[patch] bluetooth: debugfs changes use too much stack

[Dan Carpenter <error27@gmail.com>]

The original code would break with a 4K stack.

Signed-off-by: Dan Carpenter <error27@gmail.com>
---
This was compile tested only.  Sorry about that.

diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index 1a79a6c..835758f 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/net/bluetooth/hci_sysfs.c
@@ -417,9 +417,11 @@ static ssize_t inquiry_cache_read(struct file *file, char __user *userbuf,
 	struct hci_dev *hdev = file->private_data;
 	struct inquiry_cache *cache = &hdev->inq_cache;
 	struct inquiry_entry *e;
-	char buf[4096];
+	char *buf;
 	int n = 0;
+	ssize_t ret;
 
+	buf = kmalloc(4096, GFP_KERNEL);
 	hci_dev_lock_bh(hdev);
 
 	for (e = cache->list; e; e = e->next) {
@@ -437,7 +439,10 @@ static ssize_t inquiry_cache_read(struct file *file, char __user *userbuf,
 
 	hci_dev_unlock_bh(hdev);
 
-	return simple_read_from_buffer(userbuf, count, ppos, buf, n);
+	ret = simple_read_from_buffer(userbuf, count, ppos, buf, n);
+	kfree(buf);
+
+	return ret;
 }
 
 static const struct file_operations inquiry_cache_fops = {