Re: [PATCH v3 0/4] Fix multiple race condition vulnerabilities in dvb-core and device driver

From: Lee Jones <lee@kernel.org>
To: Takashi Iwai <tiwai@suse.de>
Cc: Hyunwoo Kim <imv4bel@gmail.com>,
	mchehab@kernel.org, kernel@tuxforce.de,
	linux-media@vger.kernel.org, linux-usb@vger.kernel.org,
	cai.huoqing@linux.dev
Subject: Re: [PATCH v3 0/4] Fix multiple race condition vulnerabilities in dvb-core and device driver
Date: Tue, 28 Feb 2023 11:32:31 +0000	[thread overview]
Message-ID: <Y/3mT9uSsuviT+sa@google.com> (raw)
In-Reply-To: <Y/YXbNgBhhWhfjwS@google.com>

On Wed, 22 Feb 2023, Lee Jones wrote:

> On Tue, 10 Jan 2023, Takashi Iwai wrote:
> 
> > On Thu, 17 Nov 2022 05:59:21 +0100,
> > Hyunwoo Kim wrote:
> > > 
> > > Dear,
> > > 
> > > This patch set is a security patch for various race condition vulnerabilities that occur
> > > in 'dvb-core' and 'ttusb_dec', a dvb-based device driver.
> > > 
> > > 
> > > # 1. media: dvb-core: Fix use-after-free due to race condition occurring in dvb_frontend
> > > This is a security patch for a race condition that occurs in the dvb_frontend system of dvb-core.
> > > 
> > > The race condition that occurs here will occur with _any_ device driver using dvb_frontend.
> > > 
> > > The race conditions that occur in dvb_frontend are as follows
> 
> [...]
> 
> > > # 4. media: ttusb-dec: Fix memory leak in ttusb_dec_exit_dvb()
> > > This is a patch for a memory leak that occurs in the ttusb_dec_exit_dvb() function.
> > > 
> > > Because ttusb_dec_exit_dvb() does not call dvb_frontend_detach(),
> > > several fe related structures are not kfree()d.
> > > 
> > > Users can trigger a memory leak just by repeating connecting and disconnecting
> > > the ttusb_dec device.
> > > 
> > > 
> > > Finally, most of these patches are similar to this one, the security patch for
> > > CVE-2022-41218 that I reported:
> > > https://lore.kernel.org/linux-media/20221031100245.23702-1-tiwai@suse.de/
> > > 
> > > 
> > > Regards,
> > > Hyunwoo Kim
> > 
> > Are those issues still seen with the latest 6.2-rc kernel?
> > I'm asking because there have been a few fixes in dvb-core to deal
> > with some UAFs.
> > 
> > BTW, Mauro, the issues are tagged with several CVE's:
> > CVE-2022-45884, CVE-2022-45886, CVE-2022-45885, CVE-2022-45887.
> 
> Was there an answer to this question?
> 
> Rightly or wrongly this patch is still being touted as the fix for some
> reported CVEs [0].
> 
> Is this patch still required or has it been superseded?  If the later,
> which patch superseded it?
> 
> Thanks.
> 
> [0] https://nvd.nist.gov/vuln/detail/CVE-2022-45886

Have these issues been fixed already?

If not, is this patch set due to be merged or reviewed?

-- 
Lee Jones [李琼斯]