Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 9 Feb 2021 09:36:53 -0400
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Lino Sanfilippo <l.sanfilippo@kunbus.com>
Cc:     James Bottomley <James.Bottomley@HansenPartnership.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Lino Sanfilippo <LinoSanfilippo@gmx.de>, peterhuewe@gmx.de,
        stefanb@linux.vnet.ibm.com, stable@vger.kernel.org,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 2/2] tpm: in tpm2_del_space check if ops pointer is
 still valid
Message-ID: <20210209133653.GC4718@ziepe.ca>
References: <1612482643-11796-1-git-send-email-LinoSanfilippo@gmx.de>
 <1612482643-11796-3-git-send-email-LinoSanfilippo@gmx.de>
 <7308e5e9f51501bd92cced8f28ff6130c976b3ed.camel@HansenPartnership.com>
 <YByrCnswkIlz1w1t@kernel.org>
 <ee4adfbb99273e1bdceca210bc1fa5f16a50c415.camel@HansenPartnership.com>
 <20210205172528.GP4718@ziepe.ca>
 <08ce58ab-3513-5d98-16a5-b197276f6bce@kunbus.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <08ce58ab-3513-5d98-16a5-b197276f6bce@kunbus.com>
Precedence: bulk

On Tue, Feb 09, 2021 at 12:52:17PM +0100, Lino Sanfilippo wrote:
> > @@ -640,8 +643,10 @@ void tpm_chip_unregister(struct tpm_chip *chip)
> >  	if (IS_ENABLED(CONFIG_HW_RANDOM_TPM))
> >  		hwrng_unregister(&chip->hwrng);
> >  	tpm_bios_log_teardown(chip);
> > -	if (chip->flags & TPM_CHIP_FLAG_TPM2)
> > +	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
> >  		cdev_device_del(&chip->cdevs, &chip->devs);
> > +		put_device(&chip->devs);
> > +	}
> >  	tpm_del_char_device(chip);
> >  }
> >  EXPORT_SYMBOL_GPL(tpm_chip_unregister);
> > 
> 
> I tested the solution you scetched and it fixes the issue for me. Will you send a (real) patch for this?

No, feel free to bundle this up with any fixes needed and send it with
a Signed-off-by from both of us

I did it pretty fast so it will need a careful read that there isn't a
typo

Thanks,
Jason