Re: [syzbot] [arm-msm?] [net?] memory leak in radix_tree_insert

[syzbot <syzbot+006987d1be3586e13555@syzkaller.appspotmail.com>]

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Subject: [arm-msm?] [net?] memory leak in radix_tree_insert
Author: lizhi.xu@windriver.com

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 33cc938e65a9

diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 976b9bd02a1b..b98e9f2c24ac 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -55,6 +55,8 @@ struct kmem_cache *radix_tree_node_cachep;
 #define IDR_MAX_PATH		(DIV_ROUND_UP(IDR_INDEX_BITS, \
 						RADIX_TREE_MAP_SHIFT))
 #define IDR_PRELOAD_SIZE	(IDR_MAX_PATH * 2 - 1)
+static bool __radix_tree_delete(struct radix_tree_root *root,
+				struct radix_tree_node *node, void __rcu **slot);
 
 /*
  * Per-cpu pool of preloaded nodes
@@ -714,8 +716,10 @@ int radix_tree_insert(struct radix_tree_root *root, unsigned long index,
 		return error;
 
 	error = insert_entries(node, slot, item);
-	if (error < 0)
+	if (error < 0) {
+		__radix_tree_delete(root, node, slot);
 		return error;
+	}
 
 	if (node) {
 		unsigned offset = get_slot_offset(node, slot);
-- 
2.43.0