From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752219AbbI3AKh (ORCPT ); Tue, 29 Sep 2015 20:10:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36357 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751309AbbI3AKf (ORCPT ); Tue, 29 Sep 2015 20:10:35 -0400 From: Laura Abbott To: Antti Palosaari , Mauro Carvalho Chehab Cc: Laura Abbott , Olli Salonen , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Stuart Auchterlonie , stable@kernel.org Subject: [PATCH 1/2] si2168: Bounds check firmware Date: Tue, 29 Sep 2015 17:10:09 -0700 Message-Id: <1443571810-5627-1-git-send-email-labbott@fedoraproject.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When reading the firmware and sending commands, the length must be bounds checked to avoid overrunning the size of the command buffer and smashing the stack if the firmware is not in the expected format: si2168 11-0064: found a 'Silicon Labs Si2168-B40' si2168 11-0064: downloading firmware from file 'dvb-demod-si2168-b40-01.fw' si2168 11-0064: firmware download failed -95 Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffffa085708f Add the proper check. Cc: stable@kernel.org Reported-by: Stuart Auchterlonie Reviewed-by: Antti Palosaari Signed-off-by: Laura Abbott --- drivers/media/dvb-frontends/si2168.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c index 81788c5..821a8f4 100644 --- a/drivers/media/dvb-frontends/si2168.c +++ b/drivers/media/dvb-frontends/si2168.c @@ -502,6 +502,10 @@ static int si2168_init(struct dvb_frontend *fe) /* firmware is in the new format */ for (remaining = fw->size; remaining > 0; remaining -= 17) { len = fw->data[fw->size - remaining]; + if (len > SI2168_ARGLEN) { + ret = -EINVAL; + break; + } memcpy(cmd.args, &fw->data[(fw->size - remaining) + 1], len); cmd.wlen = len; cmd.rlen = 1; -- 2.4.3