From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752526AbdEEWip (ORCPT ); Fri, 5 May 2017 18:38:45 -0400 Received: from mail-pf0-f178.google.com ([209.85.192.178]:36681 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751161AbdEEWin (ORCPT ); Fri, 5 May 2017 18:38:43 -0400 Date: Fri, 5 May 2017 15:38:41 -0700 From: Kees Cook To: netdev@vger.kernel.org Cc: Kalle Valo , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Daniel Micay Subject: [PATCH] ray_cs: Avoid reading past end of buffer Message-ID: <20170505223841.GA20367@beast> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using memcpy() from a buffer that is shorter than the length copied means the destination buffer is being filled with arbitrary data from the kernel rodata segment. In this case, the source was made longer, since it did not match the destination structure size. Additionally removes a needless cast. This was found with the future CONFIG_FORTIFY_SOURCE feature. Cc: Daniel Micay Signed-off-by: Kees Cook --- drivers/net/wireless/ray_cs.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ray_cs.c b/drivers/net/wireless/ray_cs.c index b94479441b0c..170cd504e8ff 100644 --- a/drivers/net/wireless/ray_cs.c +++ b/drivers/net/wireless/ray_cs.c @@ -247,7 +247,10 @@ static const UCHAR b4_default_startup_parms[] = { 0x04, 0x08, /* Noise gain, limit offset */ 0x28, 0x28, /* det rssi, med busy offsets */ 7, /* det sync thresh */ - 0, 2, 2 /* test mode, min, max */ + 0, 2, 2, /* test mode, min, max */ + 0, /* rx/tx delay */ + 0, 0, 0, 0, 0, 0, /* current BSS id */ + 0 /* hop set */ }; /*===========================================================================*/ @@ -597,7 +600,7 @@ static void init_startup_params(ray_dev_t *local) * a_beacon_period = hops a_beacon_period = KuS *//* 64ms = 010000 */ if (local->fw_ver == 0x55) { - memcpy((UCHAR *) &local->sparm.b4, b4_default_startup_parms, + memcpy(&local->sparm.b4, b4_default_startup_parms, sizeof(struct b4_startup_params)); /* Translate sane kus input values to old build 4/5 format */ /* i = hop time in uS truncated to 3 bytes */ -- 2.7.4 -- Kees Cook Pixel Security