Re: [PATCH] ASN.1: mark expected switch fall-throughs

[Kees Cook]

On Sat, Jan 26, 2019 at 9:49 AM Gustavo A. R. Silva
<gustavo@xxxxxxxxxxxxxx> wrote:
>
> In preparation to enabling -Wimplicit-fallthrough, mark switch
> cases where we are expecting to fall through.
>
> This patch fixes the following warnings:
>
> lib/asn1_decoder.c:386:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
> lib/asn1_decoder.c:449:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
>
> Warning level 3 was used: -Wimplicit-fallthrough=3
>
> This patch is part of the ongoing efforts to enabling
> -Wimplicit-fallthrough.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-Kees

> ---
>  lib/asn1_decoder.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c
> index dc14beae2c9a..8f3d207d2b00 100644
> --- a/lib/asn1_decoder.c
> +++ b/lib/asn1_decoder.c
> @@ -385,6 +385,8 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
>         case ASN1_OP_END_SET_ACT:
>                 if (unlikely(!(flags & FLAG_MATCHED)))
>                         goto tag_mismatch;
> +               /* fall through */
> +
>         case ASN1_OP_END_SEQ:
>         case ASN1_OP_END_SET_OF:
>         case ASN1_OP_END_SEQ_OF:
> @@ -450,6 +452,8 @@ int asn1_ber_decoder(const struct asn1_decoder *decoder,
>                         pc += asn1_op_lengths[op];
>                         goto next_op;
>                 }
> +               /* fall through */
> +
>         case ASN1_OP_ACT:
>                 ret = actions[machine[pc + 1]](context, hdr, tag, data + tdp, len);
>                 if (ret < 0)
> --
> 2.20.1
>


-- 
Kees Cook