[PATCH net-next v6 1/8] net: page_pool: sanitise allocation order

[Pavel Begunkov <asml.silence@gmail.com>]

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 <stfomichev@gmail.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 net/core/page_pool.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 1a5edec485f1..635c77e8050b 100644
--- a/net/core/page_pool.c
+++ b/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;
-- 
2.52.0