linux-kernel - Re: [PATCH v3 2/2] tpm: in tpm2_del_space check if ops pointer is still valid

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: <YBzq1trVOiBfxDVp@kroah.com>
Date:   Fri, 5 Feb 2021 07:51:02 +0100
From:   Greg KH <gregkh@...uxfoundation.org>
To:     Lino Sanfilippo <LinoSanfilippo@....de>
Cc:     peterhuewe@....de, jarkko@...nel.org, jgg@...pe.ca,
        stefanb@...ux.vnet.ibm.com, James.Bottomley@...senpartnership.com,
        stable@...r.kernel.org, linux-integrity@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Lino Sanfilippo <l.sanfilippo@...bus.com>
Subject: Re: [PATCH v3 2/2] tpm: in tpm2_del_space check if ops pointer is
 still valid

On Fri, Feb 05, 2021 at 12:50:43AM +0100, Lino Sanfilippo wrote:
> From: Lino Sanfilippo <l.sanfilippo@...bus.com>
> 
> In tpm2_del_space() chip->ops is used for flushing the sessions. However
> this function may be called after tpm_chip_unregister() which sets
> the chip->ops pointer to NULL.
> Avoid a possible NULL pointer dereference by checking if chip->ops is still
> valid before accessing it.
> 
> Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()")
> Signed-off-by: Lino Sanfilippo <l.sanfilippo@...bus.com>
> ---
>  drivers/char/tpm/tpm2-space.c | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>