From: Jan Beulich <JBeulich@suse.com>
Date: Mon, 15 Aug 2016 15:02:38 +0000 (-0600)
Subject: xenbus: don't look up transaction IDs for ordinary writes
X-Git-Tag: firefly_0821_release~176^2~4^2~21^2~43
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=03cebefe8926d836d736e31d3f8259cd94e7814b;p=firefly-linux-kernel-4.4.55.git

xenbus: don't look up transaction IDs for ordinary writes

commit 9a035a40f7f3f6708b79224b86c5777a3334f7ea upstream.

This should really only be done for XS_TRANSACTION_END messages, or
else at least some of the xenstore-* tools don't work anymore.

Fixes: 0beef634b8 ("xenbus: don't BUG() on user mode induced condition")
Reported-by: Richard Schütz <rschuetz@uni-koblenz.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Richard Schütz <rschuetz@uni-koblenz.de>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: "M. Vefa Bicakci" <m.v.b@runbox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 531e76474983..0e0eb10f82a0 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -316,7 +316,7 @@ static int xenbus_write_transaction(unsigned msg_type,
 			rc = -ENOMEM;
 			goto out;
 		}
-	} else {
+	} else if (msg_type == XS_TRANSACTION_END) {
 		list_for_each_entry(trans, &u->transactions, list)
 			if (trans->handle.id == u->u.msg.tx_id)
 				break;