From aa447b9c501c649628ef0f646f59befa79126bd0 Mon Sep 17 00:00:00 2001
From: Sandrine Bailleux <sandrine.bailleux@arm.com>
Date: Fri, 22 Apr 2016 10:47:33 +0100
Subject: [PATCH] Fix computation of L1 bitmask in the translation table lib

This patch fixes the computation of the bitmask used to isolate
the level 1 field of a virtual address. The whole computation needs
to work on 64-bit values to produce the correct bitmask value.
XLAT_TABLE_ENTRIES_MASK being a C constant, it is a 32-bit value
so it needs to be extended to a 64-bit value before it takes part
in any other computation.

This patch fixes this bug by casting XLAT_TABLE_ENTRIES_MASK as
an unsigned long long.

Note that this bug doesn't manifest itself in practice because
address spaces larger than 39 bits are not yet supported in the
Trusted Firmware.

Change-Id: I955fd263ecb691ca94b29b9c9f576008ce1d87ee
---
 lib/xlat_tables/xlat_tables_common.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/xlat_tables/xlat_tables_common.c b/lib/xlat_tables/xlat_tables_common.c
index 54c528cd8..fd1008464 100644
--- a/lib/xlat_tables/xlat_tables_common.c
+++ b/lib/xlat_tables/xlat_tables_common.c
@@ -284,8 +284,9 @@ static mmap_region_t *init_xlation_table_inner(mmap_region_t *mm,
 	unsigned level_size_shift = L1_XLAT_ADDRESS_SHIFT - (level - 1) *
 						XLAT_TABLE_ENTRIES_SHIFT;
 	unsigned level_size = 1 << level_size_shift;
-	unsigned long long level_index_mask = XLAT_TABLE_ENTRIES_MASK <<
-							level_size_shift;
+	unsigned long long level_index_mask =
+		((unsigned long long) XLAT_TABLE_ENTRIES_MASK)
+		<< level_size_shift;
 
 	assert(level > 0 && level <= 3);
 
-- 
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