4.9-stable review patch. If anyone has any objections, please let me know.
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From: Igor Pylypiv igor.pylypiv@gmail.com
[ 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 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 Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 */