From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= <roger.pau@citrix.com>
Subject: Re: [Patch v3 3/4] tools/libxl: Fix
	libxl__device_nic_from_xs_be()
Date: Tue, 26 Nov 2013 09:11:17 +0100
Message-ID: <529457A5.2090106@citrix.com>
References: <52939C67.7020108@citrix.com>
	<1385412567-7717-1-git-send-email-andrew.cooper3@citrix.com>
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To: Andrew Cooper <andrew.cooper3@citrix.com>, Xen-devel <xen-devel@lists.xen.org>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>, Ian Campbell <Ian.Campbell@citrix.com>
List-Id: xen-devel@lists.xenproject.org

On 25/11/13 21:49, Andrew Cooper wrote:
> Coverity ID: 1055886
> =

> Replace uses of xs_read() with libxl__xs_read_checked() which appropriate=
ly
> garbage-collects the allocated string, and avoid executing
> libxl__parse_mac(NULL,) if the second xenstore read fails.
> =

> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
> CC: Ian Campbell <Ian.Campbell@citrix.com>
> CC: Ian Jackson <Ian.Jackson@eu.citrix.com>
> CC: Roger Pau Monne <roger.pau@citrix.com>

Acked-by: Roger Pau Monn=E9 <roger.pau@citrix.com>

> =

> ---
> Changes in v3:
>  * Less hypervisor coding style
>  * Slightly easier-to-read error conditional for nic->mac
> =

> Changes in v2:
>  * Use libxl__xs_read_checked() in preference to xs_read() and free()
> ---
>  tools/libxl/libxl.c |   20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> =

> diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
> index 2b847ef..3237354 100644
> --- a/tools/libxl/libxl.c
> +++ b/tools/libxl/libxl.c
> @@ -2982,24 +2982,28 @@ static void libxl__device_nic_from_xs_be(libxl__g=
c *gc,
>  {
>      libxl_ctx *ctx =3D libxl__gc_owner(gc);
>      unsigned int len;
> -    char *tmp;
> +    const char *tmp;
>      int rc;
>  =

>      libxl_device_nic_init(nic);
>  =

> -    tmp =3D xs_read(ctx->xsh, XBT_NULL,
> -                  libxl__sprintf(gc, "%s/handle", be_path), &len);
> -    if ( tmp )
> +    rc =3D libxl__xs_read_checked(gc, XBT_NULL,
> +                                libxl__sprintf(gc, "%s/handle", be_path),
> +                                &tmp);
> +
> +    if ((rc =3D=3D 0) && strlen(tmp))
>          nic->devid =3D atoi(tmp);
>      else
>          nic->devid =3D 0;
>  =

>      /* nic->mtu =3D */
>  =

> -    tmp =3D xs_read(ctx->xsh, XBT_NULL,
> -                  libxl__sprintf(gc, "%s/mac", be_path), &len);
> -    rc =3D libxl__parse_mac(tmp, nic->mac);
> -    if (rc)
> +    rc =3D libxl__xs_read_checked(gc, XBT_NULL,
> +                                libxl__sprintf(gc, "%s/mac", be_path),
> +                                &tmp);
> +
> +    if ((rc !=3D 0) || (strlen(tmp) =3D=3D 0) ||
> +        (libxl__parse_mac(tmp, nic->mac) !=3D 0))
>          memset(nic->mac, 0, sizeof(nic->mac));
>  =

>      nic->ip =3D xs_read(ctx->xsh, XBT_NULL,
> =