netdev - [PATCH 1/3] batman-adv: wait for rtnl in batadv_store_mesh

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

Message-Id: <1370932501-3937-2-git-send-email-ordex@autistici.org>
Date:	Tue, 11 Jun 2013 08:34:59 +0200
From:	Antonio Quartulli <ordex@...istici.org>
To:	davem@...emloft.net
Cc:	netdev@...r.kernel.org, b.a.t.m.a.n@...ts.open-mesh.org,
	Matthias Schiffer <mschiffer@...verse-factory.net>,
	Marek Lindner <lindner_marek@...oo.de>,
	Antonio Quartulli <ordex@...istici.org>
Subject: [PATCH 1/3] batman-adv: wait for rtnl in batadv_store_mesh_iface instead of failing if it is taken

From: Matthias Schiffer <mschiffer@...verse-factory.net>

The rtnl_lock in batadv_store_mesh_iface has been converted to a rtnl_trylock
some time ago to avoid a possible deadlock between rtnl and s_active on removal
of the sysfs nodes.

The behaviour introduced by that was quite confusing as it could lead to the
sysfs store to fail, making batman-adv setup scripts unreliable. As recently the
sysfs removal was postponed to a worker not running with the rtnl taken, the
deadlock can't occur any more and it is safe to change the trylock back to a
lock to make the sysfs store reliable again.

Signed-off-by: Matthias Schiffer <mschiffer@...verse-factory.net>
Reviewed-by: Simon Wunderlich <siwu@....tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@...oo.de>
Signed-off-by: Antonio Quartulli <ordex@...istici.org>
---
 net/batman-adv/sysfs.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c
index 15a22ef..929e304 100644
--- a/net/batman-adv/sysfs.c
+++ b/net/batman-adv/sysfs.c
@@ -582,10 +582,7 @@ static ssize_t batadv_store_mesh_iface(struct kobject *kobj,
 	    (strncmp(hard_iface->soft_iface->name, buff, IFNAMSIZ) == 0))
 		goto out;
 
-	if (!rtnl_trylock()) {
-		ret = -ERESTARTSYS;
-		goto out;
-	}
+	rtnl_lock();
 
 	if (status_tmp == BATADV_IF_NOT_IN_USE) {
 		batadv_hardif_disable_interface(hard_iface,
-- 
1.8.1.5

--
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