diff --git a/mm/usercopy.c b/mm/usercopy.c index 51411f9c4068263048db4a039091eb055b4ad569..e81d11715d95b34d1e99e57dc0fd398e9a9e0cbe 100644 --- a/mm/usercopy.c +++ b/mm/usercopy.c @@ -15,6 +15,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include +#include #include #include #include @@ -231,7 +232,12 @@ static inline void check_heap_object(const void *ptr, unsigned long n, if (!virt_addr_valid(ptr)) return; - page = virt_to_head_page(ptr); + /* + * When CONFIG_HIGHMEM=y, kmap_to_page() will give either the + * highmem page or fallback to virt_to_page(). The following + * is effectively a highmem-aware virt_to_head_page(). + */ + page = compound_head(kmap_to_page((void *)ptr)); if (PageSlab(page)) { /* Check slab allocator for flags and size. */