From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chen Gang Subject: [PATCH] net: irda: using kzalloc() instead of kmalloc() to avoid strncpy() issue. Date: Fri, 17 May 2013 17:13:04 +0800 Message-ID: <5195F4A0.3000708@asianux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: David Miller , netdev To: samuel@sortiz.org Return-path: Received: from intranet.asianux.com ([58.214.24.6]:46157 "EHLO intranet.asianux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751449Ab3EQJOD (ORCPT ); Fri, 17 May 2013 05:14:03 -0400 Sender: netdev-owner@vger.kernel.org List-ID: 'discovery->data.info' length is 22, NICKNAME_MAX_LEN is 21, so the strncpy() will always left the last byte of 'discovery->data.info' uninitialized. When 'text' length is longer than 21 (NICKNAME_MAX_LEN), if still left the last byte of 'discovery->data.info' uninitialized, the next strlen() will cause issue. Also 'discovery->data' is 'struct irda_device_info' which defined in "include/uapi/...", it may copy to user mode, so need whole initialized. All together, need use kzalloc() instead of kmalloc() to initialize all members firstly. Signed-off-by: Chen Gang --- net/irda/irlap_frame.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/irda/irlap_frame.c b/net/irda/irlap_frame.c index 8c00416..9ea0c93 100644 --- a/net/irda/irlap_frame.c +++ b/net/irda/irlap_frame.c @@ -544,7 +544,7 @@ static void irlap_recv_discovery_xid_cmd(struct irlap_cb *self, /* * We now have some discovery info to deliver! */ - discovery = kmalloc(sizeof(discovery_t), GFP_ATOMIC); + discovery = kzalloc(sizeof(discovery_t), GFP_ATOMIC); if (!discovery) { IRDA_WARNING("%s: unable to malloc!\n", __func__); return; -- 1.7.7.6