rfkill: allow toggling soft state in sysfs again

Apparently there actually _are_ tools that try to set
this in sysfs even though it wasn't supposed to be used
this way without claiming first. Guess what: now that
I've cleaned it all up it doesn't matter and we can
simply allow setting the soft-block state in sysfs.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Tested-By: Darren Salt <linux@youmustbejoking.demon.co.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 19 insertions, 8 deletions

diff --git a/net/rfkill/core.c b/net/rfkill/core.c
index 79693fe2001e..6896c0b45b4a 100644
--- a/net/rfkill/core.c
+++ b/net/rfkill/core.c
@@ -648,15 +648,26 @@ static ssize_t rfkill_state_store(struct device *dev,
                                   struct device_attribute *attr,
                                   const char *buf, size_t count)
 {
-        /*
-         * The intention was that userspace can only take control over
-         * a given device when/if rfkill-input doesn't control it due
-         * to user_claim. Since user_claim is currently unsupported,
-         * we never support changing the state from userspace -- this
-         * can be implemented again later.
-         */
+        struct rfkill *rfkill = to_rfkill(dev);
+        unsigned long state;
+        int err;
+
+        if (!capable(CAP_NET_ADMIN))
+                return -EPERM;
+
+        err = strict_strtoul(buf, 0, &state);
+        if (err)
+                return err;
+
+        if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
+            state != RFKILL_USER_STATE_UNBLOCKED)
+                return -EINVAL;
+
+        mutex_lock(&rfkill_global_mutex);
+        rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
+        mutex_unlock(&rfkill_global_mutex);
 
-        return -EPERM;
+        return err ?: count;
 }
 
 static ssize_t rfkill_claim_show(struct device *dev,