ACK: [PATCH] compiler: fwts_iasl_interface: free original string on failed realloc

[ivanhu]

On 04/13/2017 06:05 PM, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
>
> A common bug is where realloc fails to allocate and we assume that
> the memory being realloc'd was freed. This is not the case, the
> NULL return means we need to free the original string to avoid
> a memory leak.
>
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>  src/acpica/source/compiler/fwts_iasl_interface.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/src/acpica/source/compiler/fwts_iasl_interface.c b/src/acpica/source/compiler/fwts_iasl_interface.c
> index b110c10c..1020512b 100644
> --- a/src/acpica/source/compiler/fwts_iasl_interface.c
> +++ b/src/acpica/source/compiler/fwts_iasl_interface.c
> @@ -170,8 +170,15 @@ static int fwts_iasl_read_output(const int fd, char **data, size_t *len, bool *e
>  		return 0;
>
>  	while ((n = read(fd, buffer, sizeof(buffer))) > 0) {
> -		if ((*data = realloc(*data, *len + n + 1)) == NULL)
> +		char *tmp;
> +
> +		tmp = realloc(*data, *len + n + 1);
> +		if (!tmp) {
> +			free(*data);
> +			*data = NULL;
>  			return -1;
> +		}
> +		*data = tmp;
>  		memcpy(*data + *len, buffer, n);
>  		*len += n;
>  		(*data)[*len] = '\0';
>

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