Re: [PATCH] tpm: fix potential NULL pointer access in tpm_del_char_device()

[Jarkko Sakkinen]

On Fri, 2021-09-10 at 20:04 +0200, Lino Sanfilippo wrote:
> In tpm_del_char_device() make sure that chip->ops is still valid.
> This check is needed since in case of a system shutdown
> tpm_class_shutdown() has already been called and set chip->ops to NULL.
> This leads to a NULL pointer access as soon as tpm_del_char_device()
> tries to access chip->ops in case of TPM 2.
> 
> Fixes: dcbeab1946454 ("tpm: fix crash in tpm_tis deinitialization")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Lino Sanfilippo <LinoSanfilippo@xxxxxx>
> ---

Have you been able to reproduce this in some environment?

/Jarkko