RE: [PATCH 1/2] efi: Fix cast to pointer from integer of different size in TPM log code

[David Laight]

From: Matthew Garrett
> Sent: 02 April 2019 22:56
> 
> 8bfcff4a6a1d9d7226bb63a7da758b82d9ab4373 introduced a cast from
> efi_physical_address_t to (void *), which are different sizes on 32-bit.
> Fix that. Caught by the 0-day test bot.

Casting a physical address to 'void *' seems completely wrong.
Also you'd need a guarantee that the address was below 4G or the result
is meaningless.
Looks to me like something is using the wrong types somewhere.

	David

> Signed-off-by: Matthew Garrett <mjg59@xxxxxxxxxx>
> ---
>  drivers/firmware/efi/libstub/tpm.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c
> index b6e93e14fcf1..6b3b507a54eb 100644
> --- a/drivers/firmware/efi/libstub/tpm.c
> +++ b/drivers/firmware/efi/libstub/tpm.c
> @@ -114,8 +114,8 @@ void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table_arg)
>  			 */
>  			last_entry_size =
>  				__calc_tpm2_event_size((void *)last_entry_addr,
> -						       (void *)log_location,
> -						       false);
> +						    (void *)(long)log_location,
> +						    false);
>  		} else {
>  			last_entry_size = sizeof(struct tcpa_event) +
>  			   ((struct tcpa_event *) last_entry_addr)->event_size;
> --
> 2.21.0.392.gf8f6787159e-goog

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