Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261583AbVCGARQ (ORCPT ); Sun, 6 Mar 2005 19:17:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261556AbVCGARQ (ORCPT ); Sun, 6 Mar 2005 19:17:16 -0500 Received: from mail.dif.dk ([193.138.115.101]:691 "EHLO mail.dif.dk") by vger.kernel.org with ESMTP id S261617AbVCFXy1 (ORCPT ); Sun, 6 Mar 2005 18:54:27 -0500 Date: Mon, 7 Mar 2005 00:55:30 +0100 (CET) From: Jesper Juhl To: Yoichi Yuasa Cc: Andrew Morton , linux-kernel , Ralf Baechle Subject: Re: [PATCH 2.6.11-mm1] mips: more convert verify_area to access_ok In-Reply-To: <20050306232450.104fd7b7.yuasa@hh.iij4u.or.jp> Message-ID: References: <20050306232450.104fd7b7.yuasa@hh.iij4u.or.jp> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2757 Lines: 82 On Sun, 6 Mar 2005, Yoichi Yuasa wrote: > This patch converts verify_area to access_ok for include/asm-mips. > Yeah, that's one of the few bits I had not done yet. Thank you for taking a look at that. I don't believe your patch is correct though. See below for what I think is a better one. > Yoichi > > Signed-off-by: Yoichi Yuasa > > diff -urN -X dontdiff a-orig/include/asm-mips/uaccess.h a/include/asm-mips/uaccess.h > --- a-orig/include/asm-mips/uaccess.h Sat Mar 5 04:15:22 2005 > +++ a/include/asm-mips/uaccess.h Sun Mar 6 15:51:02 2005 > @@ -254,13 +254,11 @@ > ({ \ > __typeof__(*(ptr)) __gu_val = 0; \ > long __gu_addr; \ > - long __gu_err; \ > + long __gu_err = -EFAULT; \ > \ > might_sleep(); \ > __gu_addr = (long) (ptr); \ > - __gu_err = verify_area(VERIFY_READ, (void *) __gu_addr, size); \ > - \ > - if (likely(!__gu_err)) { \ > + if (access_ok(VERIFY_READ, (void *) __gu_addr, size)) { \ > switch (size) { \ > case 1: __get_user_asm("lb", __gu_err); break; \ > case 2: __get_user_asm("lh", __gu_err); break; \ with this change, __gu_err will always be -EFAULT. With the original code it was either -EFAULT or 0 depending on the return value from verify_area. Same goes for the next hunk in your patch. I believe a more correct patch would be this : Signed-off-by: Jesper Juhl diff -up linux-2.6.11-mm1-orig/include/asm-mips/uaccess.h linux-2.6.11-mm1/include/asm-mips/uaccess.h --- linux-2.6.11-mm1-orig/include/asm-mips/uaccess.h 2005-03-05 00:39:40.000000000 +0100 +++ linux-2.6.11-mm1/include/asm-mips/uaccess.h 2005-03-07 00:49:24.000000000 +0100 @@ -258,7 +258,8 @@ struct __large_struct { unsigned long bu \ might_sleep(); \ __gu_addr = (long) (ptr); \ - __gu_err = verify_area(VERIFY_READ, (void *) __gu_addr, size); \ + __gu_err = access_ok(VERIFY_READ, (void *) __gu_addr, size) \ + ? 0 : -EFAULT; \ \ if (likely(!__gu_err)) { \ switch (size) { \ @@ -353,7 +354,8 @@ extern void __get_user_unknown(void); might_sleep(); \ __pu_val = (x); \ __pu_addr = (long) (ptr); \ - __pu_err = verify_area(VERIFY_WRITE, (void *) __pu_addr, size); \ + __pu_err = access_ok(VERIFY_WRITE, (void *) __pu_addr, size) \ + ? 0 : -EFAULT; \ \ if (likely(!__pu_err)) { \ switch (size) { \ It preserves the exact behaviour of the original. -- Jesper - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/