Patch "xen/manage: correct return value check on xenbus_scanf()" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

xen/manage: correct return value check on xenbus_scanf()

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
xen-manage-correct-return-value-check-on-xenbus_scanf.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jan Beulich <[email protected]>
Date: Sat, 7 Oct 2017 22:36:53 +0000
Subject: xen/manage: correct return value check on xenbus_scanf()

From: Jan Beulich <[email protected]>

[ Upstream commit 4fed1b125eb6252bde478665fc05d4819f774fa8 ]

A negative return value indicates an error; in fact the function at present won't ever return zero.

---
 drivers/xen/manage.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -277,7 +277,7 @@ static void sysrq_handler(struct xenbus_
 	err = xenbus_transaction_start(&xbt);
 	if (err)
 		return;
-	if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) {
+	if (xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key) < 0) {
 		pr_err("Unable to read sysrq code in control/sysrq\n");
 		xenbus_transaction_end(xbt, 1);
 		return;

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/xen-manage-correct-return-value-check-on-xenbus_scanf.patch