[PATCH 11/30] radix-tree: Fix deleting a multi-order entry through an alias

From: Matthew Wilcox
Date: Wed Apr 06 2016 - 17:29:59 EST


If we deleted an entry through an index which looked up a sibling
pointer, we'd end up zeroing out the wrong slots in the node.
Use get_sibling_offset() to find the right slot.

Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>
Reviewed-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
---
lib/radix-tree.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 42a0492b2ba2..554986599c63 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -1557,7 +1557,7 @@ void *radix_tree_delete_item(struct radix_tree_root *root,
return entry;
}

- offset = index & RADIX_TREE_MAP_MASK;
+ offset = get_sibling_offset(node, slot);

/*
* Clear all tags associated with the item to be deleted.
--
2.8.0.rc3