diff options
| author | Zi Yan <[email protected]> | 2024-03-07 13:18:53 -0500 |
|---|---|---|
| committer | Andrew Morton <[email protected]> | 2024-03-12 13:07:17 -0700 |
| commit | 1412ecb3d256e5d23c6bd150e110cef6e3736844 (patch) | |
| tree | 3b4c9319b1ae4ef6a92f77669a9d79dc0d240dc3 | |
| parent | d221dd5fea6415cc6c7acb7d68c8e5dfd61c3902 (diff) | |
mm/huge_memory: check new folio order when split a folio
A folio can only be split into lower orders.
Since there are no new_order checks in debugfs, any new_order can be
passed via debugfs into split_huge_page_to_list_to_order().
Check new_order to make sure it is smaller than input folio order.
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c010d47f107f ("mm: thp: split huge page to any lower order pages")
Signed-off-by: Zi Yan <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Closes: https://lore.kernel.org/linux-mm/[email protected]/
Cc: David Hildenbrand <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
| -rw-r--r-- | mm/huge_memory.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index a81a09236c16..57fca7bffd20 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3052,6 +3052,9 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); + if (new_order >= folio_order(folio)) + return -EINVAL; + /* Cannot split anonymous THP to order-1 */ if (new_order == 1 && folio_test_anon(folio)) { VM_WARN_ONCE(1, "Cannot split to order-1 folio"); |