linux-kernel - [tip: x86/kaslr] x86/kaslr: Fix off-by-one error in process_gb_huge

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Date:   Thu, 06 Aug 2020 23:38:57 -0000
From:   "tip-bot2 for Arvind Sankar" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Arvind Sankar <nivedita@...m.mit.edu>,
        Ingo Molnar <mingo@...nel.org>, x86 <x86@...nel.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: [tip: x86/kaslr] x86/kaslr: Fix off-by-one error in process_gb_huge_pages()

The following commit has been merged into the x86/kaslr branch of tip:

Commit-ID:     79c2fd2afe55944098047721c33e06fd48654e57
Gitweb:        https://git.kernel.org/tip/79c2fd2afe55944098047721c33e06fd48654e57
Author:        Arvind Sankar <nivedita@...m.mit.edu>
AuthorDate:    Tue, 28 Jul 2020 18:57:11 -04:00
Committer:     Ingo Molnar <mingo@...nel.org>
CommitterDate: Fri, 31 Jul 2020 11:08:17 +02:00

x86/kaslr: Fix off-by-one error in process_gb_huge_pages()

If the remaining size of the region is exactly 1Gb, there is still one
hugepage that can be reserved.

Signed-off-by: Arvind Sankar <nivedita@...m.mit.edu>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Link: https://lore.kernel.org/r/20200728225722.67457-11-nivedita@alum.mit.edu
---
 arch/x86/boot/compressed/kaslr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index d074986..0df513e 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -562,7 +562,7 @@ process_gb_huge_pages(struct mem_vector *region, unsigned long image_size)
 		size = region->size - (addr - region->start);
 
 	/* Check how many 1GB huge pages can be filtered out: */
-	while (size > PUD_SIZE && max_gb_huge_pages) {
+	while (size >= PUD_SIZE && max_gb_huge_pages) {
 		size -= PUD_SIZE;
 		max_gb_huge_pages--;
 		i++;