ACK: [PATCH] lib: fwts_pipeio: don't report failure on freopen failure

[ivanhu]

On 2016年07月23日 00:26, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
>
> A freopen failure on stderr means that stderr is NULL so printing
> an error to that file pointer will lead to a null pointer dereference.
> Silently ignore a failure.
>
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>  src/lib/src/fwts_pipeio.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/src/lib/src/fwts_pipeio.c b/src/lib/src/fwts_pipeio.c
> index f62621a..68f1ff6 100644
> --- a/src/lib/src/fwts_pipeio.c
> +++ b/src/lib/src/fwts_pipeio.c
> @@ -78,9 +78,11 @@ int fwts_pipe_open_rw(const char *command, pid_t *childpid,
>  		goto err_close_out;
>  	case 0:
>  		/* Child */
> -		if ((fp = freopen("/dev/null", "w", stderr)) == NULL) {
> -			fprintf(stderr, "Cannot redirect stderr\n");
> -		}
> +		fp = freopen("/dev/null", "w", stderr);
> +		/*
> +		 * if null, we can't report freopen failed
> +		 * to stderr as it is now free
> +		 */
>  		if (out_pipefds[0] != STDOUT_FILENO) {
>  			dup2(out_pipefds[1], STDOUT_FILENO);
>  			close(out_pipefds[1]);
>

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