NFC: Fix error handling in nfc_genl_dump_targets

nfc_genl_dump_targets() increments the device reference count via
nfc_get_device() but fails to decrement it properly. nfc_get_device()
calls class_find_device() which internally calls get_device() to
increment the reference count. No corresponding put_device() is made
to decrement the reference count.

Add proper reference count decrementing using nfc_put_device() when
the dump operation completes or encounters an error, ensuring balanced
reference counting.

Found by code review.

Cc: stable@vger.kernel.org
Fixes: 4d12b8b ("NFC: add nfc generic netlink interface")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: NipaLocal <nipa@local>

Author: Ma Ke

net/nfc/netlink.c

@@ -159,6 +159,11 @@ static int nfc_genl_dump_targets(struct sk_buff *skb,
 
 	cb->args[0] = i;
 
+	if (rc < 0 || i >= dev->n_targets) {
+		nfc_put_device(dev);
+		cb->args[1] = 0;
+	}
+
 	return skb->len;
 }