[PATCH] 64 bit bug in radix-tree lookup.

[Martin Schwidefsky]

[PATCH] 64 bit bug in radix-tree lookup.

The radix tree functions __lookup and __lookup_tag uses (1 << shift)
in their index calculations. On 64 bit systems the shift can be
bigger than 32. The shift of an integer by more than 32 bits evaluates
to zero which causes the lookup to fail.

Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>

diffstat:
 lib/radix-tree.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff -urN linux-2.6/lib/radix-tree.c linux-2.6-s390/lib/radix-tree.c
--- linux-2.6/lib/radix-tree.c	Wed Jun 30 17:06:23 2004
+++ linux-2.6-s390/lib/radix-tree.c	Wed Jun 30 17:06:32 2004
@@ -494,8 +494,8 @@
 		for ( ; i < RADIX_TREE_MAP_SIZE; i++) {
 			if (slot->slots[i] != NULL)
 				break;
-			index &= ~((1 << shift) - 1);
-			index += 1 << shift;
+			index &= ~((1UL << shift) - 1);
+			index += 1UL << shift;
 			if (index == 0)
 				goto out;	/* 32-bit wraparound */
 		}
@@ -584,8 +584,8 @@
 				BUG_ON(slot->slots[i] == NULL);
 				break;
 			}
-			index &= ~((1 << shift) - 1);
-			index += 1 << shift;
+			index &= ~((1UL << shift) - 1);
+			index += 1UL << shift;
 			if (index == 0)
 				goto out;	/* 32-bit wraparound */
 		}
-
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