ACK: [PATCH] lib: fwts_args: ensure a null short_option is never passed to getopt_long

[Alex Hung]

On 2017-11-09 08:30 PM, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
> 
> Although very unlikely, ensure a null getopt_long is never passed to a call
> to getopt_long as this would lead to a null pointer derference.  Also add
> a fix to a leak on short_options if an allocation fails.
> 
> Detected by CoverityScan, CID#1381432 ("Explicit Null dereference")
> 
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>   src/lib/src/fwts_args.c | 17 +++++++++++++++++
>   1 file changed, 17 insertions(+)
> 
> diff --git a/src/lib/src/fwts_args.c b/src/lib/src/fwts_args.c
> index 23eb0c83..d4b1a3c1 100644
> --- a/src/lib/src/fwts_args.c
> +++ b/src/lib/src/fwts_args.c
> @@ -154,6 +154,7 @@ int fwts_args_parse(fwts_framework *fw, const int argc, char * const argv[])
>   				} else {
>   					short_options = calloc(1, len + 1);
>   					if (short_options == NULL) {
> +						free(short_options);
>   						free(long_options);
>   						fwts_log_error(fw,
>   							"Out of memory "
> @@ -167,6 +168,22 @@ int fwts_args_parse(fwts_framework *fw, const int argc, char * const argv[])
>   		}
>   	}
>   
> +	/*
> +	 *  Although unlikely, short_options must not be null otherwise
> +	 *  it could potentially break getopt_long() so to be totally
> +	 *  safe, allocate a empty string.
> +	 *  Cleans up CoverityScan CID#1381432 ("Explicit Null dereference")
> +	 */
> +	if (!short_options) {
> +		short_options = strdup("");
> +		if (!short_options) {
> +			free(short_options);
> +			free(long_options);
> +			fwts_log_error(fw, "Out of memory allocating options.");
> +			return FWTS_ERROR;
> +		}
> +	}
> +
>   	for (;;) {
>   		master_option_index = total_options;
>   		translated_long_option_index = 0;
> 

Acked-by: Alex Hung <alex.hung at canonical.com>