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 A87B1C433F5 for ; Fri, 28 Jan 2022 10:32:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347890AbiA1Kcz (ORCPT ); Fri, 28 Jan 2022 05:32:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43906 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347878AbiA1Kcy (ORCPT ); Fri, 28 Jan 2022 05:32:54 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 58DDFC061747; Fri, 28 Jan 2022 02:32:54 -0800 (PST) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 7FA23471; Fri, 28 Jan 2022 11:32:51 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1643365971; bh=QVy9zl0W8jMMsuagrjFHi3f0S0j/21GAM2lTr0325W0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=OeUrFGsKU4F+E6XXqPJtoup86EbTlroJpYbUqeD5i+PX4+dXjEb7W9340/J4SIcHd T37s/gyVQQei5Dn+UprtOlaaFCdjISEtPNMZQVcYMGwPMcPQ+b26YTkac5DKDejO2u cEgyqZu4Auv8KCmFfYgT5K8vk6CnArkU8ZvSAVsI= Date: Fri, 28 Jan 2022 12:32:30 +0200 From: Laurent Pinchart To: Greg KH Cc: Zhou Qingyang , kjlu@umn.edu, Benoit Parrot , Mauro Carvalho Chehab , Hans Verkuil , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] media: ti-vpe: cal: Fix a NULL pointer dereference in cal_ctx_v4l2_init_formats() Message-ID: References: <20220124172001.62457-1-zhou1615@umn.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Greg, On Fri, Jan 28, 2022 at 11:19:36AM +0100, Greg KH wrote: > On Tue, Jan 25, 2022 at 01:20:01AM +0800, Zhou Qingyang wrote: > > In cal_ctx_v4l2_init_formats(), devm_kzalloc() is assigned to fw and there > > is a dereference of it after that, which could lead to NULL pointer > > dereference on failure of devm_kzalloc(). > > > > Fix this bug by adding a NULL check of ctx->active_fmt. > > > > This bug was found by a static analyzer. > > > > Builds with 'make allyesconfig' show no new warnings, > > and our static analyzer no longer warns about this code. > > > > Fixes: 7168155002cf ("media: ti-vpe: cal: Move format handling to cal.c and expose helpers") > > Signed-off-by: Zhou Qingyang > > -- > > The analysis employs differential checking to identify inconsistent > > security operations (e.g., checks or kfrees) between two code paths > > and confirms that the inconsistent operations are not recovered in the > > current function or the callers, so they constitute bugs. > > > > Note that, as a bug found by static analysis, it can be a false > > positive or hard to trigger. Multiple researchers have cross-reviewed > > the bug. > > > > drivers/media/platform/ti-vpe/cal-video.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/media/platform/ti-vpe/cal-video.c b/drivers/media/platform/ti-vpe/cal-video.c > > index 7799da1cc261..3e936a2ca36c 100644 > > --- a/drivers/media/platform/ti-vpe/cal-video.c > > +++ b/drivers/media/platform/ti-vpe/cal-video.c > > @@ -823,6 +823,9 @@ static int cal_ctx_v4l2_init_formats(struct cal_ctx *ctx) > > /* Enumerate sub device formats and enable all matching local formats */ > > ctx->active_fmt = devm_kcalloc(ctx->cal->dev, cal_num_formats, > > sizeof(*ctx->active_fmt), GFP_KERNEL); > > + if (!ctx->active_fmt) > > + return -ENOMEM; > > + > > ctx->num_active_fmt = 0; > > > > for (j = 0, i = 0; ; ++j) { > > As stated before, umn.edu is still not allowed to contribute to the > Linux kernel. Please work with your administration to resolve this > issue. I thought this had been resolved, my bad. I can drop the patch, but it fixes a real bug (although unlikely). Should I re-author this fix ? -- Regards, Laurent Pinchart