In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Use memset_after() to zero the end of struct mlx5_ib_mr that should be initialized. Cc: Doug Ledford <dledford@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxx> Cc: linux-rdma@xxxxxxxxxxxxxxx Acked-by: Leon Romanovsky <leonro@xxxxxxxxxx> Link: https://lore.kernel.org/lkml/YbByJSkBgLRp5S8V@unreal Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/mlx5_ib.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h index 4a7a56ed740b..ded10719b643 100644 --- a/drivers/infiniband/hw/mlx5/mlx5_ib.h +++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h @@ -664,8 +664,8 @@ struct mlx5_ib_mr { /* User MR data */ struct mlx5_cache_ent *cache_ent; + /* Everything after cache_ent is zero'd when MR allocated */ - /* This is zero'd when the MR is allocated */ union { /* Used only while the MR is in the cache */ struct { @@ -718,7 +718,7 @@ struct mlx5_ib_mr { /* Zero the fields in the mr that are variant depending on usage */ static inline void mlx5_clear_mr(struct mlx5_ib_mr *mr) { - memset(mr->out, 0, sizeof(*mr) - offsetof(struct mlx5_ib_mr, out)); + memset_after(mr, 0, cache_ent); } static inline bool is_odp_mr(struct mlx5_ib_mr *mr) -- 2.30.2
