ACK: [PATCH] lib: fwts_acpi: fix potential infinite loop in data copy

[ivanhu]

On 3/30/21 6:39 PM, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
>
> The loop index i is a uint8_t however it is being compared to an
> upper loop limit that is a wider type of size_t. When i reaches
> 255 it will wrap around to 0 and the loop will never exit. Fix this
> by making i a size_t type.
>
> Addresses-Coverity: ("Infinite loop")
> Fixes: 4ad3e374bf98 ("acpi: fadt: X_GPE0/1_BLK can be zero when not used")
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>  src/lib/src/fwts_acpi.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/src/lib/src/fwts_acpi.c b/src/lib/src/fwts_acpi.c
> index 89378d0e..2e95bc77 100644
> --- a/src/lib/src/fwts_acpi.c
> +++ b/src/lib/src/fwts_acpi.c
> @@ -59,9 +59,10 @@ void fwts_acpi_table_get_header(fwts_acpi_table_header *hdr, uint8_t *data)
>  	memcpy(hdr, data, sizeof(fwts_acpi_table_header));
>  }
>  
> -bool fwts_acpi_data_zero(const void *data, const size_t len) {
> +bool fwts_acpi_data_zero(const void *data, const size_t len)
> +{
>  	uint8_t *ptr = (uint8_t *) data;
> -	uint8_t i;
> +	size_t i;
>  
>  	for (i = 0; i < len; i++)
>  		if (*ptr++)


Acked-by: Ivan Hu <ivan.hu at canonical.com>