linux-kernel - [PATCH] __ioremap_caller(): make check for ioremapping of RAM cover complete mapping

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Tue, 15 Jun 2010 19:10:11 +0200
From:	Florian Zumbiehl <florz@...rz.de>
To:	linux-kernel@...r.kernel.org
Subject: [PATCH] __ioremap_caller(): make check for ioremapping of RAM
	cover complete mapping

Hi,

the patch is untested and someone with detailed understanding of the
semantics of this code probably should check for correctness of
the fixed version in corner cases.

Florian
---------------------------------------------------------------------------
x86 __ioremap_caller(): fix check for overlap with RAM to check the
last page of the mapping as well.

Signed-off-by: Florian Zumbiehl <florz@...rz.de>

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index a4643e5..4c3e4f9 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -101,7 +101,7 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
 	 * Don't allow anybody to remap normal RAM that we're using..
 	 */
 	for (pfn = phys_addr >> PAGE_SHIFT;
-				(pfn << PAGE_SHIFT) < (last_addr & PAGE_MASK);
+				pfn <= (last_addr >> PAGE_SHIFT);
 				pfn++) {
 
 		int is_ram = page_is_ram(pfn);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/