RE: dell_smbios KASAN bug

From: Mario.Limonciello
Date: Mon Mar 25 2019 - 09:31:02 EST


> -----Original Message-----
> From: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Sent: Wednesday, March 20, 2019 2:14 PM
> To: Tom Zanussi
> Cc: Pali Rohár; Limonciello, Mario; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: dell_smbios KASAN bug
>
>
> [EXTERNAL EMAIL]
>
> On Wed, 20 Mar 2019 14:05:49 -0500
> Tom Zanussi <tzanussi@xxxxxxxxx> wrote:
>
> > On Wed, 2019-03-20 at 14:41 -0400, Steven Rostedt wrote:
> > > On Wed, 20 Mar 2019 13:29:20 -0500
> > > Tom Zanussi <tzanussi@xxxxxxxxx> wrote:
> > >
> > > > Hi,
> > > >
> > > > While looking into an unrelated problem, I hit this KASAN use-
> > > > after-
> > > > free warning, so thought I'd let you know.
> > > >
> > > > I have no idea how to fix it, but let me know if you need more
> > > > info.
> > > >
> > >
> > > Could you run with debug in the kernel command line, and see if you
> > > hit
> > > any failed messages from the dell_smbios_init() call?
> > >
> >
> > Not much, but this looks relevant:
> >
> > [ 26.783749] dell_smbios: No SMBIOS backends available (wmi: -19,
> > smm: -19)
> > [ 26.963648] dell_smbios: No dell-smbios drivers are loaded
> >
>
> And does this fix you problem?
>
> -- Steve
>
> diff --git a/drivers/platform/x86/dell-smbios-base.c b/drivers/platform/x86/dell-
> smbios-base.c
> index 9dc282ed5a9e..c3825c674522 100644
> --- a/drivers/platform/x86/dell-smbios-base.c
> +++ b/drivers/platform/x86/dell-smbios-base.c
> @@ -619,6 +619,7 @@ static int __init dell_smbios_init(void)
>
> fail_platform_driver:
> kfree(da_tokens);
> + da_num_tokens = 0;
> return ret;
> }
>

Steven,

Since Tom confirmed this works will you send a formal patch to the ML with this fix?

Thanks,