On Tue, Oct 3, 2023 at 4:17 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for > array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct mlx5_flow_handle. > > Cc: Saeed Mahameed <saeedm@xxxxxxxxxx> > Cc: Leon Romanovsky <leon@xxxxxxxxxx> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> > Cc: Eric Dumazet <edumazet@xxxxxxxxxx> > Cc: Jakub Kicinski <kuba@xxxxxxxxxx> > Cc: Paolo Abeni <pabeni@xxxxxxxxxx> > Cc: netdev@xxxxxxxxxxxxxxx > Cc: linux-rdma@xxxxxxxxxxxxxxx > Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1] > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > --- > drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h > index 4aed1768b85f..78eb6b7097e1 100644 > --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h > +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h > @@ -181,7 +181,7 @@ struct mlx5_flow_rule { > > struct mlx5_flow_handle { > int num_rules; > - struct mlx5_flow_rule *rule[]; > + struct mlx5_flow_rule *rule[] __counted_by(num_rules); > }; Great patch! handle->num_rules is properly assigned to before handle->rule has any accesses. handle = alloc_handle((dest_num) ? dest_num : 1); then static struct mlx5_flow_handle *alloc_handle(int num_rules) { ... handle->num_rules = num_rules; then handle->rule[i] = rule; Reviewed-by: Justin Stitt <justinstitt@xxxxxxxxxx> > > /* Type of children is mlx5_flow_group */ > -- > 2.34.1 > > Thanks Justin
