From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932308Ab0JZVl1 (ORCPT ); Tue, 26 Oct 2010 17:41:27 -0400 Received: from g5t0006.atlanta.hp.com ([15.192.0.43]:16347 "EHLO g5t0006.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758504Ab0JZVlZ (ORCPT ); Tue, 26 Oct 2010 17:41:25 -0400 Subject: [PATCH v5 3/9] resources: ensure callback doesn't allocate outside available space To: Jesse Barnes From: Bjorn Helgaas Cc: Bob Picco , Brian Bloniarz , Charles Butterfield , Denys Vlasenko , Ingo Molnar , linux-pci@vger.kernel.org, "Horst H. von Brand" , "H. Peter Anvin" , linux-kernel@vger.kernel.org, Stefan Becker , Chuck Ebbert , Fabrice Bellet , Yinghai Lu , Leann Ogasawara , Linus Torvalds , Thomas Gleixner Date: Tue, 26 Oct 2010 15:41:23 -0600 Message-ID: <20101026214123.29808.24645.stgit@bob.kio> In-Reply-To: <20101026214033.29808.15272.stgit@bob.kio> References: <20101026214033.29808.15272.stgit@bob.kio> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The alignment callback returns a proposed location, which may have been adjusted to avoid ISA aliases or for other architecture-specific reasons. We already had a check ("tmp.start < tmp.end") to make sure the callback doesn't return an area that extends past the available area. This patch reworks the check to make sure it doesn't return an area that extends either below or above the available area. Signed-off-by: Bjorn Helgaas --- kernel/resource.c | 16 +++++++++++----- 1 files changed, 11 insertions(+), 5 deletions(-) diff --git a/kernel/resource.c b/kernel/resource.c index 26e9f25..89d5041 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -374,6 +374,11 @@ static void resource_clip(struct resource *res, resource_size_t min, res->end = max; } +static bool resource_contains(struct resource *res1, struct resource *res2) +{ + return res1->start <= res2->start && res1->end >= res2->end; +} + /* * Find empty slot in the resource tree given range and alignment. */ @@ -387,7 +392,7 @@ static int find_resource(struct resource *root, struct resource *new, void *alignf_data) { struct resource *this = root->child; - struct resource tmp = *new; + struct resource tmp = *new, alloc; tmp.start = root->start; /* @@ -407,10 +412,11 @@ static int find_resource(struct resource *root, struct resource *new, resource_clip(&tmp, min, max); tmp.start = ALIGN(tmp.start, align); - tmp.start = alignf(alignf_data, &tmp, size, align); - if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) { - new->start = tmp.start; - new->end = tmp.start + size - 1; + alloc.start = alignf(alignf_data, &tmp, size, align); + alloc.end = alloc.start + size - 1; + if (resource_contains(&tmp, &alloc)) { + new->start = alloc.start; + new->end = alloc.end; return 0; } if (!this)