diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/radix-tree.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/lib/radix-tree.c b/lib/radix-tree.c index e907858498a6..5b7d4623f0b7 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -625,6 +625,8 @@ EXPORT_SYMBOL(radix_tree_tag_get); * * The function returns number of leaves where the tag was set and sets * *first_indexp to the first unscanned index. + * WARNING! *first_indexp can wrap if last_index is ULONG_MAX. Caller must + * be prepared to handle that. */ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, unsigned long *first_indexp, unsigned long last_index, @@ -675,7 +677,8 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, next: /* Go to next item at level determined by 'shift' */ index = ((index >> shift) + 1) << shift; - if (index > last_index) + /* Overflow can happen when last_index is ~0UL... */ + if (index > last_index || !index) break; if (tagged >= nr_to_tag) break; |