From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf0-f170.google.com ([209.85.192.170]:33863 "EHLO mail-pf0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751264AbdEEWin (ORCPT ); Fri, 5 May 2017 18:38:43 -0400 Received: by mail-pf0-f170.google.com with SMTP id e64so8527265pfd.1 for ; Fri, 05 May 2017 15:38:43 -0700 (PDT) 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> (sfid-20170506_003909_610564_7BE71E5B) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: 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