Re: [tpmdd-devel] [PATCH] tpm_crb: fix bad name pointer usage with struct resource

[Jarkko Sakkinen]

On Wed, Feb 17, 2016 at 11:36:23AM +0200, Jarkko Sakkinen wrote:
> On Tue, Feb 16, 2016 at 09:52:19PM -0700, Jason Gunthorpe wrote:
> > On Wed, Feb 17, 2016 at 02:27:54AM +0200, Jarkko Sakkinen wrote:
> > > -	if (acpi_dev_resource_memory(ares, &res))
> > > +	if (acpi_dev_resource_memory(ares, &res)) {
> > > +		res.name = NULL;
> > 
> > What? How is this not a bug in acpi_dev_resource_memory? Maybe it
> > needs to memcpy into devm allocated memory instead, but I'm confused
> > how/why/when acpi could free name.
> > 
> > The same code exists in tpm_tis as well.
> 
> That was the only way to fix the garbage issue. I would keep things
> this way for Linux 4.5.

Hmm... Interesting with the machine where I have dTPM:

$ cat /proc/iomem|grep -A2 MSFT
fed40000-fed44fff : MSFT0101:00
  fed40000-fed44fff : 

Just an empty string.

Maybe for the release the safest bet would be anyway explicitly not
use the name field? That's the safest bet given the release time
frame.

/Jarkko