From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26DFDC4332E for ; Fri, 5 Mar 2021 12:39:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA07364EE8 for ; Fri, 5 Mar 2021 12:39:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233206AbhCEMjb (ORCPT ); Fri, 5 Mar 2021 07:39:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:53024 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232041AbhCEMi6 (ORCPT ); Fri, 5 Mar 2021 07:38:58 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3774664FF0; Fri, 5 Mar 2021 12:38:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614947937; bh=ten8VZA0HMjTVB4OJBxb18K57bDdXHdD+HdxiunCSFI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j7uIw1N5eZSzNip37Nug+Fuqq4AfZy3Q8rpYLU1N0dKHh3bUZR0OD4B3sTkssRY1x VoSkUYYhCbdfV5+BGut2AzO85HKaveHdy0xMCUzf6Xs9AV6OTWHDZ097y+3Ifk+nnm p+mbGsLlNZ82UcuP/QR43leOFw7zSUPJHrv/V9qo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+6d31bf169a8265204b8d@syzkaller.appspotmail.com, Sean Young , Mauro Carvalho Chehab Subject: [PATCH 4.14 12/39] media: mceusb: sanity check for prescaler value Date: Fri, 5 Mar 2021 13:22:11 +0100 Message-Id: <20210305120852.379092766@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210305120851.751937389@linuxfoundation.org> References: <20210305120851.751937389@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sean Young commit 9dec0f48a75e0dadca498002d25ef4e143e60194 upstream. prescaler larger than 8 would mean the carrier is at most 152Hz, which does not make sense for IR carriers. Reported-by: syzbot+6d31bf169a8265204b8d@syzkaller.appspotmail.com Signed-off-by: Sean Young Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/rc/mceusb.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/drivers/media/rc/mceusb.c +++ b/drivers/media/rc/mceusb.c @@ -630,11 +630,18 @@ static void mceusb_dev_printdata(struct data[0], data[1]); break; case MCE_RSP_EQIRCFS: + if (!data[0] && !data[1]) { + dev_dbg(dev, "%s: no carrier", inout); + break; + } + // prescaler should make sense + if (data[0] > 8) + break; period = DIV_ROUND_CLOSEST((1U << data[0] * 2) * (data[1] + 1), 10); if (!period) break; - carrier = (1000 * 1000) / period; + carrier = USEC_PER_SEC / period; dev_dbg(dev, "%s carrier of %u Hz (period %uus)", inout, carrier, period); break;