linux-kernel - [PATCH] mm, hugetlb: correct bit shift in hstate

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>] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 21 Oct 2014 14:15:07 -0400
From:	Sasha Levin <sasha.levin@...cle.com>
To:	akpm@...ux-foundation.org
Cc:	n-horiguchi@...jp.nec.com, aarcange@...hat.com, mgorman@...e.de,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	a.ryabinin@...sung.com, Sasha Levin <sasha.levin@...cle.com>
Subject: [PATCH] mm, hugetlb: correct bit shift in hstate_sizelog

hstate_sizelog() would shift left an int rather than long, triggering
undefined behaviour and passing an incorrect value when the requested
page size was more than 4GB, thus breaking >4GB pages.

Signed-off-by: Sasha Levin <sasha.levin@...cle.com>
---
 include/linux/hugetlb.h |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 65e12a2..57e0dfd 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -312,7 +312,8 @@ static inline struct hstate *hstate_sizelog(int page_size_log)
 {
 	if (!page_size_log)
 		return &default_hstate;
-	return size_to_hstate(1 << page_size_log);
+
+	return size_to_hstate(1UL << page_size_log);
 }
 
 static inline struct hstate *hstate_vma(struct vm_area_struct *vma)
-- 
1.7.10.4

--
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/