PARISC: led.c - fix potential stack overflow in led_proc_write()

avoid potential stack overflow by correctly checking count parameter

Reported-by: Ilja <[e-mail]>
Signed-off-by: Helge Deller <[e-mail]>
Acked-by: Kyle McMartin <[e-mail]>
Cc: James E.J. Bottomley <[e-mail]>
Cc: [e-mail]
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/parisc/led.c

···
 	size_t count, loff_t *pos)
 {
 	void *data = PDE(file->f_path.dentry->d_inode)->data;
-	char *cur, lbuf[count + 1];
+	char *cur, lbuf[32];
 	int d;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	memset(lbuf, 0, count + 1);
+	if (count >= sizeof(lbuf))
+		count = sizeof(lbuf)-1;
 
 	if (copy_from_user(lbuf, buf, count))
 		return -EFAULT;
+	lbuf[count] = 0;
 
 	cur = lbuf;