From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753995Ab0G2HyP (ORCPT ); Thu, 29 Jul 2010 03:54:15 -0400 Received: from mail-pw0-f46.google.com ([209.85.160.46]:37587 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750938Ab0G2HyM (ORCPT ); Thu, 29 Jul 2010 03:54:12 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=gBTzCgX0sVSyxF+pkT7o51gWmLLTdz7nA5+mnJRotk85/baUhocctSxrPvchzQwRBE 5USmmVjhDkGFuI41ko5urxk5he4CDGi/je3D9HXIiCUc04UkinsiNJM/b9jivH04TSr/ DyCn1Z6LwEmFy2ReJY2FzKZe+CsW8sClszess= Date: Thu, 29 Jul 2010 15:58:15 +0800 From: =?utf-8?Q?Am=C3=A9rico?= Wang To: Dan Carpenter , Andrew Morton , Hidetoshi Seto , "Paul E. McKenney" , "Eric W. Biederman" , Simon Kagstrom , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [patch] kexec: return -EFAULT on copy_to_user() failures Message-ID: <20100729075815.GA5555@cr0.nay.redhat.com> References: <20100729073609.GR26313@bicker> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100729073609.GR26313@bicker> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 29, 2010 at 09:36:10AM +0200, Dan Carpenter wrote: >copy_to/from_user() returns the number of bytes remaining to be copied. >It never returns a negative value. The correct return code is -EFAULT >and not -EIO. > >All the callers check for non-zero returns so that's Ok, but the return >code is passed to the user so we should fix this. > >Signed-off-by: Dan Carpenter Acked-by: WANG Cong > >diff --git a/kernel/kexec.c b/kernel/kexec.c >index 474a847..ab2258b 100644 >--- a/kernel/kexec.c >+++ b/kernel/kexec.c >@@ -151,8 +151,10 @@ static int do_kimage_alloc(struct kimage **rimage, unsigned long entry, > image->nr_segments = nr_segments; > segment_bytes = nr_segments * sizeof(*segments); > result = copy_from_user(image->segment, segments, segment_bytes); >- if (result) >+ if (result) { >+ result = -EFAULT; > goto out; >+ } > > /* > * Verify we have good destination addresses. The caller is >@@ -827,7 +829,7 @@ static int kimage_load_normal_segment(struct kimage *image, > result = copy_from_user(ptr, buf, uchunk); > kunmap(page); > if (result) { >- result = (result < 0) ? result : -EIO; >+ result = -EFAULT; > goto out; > } > ubytes -= uchunk; >@@ -882,7 +884,7 @@ static int kimage_load_crash_segment(struct kimage *image, > kexec_flush_icache_page(page); > kunmap(page); > if (result) { >- result = (result < 0) ? result : -EIO; >+ result = -EFAULT; > goto out; > } > ubytes -= uchunk; >-- >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/