From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [192.168.1.190] ([192.168.1.190]) by arianne.in.ishoni.com (8.11.6/Ishonir2) with ESMTP id gBLCxvt32265 for ; Sat, 21 Dec 2002 18:29:59 +0530 Subject: copy_from_user From: Amol Kumar Lad Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: 21 Dec 2002 18:26:30 -0500 Message-Id: <1040513191.2250.79.camel@amol.in.ishoni.com> Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm@kvack.org List-ID: Hi, Suppose kernel tries to do copy_from_user from a pointer that does not have any mapping. i.e. not in any VMA (and not in stack area too..). Now (for 1386) access_ok --> __range_ok Suppose the 'from' ptr is within range then how kernel is making sure that 'from' is invalid ?? The page fault handler will see that 'from' has no mapping and it will die.. Please help Amol -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/