On Sun, Jul 28, 2019 at 06:19:20PM -0500, Gustavo A. R. Silva wrote:
> Mark switch cases where we are expecting to fall through.
>
> This patch fixes the following warnings:
>
> arch/arm/mm/alignment.c: In function 'thumb2arm':
> arch/arm/mm/alignment.c:688:6: warning: this statement may fall through
> [-Wimplicit-fallthrough=]
> if ((tinstr & (3 << 9)) == 0x0400) {
> ^
> arch/arm/mm/alignment.c:700:2: note: here
> default:
> ^~~~~~~
> arch/arm/mm/alignment.c: In function 'do_alignment_t32_to_handler':
> arch/arm/mm/alignment.c:753:15: warning: this statement may fall through
> [-Wimplicit-fallthrough=]
> poffset->un = (tinst2 & 0xff) << 2;
> ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
> arch/arm/mm/alignment.c:754:2: note: here
> case 0xe940:
> ^~~~
>
> Reported-by: Stephen Rothwell <[email protected]>
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
-Kees
> ---
> arch/arm/mm/alignment.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
> index 8cdb78642e93..04b36436cbc0 100644
> --- a/arch/arm/mm/alignment.c
> +++ b/arch/arm/mm/alignment.c
> @@ -695,7 +695,7 @@ thumb2arm(u16 tinstr)
> return subset[(L<<1) | ((tinstr & (1<<8)) >> 8)] |
> (tinstr & 255); /* register_list */
> }
> - /* Else fall through for illegal instruction case */
> + /* Else, fall through - for illegal instruction case */
>
> default:
> return BAD_INSTR;
> @@ -751,6 +751,8 @@ do_alignment_t32_to_handler(unsigned long *pinstr, struct
> pt_regs *regs,
> case 0xe8e0:
> case 0xe9e0:
> poffset->un = (tinst2 & 0xff) << 2;
> + /* Fall through */
> +
> case 0xe940:
> case 0xe9c0:
> return do_alignment_ldrdstrd;
> --
> 2.22.0
>
--
Kees Cook
