watchdog: ts72xx_wdt: cleanup return codes in ioctl
There seems to be some confusion here which functions return positive
numbers and which return negative error codes.
copy_to_user() returns the number of bytes remaining to be copied but we
want to return -EFAULT.
The rest is just clean up. get_user() actually returns zero on success
and -EFAULT on error so we can preserve the error code. The
timeout_to_regval() function returns -EINVAL on failure, but we can
propogate that back instead of hardcoding -EINVAL ourselves.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
--
diff --git a/drivers/watchdog/ts72xx_wdt.c b/drivers/watchdog/ts72xx_wdt.c
index c9b0c62..df5dd55 100644
--- a/drivers/watchdog/ts72xx_wdt.c
+++ b/drivers/watchdog/ts72xx_wdt.c
@@ -305,7 +305,8 @@
switch (cmd) {
case WDIOC_GETSUPPORT:
- error = copy_to_user(argp, &winfo, sizeof(winfo));
+ if (copy_to_user(argp, &winfo, sizeof(winfo)))
+ error = -EFAULT;
break;
case WDIOC_GETSTATUS:
@@ -320,10 +321,9 @@
case WDIOC_SETOPTIONS: {
int options;
- if (get_user(options, p)) {
- error = -EFAULT;
+ error = get_user(options, p);
+ if (error)
break;
- }
error = -EINVAL;
@@ -341,30 +341,26 @@
case WDIOC_SETTIMEOUT: {
int new_timeout;
+ int regval;
- if (get_user(new_timeout, p)) {
- error = -EFAULT;
- } else {
- int regval;
-
- regval = timeout_to_regval(new_timeout);
- if (regval < 0) {
- error = -EINVAL;
- } else {
- ts72xx_wdt_stop(wdt);
- wdt->regval = regval;
- ts72xx_wdt_start(wdt);
- }
- }
+ error = get_user(new_timeout, p);
if (error)
break;
+ regval = timeout_to_regval(new_timeout);
+ if (regval < 0) {
+ error = regval;
+ break;
+ }
+ ts72xx_wdt_stop(wdt);
+ wdt->regval = regval;
+ ts72xx_wdt_start(wdt);
+
/*FALLTHROUGH*/
}
case WDIOC_GETTIMEOUT:
- if (put_user(regval_to_timeout(wdt->regval), p))
- error = -EFAULT;
+ error = put_user(regval_to_timeout(wdt->regval), p);
break;
default: