[v4,02/49] maple_tree: Fix potential rcu issue

Message ID 20230120162650.984577-3-Liam.Howlett@oracle.com
State New
Headers
Series VMA tree type safety and remove __vma_adjust() |

Commit Message

Liam R. Howlett Jan. 20, 2023, 4:26 p.m. UTC
  From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>

Ensure the node isn't dead after reading the node end.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 lib/maple_tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Patch

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index cb8c03c4dce7..cbb8bd9b9d25 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -4654,13 +4654,13 @@  static inline void *mas_next_nentry(struct ma_state *mas,
 	pivots = ma_pivots(node, type);
 	slots = ma_slots(node, type);
 	mas->index = mas_safe_min(mas, pivots, mas->offset);
+	count = ma_data_end(node, type, pivots, mas->max);
 	if (ma_dead_node(node))
 		return NULL;
 
 	if (mas->index > max)
 		return NULL;
 
-	count = ma_data_end(node, type, pivots, mas->max);
 	if (mas->offset > count)
 		return NULL;