Re: [PATCH 2/2] libxl: fix -Werror=stringop-truncation in libxl__prepare_sockaddr_un

[Elliott Mitchell <ehem+xen@xxxxxxx>]

On Wed, Aug 19, 2020 at 04:00:36AM +0200, Marek Marczykowski-G??recki wrote:
> diff --git a/tools/libxl/libxl_utils.c b/tools/libxl/libxl_utils.c
> index f360f5e228..b039143b8a 100644
> --- a/tools/libxl/libxl_utils.c
> +++ b/tools/libxl/libxl_utils.c


>      }
>      memset(un, 0, sizeof(struct sockaddr_un));
>      un->sun_family = AF_UNIX;
> -    strncpy(un->sun_path, path, sizeof(un->sun_path));
> +    strncpy(un->sun_path, path, sizeof(un->sun_path) - 1);
>      return 0;
>  }

While the earlier lines are okay, this line introduces an error.  If the
compiler complains once the earlier lines are fixed, something might need
to be done about this.

I would be tempted to switch to strlcpy() since this doesn't look like it
needs un->sun_path to be zeroed out.  (note I'm not familiar with this
code, so someone else needs to check me on this)


-- 
(\___(\___(\______          --=> 8-) EHM <=--          ______/)___/)___/)
 \BS (    |         ehem+sigmsg@xxxxxxx  PGP 87145445         |    )   /
  \_CS\   |  _____  -O #include <stddisclaimer.h> O-   _____  |   /  _/
8A19\___\_|_/58D2 7E3D DDF4 7BA6 <-PGP-> 41D1 B375 37D0 8714\_|_/___/5445