If the value read from the CHDBOFF and ERDBOFF registers is outside the
range of the MHI register space then an invalid address might be computed
which later causes a kernel panic. Range check the read value to prevent
a crash due to bad data from the device.
Fixes: 6cd330ae76ff ("bus: mhi: core: Add support for ringing channel/event ring doorbells")
Signed-off-by: Jeffrey Hugo <[email protected]>
Reviewed-by: Pranjal Ramajor Asha Kanojiya <[email protected]>
---
drivers/bus/mhi/host/init.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
index 3d779ee..ae8ebcfb 100644
--- a/drivers/bus/mhi/host/init.c
+++ b/drivers/bus/mhi/host/init.c
@@ -516,6 +516,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
return -EIO;
}
+ if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
+ dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
+ val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB));
+ return -EINVAL;
+ }
+
/* Setup wake db */
mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
mhi_cntrl->wake_set = false;
@@ -532,6 +538,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
return -EIO;
}
+ if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) {
+ dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n",
+ val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings));
+ return -EINVAL;
+ }
+
/* Setup event db address for each ev_ring */
mhi_event = mhi_cntrl->mhi_event;
for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
--
2.7.4
On Fri, Mar 17, 2023 at 09:14:19AM -0600, Jeffrey Hugo wrote:
> If the value read from the CHDBOFF and ERDBOFF registers is outside the
> range of the MHI register space then an invalid address might be computed
> which later causes a kernel panic. Range check the read value to prevent
> a crash due to bad data from the device.
>
> Fixes: 6cd330ae76ff ("bus: mhi: core: Add support for ringing channel/event ring doorbells")
Please CC stable list.
> Signed-off-by: Jeffrey Hugo <[email protected]>
> Reviewed-by: Pranjal Ramajor Asha Kanojiya <[email protected]>
> ---
> drivers/bus/mhi/host/init.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
> index 3d779ee..ae8ebcfb 100644
> --- a/drivers/bus/mhi/host/init.c
> +++ b/drivers/bus/mhi/host/init.c
> @@ -516,6 +516,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
> return -EIO;
> }
>
> + if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
> + dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
> + val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB));
> + return -EINVAL;
Isn't -ERANGE a better errno here and also in other places of the driver?
Thanks,
Mani
> + }
> +
> /* Setup wake db */
> mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
> mhi_cntrl->wake_set = false;
> @@ -532,6 +538,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
> return -EIO;
> }
>
> + if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) {
> + dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n",
> + val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings));
> + return -EINVAL;
> + }
> +
> /* Setup event db address for each ev_ring */
> mhi_event = mhi_cntrl->mhi_event;
> for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
> --
> 2.7.4
>
>
--
மணிவண்ணன் சதாசிவம்
On 3/24/2023 4:34 AM, Manivannan Sadhasivam wrote:
> On Fri, Mar 17, 2023 at 09:14:19AM -0600, Jeffrey Hugo wrote:
>> If the value read from the CHDBOFF and ERDBOFF registers is outside the
>> range of the MHI register space then an invalid address might be computed
>> which later causes a kernel panic. Range check the read value to prevent
>> a crash due to bad data from the device.
>>
>> Fixes: 6cd330ae76ff ("bus: mhi: core: Add support for ringing channel/event ring doorbells")
>
> Please CC stable list.
The stable folks have been automatically picking up everything with a
fixes tag for years. CCing the stable list does not seem to do anything
unless the patch needs specific backporting adjustments.
Do you still want an explicit CC?
>
>> Signed-off-by: Jeffrey Hugo <[email protected]>
>> Reviewed-by: Pranjal Ramajor Asha Kanojiya <[email protected]>
>> ---
>> drivers/bus/mhi/host/init.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>>
>> diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
>> index 3d779ee..ae8ebcfb 100644
>> --- a/drivers/bus/mhi/host/init.c
>> +++ b/drivers/bus/mhi/host/init.c
>> @@ -516,6 +516,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
>> return -EIO;
>> }
>>
>> + if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
>> + dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
>> + val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB));
>> + return -EINVAL;
>
> Isn't -ERANGE a better errno here and also in other places of the driver?
I suppose that could work. This was modeled after the existing BHI (eg
BHIOFF) range checks. You want those updated in the same change or a
separate one?
> Thanks,
> Mani
>
>> + }
>> +
>> /* Setup wake db */
>> mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
>> mhi_cntrl->wake_set = false;
>> @@ -532,6 +538,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
>> return -EIO;
>> }
>>
>> + if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) {
>> + dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n",
>> + val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings));
>> + return -EINVAL;
>> + }
>> +
>> /* Setup event db address for each ev_ring */
>> mhi_event = mhi_cntrl->mhi_event;
>> for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
>> --
>> 2.7.4
>>
>>
>
On Fri, Mar 24, 2023 at 07:50:01AM -0600, Jeffrey Hugo wrote:
> On 3/24/2023 4:34 AM, Manivannan Sadhasivam wrote:
> > On Fri, Mar 17, 2023 at 09:14:19AM -0600, Jeffrey Hugo wrote:
> > > If the value read from the CHDBOFF and ERDBOFF registers is outside the
> > > range of the MHI register space then an invalid address might be computed
> > > which later causes a kernel panic. Range check the read value to prevent
> > > a crash due to bad data from the device.
> > >
> > > Fixes: 6cd330ae76ff ("bus: mhi: core: Add support for ringing channel/event ring doorbells")
> >
> > Please CC stable list.
>
> The stable folks have been automatically picking up everything with a fixes
> tag for years. CCing the stable list does not seem to do anything unless
> the patch needs specific backporting adjustments.
>
> Do you still want an explicit CC?
>
That was the impression I had but Greg wanted us to explicitly CC stable list
and add a hint about how deep the patch needs to be applied.
> >
> > > Signed-off-by: Jeffrey Hugo <[email protected]>
> > > Reviewed-by: Pranjal Ramajor Asha Kanojiya <[email protected]>
> > > ---
> > > drivers/bus/mhi/host/init.c | 12 ++++++++++++
> > > 1 file changed, 12 insertions(+)
> > >
> > > diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
> > > index 3d779ee..ae8ebcfb 100644
> > > --- a/drivers/bus/mhi/host/init.c
> > > +++ b/drivers/bus/mhi/host/init.c
> > > @@ -516,6 +516,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
> > > return -EIO;
> > > }
> > > + if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) {
> > > + dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n",
> > > + val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB));
> > > + return -EINVAL;
> >
> > Isn't -ERANGE a better errno here and also in other places of the driver?
>
> I suppose that could work. This was modeled after the existing BHI (eg
> BHIOFF) range checks. You want those updated in the same change or a
> separate one?
>
That can go into a separate change.
Thanks,
Mani
> > Thanks,
> > Mani
> >
> > > + }
> > > +
> > > /* Setup wake db */
> > > mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB);
> > > mhi_cntrl->wake_set = false;
> > > @@ -532,6 +538,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl)
> > > return -EIO;
> > > }
> > > + if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) {
> > > + dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n",
> > > + val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings));
> > > + return -EINVAL;
> > > + }
> > > +
> > > /* Setup event db address for each ev_ring */
> > > mhi_event = mhi_cntrl->mhi_event;
> > > for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) {
> > > --
> > > 2.7.4
> > >
> > >
> >
>
--
மணிவண்ணன் சதாசிவம்