Re: [PATCH-next] Fix unintentional integer overflow

[Advait Dhamorikar]

Hi Sathish,

> Please collate the changes together with Lijo's suggestion as well,
> "1ULL <<" instead of typecast, there are 3 occurrences of the error in
> f0b19b84d391.

I could only observe two instances of this error in f0b19b84d391 at:
'mask = (1 << (adev->jpeg.num_jpeg_inst * adev->jpeg.num_jpeg_rings)) - 1;`
and `mask |= 1 << ((i * adev->jpeg.num_jpeg_rings) + j);`

There are a few instances where we can use 1U instead of int as
harvest_config uses unsigned int
(adev->jpeg.harvest_config & (1 << i)
However I think they should be fixed in a separate patch?

Thanks and regards,
Advait

On Sat, 5 Oct 2024 at 09:05, Sundararaju, Sathishkumar <sasundar@xxxxxxx> wrote:
>
>
>
> On 10/4/2024 11:30 PM, Alex Deucher wrote:
> > On Fri, Oct 4, 2024 at 5:15 AM Sundararaju, Sathishkumar
> > <sasundar@xxxxxxx> wrote:
> >>
> >> All occurrences of this error fix should have been together in a single patch both in _get and _set callbacks corresponding to f0b19b84d391, please avoid separate patch for each occurrence.
> >>
> >> Sorry Alex, I missed to note this yesterday.
> > I've dropped the patch.  Please pick it up once it's fixed up appropriately.
> Thanks Alex.
>
> Hi Advait,
> Please collate the changes together with Lijo's suggestion as well,
> "1ULL <<" instead of typecast, there are 3 occurrences of the error in
> f0b19b84d391.
>
> Regards,
> Sathish
> >
> > Thanks,
> >
> > Alex
> >
> >>
> >> Regards,
> >> Sathish
> >>
> >>
> >> On 10/4/2024 1:46 PM, Advait Dhamorikar wrote:
> >>
> >> Fix shift-count-overflow when creating mask.
> >> The expression's value may not be what the
> >> programmer intended, because the expression is
> >> evaluated using a narrower integer type.
> >>
> >> Fixes: f0b19b84d391 ("drm/amdgpu: add amdgpu_jpeg_sched_mask debugfs")
> >> Signed-off-by: Advait Dhamorikar <advaitdhamorikar@xxxxxxxxx>
> >> ---
> >>   drivers/gpu/drm/amd/amdgpu/amdgpu_jpeg.c | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_jpeg.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_jpeg.c
> >> index 95e2796919fc..7df402c45f40 100644
> >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_jpeg.c
> >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_jpeg.c
> >> @@ -388,7 +388,7 @@ static int amdgpu_debugfs_jpeg_sched_mask_get(void *data, u64 *val)
> >>    for (j = 0; j < adev->jpeg.num_jpeg_rings; ++j) {
> >>    ring = &adev->jpeg.inst[i].ring_dec[j];
> >>    if (ring->sched.ready)
> >> - mask |= 1 << ((i * adev->jpeg.num_jpeg_rings) + j);
> >> + mask |= (u64)1 << ((i * adev->jpeg.num_jpeg_rings) + j);
> >>    }
> >>    }
> >>    *val = mask;
>