[S390] cio: Use strict_strtoul() for attributes.

Make parsing of attribute writes handle incorrect input better.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index c1afab5f72d6..595e327d2f76 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -705,13 +705,17 @@ css_cm_enable_store(struct device *dev, struct device_attribute *attr,
 {
         struct channel_subsystem *css = to_css(dev);
         int ret;
+        unsigned long val;
 
+        ret = strict_strtoul(buf, 16, &val);
+        if (ret)
+                return ret;
         mutex_lock(&css->mutex);
-        switch (buf[0]) {
-        case '0':
+        switch (val) {
+        case 0:
                 ret = css->cm_enabled ? chsc_secm(css, 0) : 0;
                 break;
-        case '1':
+        case 1:
                 ret = css->cm_enabled ? 0 : chsc_secm(css, 1);
                 break;
         default: