From 7bd3e7b743956afbec30fb525bc3c5e22e3d475c Mon Sep 17 00:00:00 2001
From: Igor Pylypiv <igor.pylypiv@gmail.com>
Date: Wed, 28 Feb 2018 00:59:12 -0800
Subject: [PATCH] watchdog: f71808e_wdt: Fix magic close handling
Git-commit: 7bd3e7b743956afbec30fb525bc3c5e22e3d475c
Patch-mainline: v4.16-rc5
References: bsc#1051510
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 <igor.pylypiv@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/watchdog/f71808e_wdt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/f71808e_wdt.c b/drivers/watchdog/f71808e_wdt.c
index e0678c14480f..3a33c5344bd5 100644
--- a/drivers/watchdog/f71808e_wdt.c
+++ b/drivers/watchdog/f71808e_wdt.c
@@ -566,7 +566,8 @@ static ssize_t watchdog_write(struct file *file, const char __user *buf,
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 */
--
2.18.0