From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:40412 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163592AbeE1Kuz (ORCPT ); Mon, 28 May 2018 06:50:55 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Igor Pylypiv , Guenter Roeck , Wim Van Sebroeck , Sasha Levin Subject: [PATCH 4.14 209/496] watchdog: f71808e_wdt: Fix magic close handling Date: Mon, 28 May 2018 11:59:54 +0200 Message-Id: <20180528100328.739683452@linuxfoundation.org> In-Reply-To: <20180528100319.498712256@linuxfoundation.org> References: <20180528100319.498712256@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Igor Pylypiv [ Upstream commit 7bd3e7b743956afbec30fb525bc3c5e22e3d475c ] Watchdog close is "expected" when any byte is 'V' not just the last one. Writing "V" to the device fails because the last byte is the end of string. $ echo V > /dev/watchdog f71808e_wdt: Unexpected close, not stopping watchdog! Signed-off-by: Igor Pylypiv Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/watchdog/f71808e_wdt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/watchdog/f71808e_wdt.c +++ b/drivers/watchdog/f71808e_wdt.c @@ -566,7 +566,8 @@ static ssize_t watchdog_write(struct fil char c; if (get_user(c, buf + i)) return -EFAULT; - expect_close = (c == 'V'); + if (c == 'V') + expect_close = true; } /* Properly order writes across fork()ed processes */