linux-kernel - Re: [PATCH] usb: typec: ucsi: Handle incorrect num

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <2025092909-sacrifice-immortal-5e5d@gregkh>
Date: Mon, 29 Sep 2025 21:35:25 +0200
From: Greg KH <gregkh@...uxfoundation.org>
To: Mark Pearson <mpearson-lenovo@...ebb.ca>
Cc: Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
	linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] usb: typec: ucsi: Handle incorrect num_connectors
 capability

On Mon, Sep 29, 2025 at 03:25:06PM -0400, Mark Pearson wrote:
> Hi Heikki,
> 
> On Mon, Sep 22, 2025, at 8:48 AM, Heikki Krogerus wrote:
> > On Fri, Sep 19, 2025 at 11:45:48AM -0400, Mark Pearson wrote:
> >> Hi Heikki,
> >> 
> >> On Fri, Sep 19, 2025, at 3:44 AM, Heikki Krogerus wrote:
> >> > On Thu, Sep 18, 2025 at 09:50:30AM +0200, Greg KH wrote:
> >> >> On Wed, Sep 17, 2025 at 02:14:28PM -0400, Mark Pearson wrote:
> >> >> > Hi all,
> >> >> > 
> >> >> > On Fri, Aug 22, 2025, at 8:54 AM, Mark Pearson wrote:
> >> >> > > Hi Greg,
> >> >> > >
> >> >> > > On Fri, Aug 22, 2025, at 12:51 AM, Greg KH wrote:
> >> >> > >> On Thu, Aug 21, 2025 at 02:53:07PM -0400, Mark Pearson wrote:
> >> >> > >>> The UCSI spec states that the num_connectors field is 7 bits, and the
> >> >> > >>> 8th bit is reserved and should be set to zero.
> >> >> > >>> Some buggy FW has been known to set this bit, and it can lead to a
> >> >> > >>> system not booting.
> >> >> > >>> Flag that the FW is not behaving correctly, and auto-fix the value
> >> >> > >>> so that the system boots correctly.
> >> >> > >>> 
> >> >> > >>> Found on Lenovo P1 G8 during Linux enablement program. The FW will
> >> >> > >>> be fixed, but seemed worth addressing in case it hit platforms that
> >> >> > >>> aren't officially Linux supported.
> >> >> > >>> 
> >> >> > >>> Signed-off-by: Mark Pearson <mpearson-lenovo@...ebb.ca>
> >> >> > >>
> >> >> > >> Any hints as to what commit id this fixes?
> >> >> > >>
> >> >> > >> thanks,
> >> >> > >>
> >> >> > >> greg k-h
> >> >> > >
> >> >> > > Maybe 3cf657f ('Remove all bit-fields')?
> >> >> > >
> >> >> > > The commit there states that 'We can't use bit fields with data that is 
> >> >> > > received or send
> >> >> > > to/from the device.'
> >> >> > > Not sure why that is, but I assumed this means we shouldn't change the 
> >> >> > > structure to use 7 bits for num_connectors, which was my original plan.
> >> >> > >
> >> >> > > After that, we go all the way back to the file creation (c1b0bc2) where 
> >> >> > > it was defined as 8 bit.
> >> >> > >
> >> >> > 
> >> >> > Just a gentle nudge to see if there are any concerns or questions with the patch.
> >> >> 
> >> >> I was waiting for the maintainer of this code to review it :)
> >> >
> >> > So not Fixes tag?
> >> >
> >> 
> >> I can add a Fixes tag for the very original commit of this file (c1b0bc2) if that's wanted.
> >
> > I don't think it's necessary in this case if the fw is really fixed.
> > But what says Greg?
> >
> I don't think the Fixes tag makes sense either; and to confirm - this will be fixed in FW.
> 
> Greg - can we go ahead with this please?

It's the merge window right now, I'll pick it up after -rc1 is out.

thanks,

greg k-h