From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Wed, 30 Nov 2022 16:33:54 +0000 (-0500)
Subject: maple_tree: Avoid crashing on mte_set_pivot() out of range
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=5dfc819cee0c8a021828d68c897d68bde23e51fe;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Avoid crashing on mte_set_pivot() out of range

Emit a warning and return.  The tree will be in an undefined state, but
the warning is more likely to be recorded.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 7466a6f0a2ab..766f257a98a4 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -762,7 +762,9 @@ static inline void mte_set_pivot(struct maple_enode *mn, unsigned char piv,
 	struct maple_node *node = mte_to_node(mn);
 	enum maple_type type = mte_node_type(mn);
 
-	BUG_ON(piv >= mt_pivots[type]);
+	if (WARN_ON_ONCE(piv >= mt_pivots[type]))
+		return;
+
 	switch (type) {
 	default:
 	case maple_range_64: