[v2,1/3] maple_tree: Fix get wrong data_end in mtree_lookup_walk()

Commit Message

Peng Zhang March 14, 2023, 12:42 p.m. UTC

if (likely(offset > end))
	max = pivots[offset];

The above code should be changed to if (likely(offset < end)), which is
correct. This affects the correctness of ma_data_end(). Now it seems
that the final result will not be wrong, but it is best to change it.
This patch does not change the code as above, because it simplifies the
code by the way.

Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Peng Zhang <[e-mail]>
Reviewed-by: Liam R. Howlett <[e-mail]>
---
 lib/maple_tree.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

Patch

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 646297cae5d1..b3164266cfde 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3875,18 +3875,13 @@  static inline void *mtree_lookup_walk(struct ma_state *mas)
 		end = ma_data_end(node, type, pivots, max);
 		if (unlikely(ma_dead_node(node)))
 			goto dead_node;
-
-		if (pivots[offset] >= mas->index)
-			goto next;
-
 		do {
-			offset++;
-		} while ((offset < end) && (pivots[offset] < mas->index));
-
-		if (likely(offset > end))
-			max = pivots[offset];
+			if (pivots[offset] >= mas->index) {
+				max = pivots[offset];
+				break;
+			}
+		} while (++offset < end);
 
-next:
 		slots = ma_slots(node, type);
 		next = mt_slot(mas->tree, slots, offset);
 		if (unlikely(ma_dead_node(node)))