Re: [PATCH] tee: optee: Fix kernel panic caused by incorrect error handling

[Jens Wiklander]

Hi,

On Mon, Mar 4, 2024 at 6:45 AM Sumit Garg <sumit.garg@xxxxxxxxxx> wrote:
>
> + Arnd
>
> On Fri, 1 Mar 2024 at 20:07, Sumit Garg <sumit.garg@xxxxxxxxxx> wrote:
> >
> > The error path while failing to register devices on the TEE bus has a
> > bug leading to kernel panic as follows:
> >
> > [   15.398930] Unable to handle kernel paging request at virtual address ffff07ed00626d7c
> > [   15.406913] Mem abort info:
> > [   15.409722]   ESR = 0x0000000096000005
> > [   15.413490]   EC = 0x25: DABT (current EL), IL = 32 bits
> > [   15.418814]   SET = 0, FnV = 0
> > [   15.421878]   EA = 0, S1PTW = 0
> > [   15.425031]   FSC = 0x05: level 1 translation fault
> > [   15.429922] Data abort info:
> > [   15.432813]   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
> > [   15.438310]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
> > [   15.443372]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> > [   15.448697] swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000d9e3e000
> > [   15.455413] [ffff07ed00626d7c] pgd=1800000bffdf9003, p4d=1800000bffdf9003, pud=0000000000000000
> > [   15.464146] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
> >
> > Commit 7269cba53d90 ("tee: optee: Fix supplicant based device enumeration")
> > lead to the introduction of this bug. So fix it appropriately.
> >
> > Reported-by: Mikko Rapeli <mikko.rapeli@xxxxxxxxxx>
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218542
> > Fixes: 7269cba53d90 ("tee: optee: Fix supplicant based device enumeration")
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx>
> > ---
> >  drivers/tee/optee/device.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
>
> Jens, Arnd,
>
> Is there any chance for this fix to make it into v6.8 release?

I'm picking up this and have also just sent it in a pull request for
v6.8. If it makes it into v6.8 remains to be seen.

Thanks,
Jens

>
> -Sumit
>
> > diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c
> > index 9d2afac96acc..d296c70ddfdc 100644
> > --- a/drivers/tee/optee/device.c
> > +++ b/drivers/tee/optee/device.c
> > @@ -90,13 +90,14 @@ static int optee_register_device(const uuid_t *device_uuid, u32 func)
> >         if (rc) {
> >                 pr_err("device registration failed, err: %d\n", rc);
> >                 put_device(&optee_device->dev);
> > +               return rc;
> >         }
> >
> >         if (func == PTA_CMD_GET_DEVICES_SUPP)
> >                 device_create_file(&optee_device->dev,
> >                                    &dev_attr_need_supplicant);
> >
> > -       return rc;
> > +       return 0;
> >  }
> >
> >  static int __optee_enumerate_devices(u32 func)
> > --
> > 2.34.1
> >