linux-kernel - [ 042/171] SUNRPC: Fix validity issues with rpc_pipefs sb->s_fs

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: <20130115224316.455938534@linuxfoundation.org>
Date:	Tue, 15 Jan 2013 14:43:27 -0800
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	alan@...rguk.ukuu.org.uk,
	Trond Myklebust <Trond.Myklebust@...app.com>,
	Stanislav Kinsbursky <skinsbursky@...allels.com>
Subject: [ 042/171] SUNRPC: Fix validity issues with rpc_pipefs sb->s_fs_info

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Trond Myklebust <Trond.Myklebust@...app.com>

commit 642fe4d00db56d65060ce2fd4c105884414acb16 upstream.

rpc_kill_sb() must defer calling put_net() until after the notifier
has been called, since most (all?) of the notifier callbacks assume
that sb->s_fs_info points to a valid net namespace. It also must not
call put_net() if the call to rpc_fill_super was unsuccessful.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=48421

Signed-off-by: Trond Myklebust <Trond.Myklebust@...app.com>
Cc: Stanislav Kinsbursky <skinsbursky@...allels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 net/sunrpc/rpc_pipe.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -1157,14 +1157,19 @@ static void rpc_kill_sb(struct super_blo
 	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 
 	mutex_lock(&sn->pipefs_sb_lock);
+	if (sn->pipefs_sb != sb) {
+		mutex_unlock(&sn->pipefs_sb_lock);
+		goto out;
+	}
 	sn->pipefs_sb = NULL;
 	mutex_unlock(&sn->pipefs_sb_lock);
-	put_net(net);
 	dprintk("RPC:	sending pipefs UMOUNT notification for net %p%s\n", net,
 								NET_NAME(net));
 	blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
 					   RPC_PIPEFS_UMOUNT,
 					   sb);
+	put_net(net);
+out:
 	kill_litter_super(sb);
 }
 


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/