_mutex);
+
+	if (unlikely(drv->idx < 0)) {
 		/* ugh, wrapped! */
 		kfree(drv);
 		return NULL;
 	}
-	drv->idx = wiphy_counter;
 
 	/* give it a proper name */
 	snprintf(drv->wiphy.dev.bus_id, BUS_ID_SIZE,
 		 PHY_NAME "%d", drv->idx);
 
-	/* now increase counter for the next time */
-	wiphy_counter++;
-	mutex_unlock(&cfg80211_drv_mutex);
-
 	mutex_init(&drv->mtx);
 	mutex_init(&drv->devlist_mtx);
 	INIT_LIST_HEAD(&drv->netdev_list);
-- 
1.5.0.6

-- 
John W. Linville
linville@...driver.com
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html