From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: [Patch v3 3/4] tools/libxl: Fix libxl__device_nic_from_xs_be() Date: Mon, 25 Nov 2013 20:49:27 +0000 Message-ID: <1385412567-7717-1-git-send-email-andrew.cooper3@citrix.com> References: <52939C67.7020108@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <52939C67.7020108@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Xen-devel Cc: Andrew Cooper , Ian Jackson , Ian Campbell , Roger Pau Monne List-Id: xen-devel@lists.xenproject.org Coverity ID: 1055886 Replace uses of xs_read() with libxl__xs_read_checked() which appropriately garbage-collects the allocated string, and avoid executing libxl__parse_mac(NULL,) if the second xenstore read fails. Signed-off-by: Andrew Cooper CC: Ian Campbell CC: Ian Jackson CC: Roger Pau Monne --- 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__gc *gc, { libxl_ctx *ctx = libxl__gc_owner(gc); unsigned int len; - char *tmp; + const char *tmp; int rc; libxl_device_nic_init(nic); - tmp = xs_read(ctx->xsh, XBT_NULL, - libxl__sprintf(gc, "%s/handle", be_path), &len); - if ( tmp ) + rc = libxl__xs_read_checked(gc, XBT_NULL, + libxl__sprintf(gc, "%s/handle", be_path), + &tmp); + + if ((rc == 0) && strlen(tmp)) nic->devid = atoi(tmp); else nic->devid = 0; /* nic->mtu = */ - tmp = xs_read(ctx->xsh, XBT_NULL, - libxl__sprintf(gc, "%s/mac", be_path), &len); - rc = libxl__parse_mac(tmp, nic->mac); - if (rc) + rc = libxl__xs_read_checked(gc, XBT_NULL, + libxl__sprintf(gc, "%s/mac", be_path), + &tmp); + + if ((rc != 0) || (strlen(tmp) == 0) || + (libxl__parse_mac(tmp, nic->mac) != 0)) memset(nic->mac, 0, sizeof(nic->mac)); nic->ip = xs_read(ctx->xsh, XBT_NULL, -- 1.7.10.4