net: page_pool: sanitise allocation order

We're going to give more control over rx buffer sizes to user space, and
since we can't always rely on driver validation, let's sanitise it in
page_pool_init() as well. Note that we only need to reject over
MAX_PAGE_ORDER allocations for normal page pools, as current memory
providers don't need to use the buddy allocator and must check the order
on init.i

Suggested-by: Stanislav Fomichev <[email protected]>
Reviewed-by: Mina Almasry <[email protected]>
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://patch.msgid.link/77ad83c1aec66cbd00e7b3952f74bc3b7a988150.1764542851.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>

Author: isilence

net/core/page_pool.c

@@ -301,6 +301,9 @@ static int page_pool_init(struct page_pool *pool,
 		}
 
 		static_branch_inc(&page_pool_mem_providers);
+	} else if (pool->p.order > MAX_PAGE_ORDER) {
+		err = -EINVAL;
+		goto free_ptr_ring;
 	}
 
 	return 0;