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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A519BEE49B7 for ; Thu, 24 Aug 2023 11:47:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241174AbjHXLrY (ORCPT ); Thu, 24 Aug 2023 07:47:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40546 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241184AbjHXLrE (ORCPT ); Thu, 24 Aug 2023 07:47:04 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BD0B1736; Thu, 24 Aug 2023 04:47:03 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9D957641B6; Thu, 24 Aug 2023 11:47:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9C23DC433CD; Thu, 24 Aug 2023 11:47:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1692877622; bh=ujlrD4Sp8quQd5NmAy54IKaq5mtGExATpmzJqrhMpfo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SZASipakVIkRDiJc9gemQoyx1PJon9fy172p5VL6liXqmP2xTcHuiMEaVLnpZM222 QPHoiHVcCWNmAuEPE1k6EBija3gacj7Jaf1+PBHgLUTcS0nZhbe7UG9fNdMreflVz8 QKdJF5+dZSEbxZMA1xZ0bnnrMPD7OEgS614eN7hM= Date: Thu, 24 Aug 2023 13:46:59 +0200 From: Greg KH To: coolrrsh@gmail.com Cc: hverkuil@xs4all.nl, mchehab@kernel.org, slark_xiao@163.com, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org, syzbot+e27f3dbdab04e43b9f73@syzkaller.appspotmail.com Subject: Re: [PATCH v3] media: gspca: UBSAN: shift-out-of-bounds in set_flicker Message-ID: <2023082406-vascular-unroasted-077a@gregkh> References: <20230824085731.9930-1-coolrrsh@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230824085731.9930-1-coolrrsh@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 24, 2023 at 02:27:31PM +0530, coolrrsh@gmail.com wrote: > From: Rajeshwar R Shinde > > Syzkaller reported the following issue: > > UBSAN: shift-out-of-bounds in drivers/media/usb/gspca/cpia1.c:1031:27 > shift exponent 245 is too large for 32-bit type 'int' > > When the value of the variable "sd->params.exposure.gain" exceeds the > number of bits in an int, a shift-out-of-bounds error occurs. The error is > generated when the variable "currentexp" is left-shifted by more than 31 > bits. In order to confirm the range is valid, the conditional expression > was added. > > Reported-by: syzbot+e27f3dbdab04e43b9f73@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/all/20230818164522.12806-1-coolrrsh@gmail.com > Link: https://syzkaller.appspot.com/bug?extid=e27f3dbdab04e43b9f73 > Signed-off-by: Rajeshwar R Shinde You have loads of trailing whitespace, please fix your editor to not do that. > --- > v1->v2 > Changed the patch In what way? Be specific. > v2->v3 > Changed the commit message Again, be specific please. Otherwise all changes could be listed with these two sentances and that helps none of us out :( > --- > drivers/media/usb/gspca/cpia1.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/media/usb/gspca/cpia1.c b/drivers/media/usb/gspca/cpia1.c > index 46ed95483e22..dafc522d5e7b 100644 > --- a/drivers/media/usb/gspca/cpia1.c > +++ b/drivers/media/usb/gspca/cpia1.c > @@ -1028,6 +1028,8 @@ static int set_flicker(struct gspca_dev *gspca_dev, int on, int apply) > sd->params.exposure.expMode = 2; > sd->exposure_status = EXPOSURE_NORMAL; > } > + if (sd->params.exposure.gain > 31) > + return -1; Why is this still -1? greg k-h