Re: [Nouveau] [PATCH 1/9] drm/amd/pm: Annotate struct smu10_voltage_dependency_table with __counted_by
On Mon, Sep 25, 2023 at 1:52 PM Kees Cook wrote:
>
> On Mon, Sep 25, 2023 at 08:30:30AM +0200, Christian König wrote:
> > Am 22.09.23 um 19:41 schrieb Alex Deucher:
> > > On Fri, Sep 22, 2023 at 1:32 PM Kees Cook wrote:
> > > > Prepare for the coming implementation by GCC and Clang of the
> > > > __counted_by
> > > > attribute. Flexible array members annotated with __counted_by can have
> > > > their accesses bounds-checked at run-time checking via
> > > > CONFIG_UBSAN_BOUNDS
> > > > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> > > > functions).
> > > >
> > > > As found with Coccinelle[1], add __counted_by for struct
> > > > smu10_voltage_dependency_table.
> > > >
> > > > [1]
> > > > https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> > > >
> > > > Cc: Evan Quan
> > > > Cc: Alex Deucher
> > > > Cc: "Christian König"
> > > > Cc: "Pan, Xinhui"
> > > > Cc: David Airlie
> > > > Cc: Daniel Vetter
> > > > Cc: Xiaojian Du
> > > > Cc: Huang Rui
> > > > Cc: Kevin Wang
> > > > Cc: amd-...@lists.freedesktop.org
> > > > Cc: dri-de...@lists.freedesktop.org
> > > > Signed-off-by: Kees Cook
> > > Acked-by: Alex Deucher
> >
> > Mhm, I'm not sure if this is a good idea. That is a structure filled in by
> > the firmware, isn't it?
> >
> > That would imply that we might need to byte swap count before it is
> > checkable.
>
> The script found this instance because of this:
>
> static int smu10_get_clock_voltage_dependency_table(struct pp_hwmgr *hwmgr,
> struct smu10_voltage_dependency_table **pptable,
> uint32_t num_entry, const DpmClock_t
> *pclk_dependency_table)
> {
> uint32_t i;
> struct smu10_voltage_dependency_table *ptable;
>
> ptable = kzalloc(struct_size(ptable, entries, num_entry), GFP_KERNEL);
> if (NULL == ptable)
> return -ENOMEM;
>
> ptable->count = num_entry;
>
> So the implication is that it's native byte order... but you tell me! I
> certainly don't want this annotation if it's going to break stuff. :)
In this case, the code is for an integrated GPU in an x86 CPU so the
firmware and driver endianness match. You wouldn't find a stand alone
dGPU that uses this structure. In this case it's ok. False alarm.
Alex
Re: [Nouveau] [PATCH 1/9] drm/amd/pm: Annotate struct smu10_voltage_dependency_table with __counted_by
On Mon, Sep 25, 2023 at 08:30:30AM +0200, Christian König wrote:
> Am 22.09.23 um 19:41 schrieb Alex Deucher:
> > On Fri, Sep 22, 2023 at 1:32 PM Kees Cook wrote:
> > > Prepare for the coming implementation by GCC and Clang of the __counted_by
> > > attribute. Flexible array members annotated with __counted_by can have
> > > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
> > > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> > > functions).
> > >
> > > As found with Coccinelle[1], add __counted_by for struct
> > > smu10_voltage_dependency_table.
> > >
> > > [1]
> > > https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> > >
> > > Cc: Evan Quan
> > > Cc: Alex Deucher
> > > Cc: "Christian König"
> > > Cc: "Pan, Xinhui"
> > > Cc: David Airlie
> > > Cc: Daniel Vetter
> > > Cc: Xiaojian Du
> > > Cc: Huang Rui
> > > Cc: Kevin Wang
> > > Cc: amd-...@lists.freedesktop.org
> > > Cc: dri-de...@lists.freedesktop.org
> > > Signed-off-by: Kees Cook
> > Acked-by: Alex Deucher
>
> Mhm, I'm not sure if this is a good idea. That is a structure filled in by
> the firmware, isn't it?
>
> That would imply that we might need to byte swap count before it is
> checkable.
The script found this instance because of this:
static int smu10_get_clock_voltage_dependency_table(struct pp_hwmgr *hwmgr,
struct smu10_voltage_dependency_table **pptable,
uint32_t num_entry, const DpmClock_t
*pclk_dependency_table)
{
uint32_t i;
struct smu10_voltage_dependency_table *ptable;
ptable = kzalloc(struct_size(ptable, entries, num_entry), GFP_KERNEL);
if (NULL == ptable)
return -ENOMEM;
ptable->count = num_entry;
So the implication is that it's native byte order... but you tell me! I
certainly don't want this annotation if it's going to break stuff. :)
--
Kees Cook
Re: [Nouveau] [PATCH 1/9] drm/amd/pm: Annotate struct smu10_voltage_dependency_table with __counted_by
On Mon, Sep 25, 2023 at 10:07 AM Alex Deucher wrote:
>
> On Mon, Sep 25, 2023 at 2:30 AM Christian König
> wrote:
> >
> > Am 22.09.23 um 19:41 schrieb Alex Deucher:
> > > On Fri, Sep 22, 2023 at 1:32 PM Kees Cook wrote:
> > >> Prepare for the coming implementation by GCC and Clang of the
> > >> __counted_by
> > >> attribute. Flexible array members annotated with __counted_by can have
> > >> their accesses bounds-checked at run-time checking via
> > >> CONFIG_UBSAN_BOUNDS
> > >> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> > >> functions).
> > >>
> > >> As found with Coccinelle[1], add __counted_by for struct
> > >> smu10_voltage_dependency_table.
> > >>
> > >> [1]
> > >> https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> > >>
> > >> Cc: Evan Quan
> > >> Cc: Alex Deucher
> > >> Cc: "Christian König"
> > >> Cc: "Pan, Xinhui"
> > >> Cc: David Airlie
> > >> Cc: Daniel Vetter
> > >> Cc: Xiaojian Du
> > >> Cc: Huang Rui
> > >> Cc: Kevin Wang
> > >> Cc: amd-...@lists.freedesktop.org
> > >> Cc: dri-de...@lists.freedesktop.org
> > >> Signed-off-by: Kees Cook
> > > Acked-by: Alex Deucher
> >
> > Mhm, I'm not sure if this is a good idea. That is a structure filled in
> > by the firmware, isn't it?
> >
> > That would imply that we might need to byte swap count before it is
> > checkable.
>
> True. Good point. Same for the other amdgpu patch.
Actually the other patch is fine. That's just a local structure.
Alex
>
> Alex
>
> >
> > Regards,
> > Christian.
> >
> > >
> > >> ---
> > >> drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h | 2 +-
> > >> 1 file changed, 1 insertion(+), 1 deletion(-)
> > >>
> > >> diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
> > >> b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
> > >> index 808e0ecbe1f0..42adc2a3dcbc 100644
> > >> --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
> > >> +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
> > >> @@ -192,7 +192,7 @@ struct smu10_clock_voltage_dependency_record {
> > >>
> > >> struct smu10_voltage_dependency_table {
> > >> uint32_t count;
> > >> - struct smu10_clock_voltage_dependency_record entries[];
> > >> + struct smu10_clock_voltage_dependency_record entries[]
> > >> __counted_by(count);
> > >> };
> > >>
> > >> struct smu10_clock_voltage_information {
> > >> --
> > >> 2.34.1
> > >>
> >
Re: [Nouveau] [PATCH 1/9] drm/amd/pm: Annotate struct smu10_voltage_dependency_table with __counted_by
On 9/22/23 11:32, Kees Cook wrote:
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct
smu10_voltage_dependency_table.
[1]
https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Evan Quan
Cc: Alex Deucher
Cc: "Christian König"
Cc: "Pan, Xinhui"
Cc: David Airlie
Cc: Daniel Vetter
Cc: Xiaojian Du
Cc: Huang Rui
Cc: Kevin Wang
Cc: amd-...@lists.freedesktop.org
Cc: dri-de...@lists.freedesktop.org
Signed-off-by: Kees Cook
Reviewed-by: Gustavo A. R. Silva
Thanks
--
Gustavo
---
drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
index 808e0ecbe1f0..42adc2a3dcbc 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu10_hwmgr.h
@@ -192,7 +192,7 @@ struct smu10_clock_voltage_dependency_record {
struct smu10_voltage_dependency_table {
uint32_t count;
- struct smu10_clock_voltage_dependency_record entries[];
+ struct smu10_clock_voltage_dependency_record entries[]
__counted_by(count);
};
struct smu10_clock_voltage_information {
