From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jan Beulich , Juergen Gross , Boris Ostrovsky , Sasha Levin Subject: [PATCH 4.4 29/40] xen/manage: correct return value check on xenbus_scanf() Date: Mon, 6 Nov 2017 10:45:04 +0100 Message-Id: <20171106094502.495178976@linuxfoundation.org> In-Reply-To: <20171106094501.346859822@linuxfoundation.org> References: <20171106094501.346859822@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Beulich [ Upstream commit 4fed1b125eb6252bde478665fc05d4819f774fa8 ] A negative return value indicates an error; in fact the function at present won't ever return zero. Signed-off-by: Jan Beulich Reviewed-by: Juergen Gross Signed-off-by: Boris Ostrovsky Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/xen/manage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -275,7 +275,7 @@ 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;