get_slot_offset() can be called with a NULL 'parent' argument.
In this case, the calculated value will not be used, but calculating
it is undefined.  Rather than fixing the caller (__radix_tree_delete)
to not call get_slot_offset(), make get_slot_offset() robust against
being called with a NULL parent.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
This commit is contained in:
Matthew Wilcox 2018-08-18 07:05:50 -04:00
Родитель d1c0d5e3c6
Коммит 76f070b413
1 изменённых файлов: 1 добавлений и 1 удалений

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@ -120,7 +120,7 @@ bool is_sibling_entry(const struct radix_tree_node *parent, void *node)
static inline unsigned long
get_slot_offset(const struct radix_tree_node *parent, void __rcu **slot)
{
return slot - parent->slots;
return parent ? slot - parent->slots : 0;
}
static unsigned int radix_tree_descend(const struct radix_tree_node *parent,