Re: [PATCH v3] drm/amdgpu: off by one in amdgpu_device_attr_create_groups() error handling

[Christian KÃnig]

Am 20.05.20 um 17:31 schrieb Ruhl, Michael J:
> > -----Original Message-----
> > From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > Sent: Wednesday, May 20, 2020 11:26 AM
> > To: Alex Deucher <alexander.deucher@xxxxxxx>; Kevin Wang
> > <kevin1.wang@xxxxxxx>; Ruhl, Michael J <michael.j.ruhl@xxxxxxxxx>
> > Cc: Christian KÃnig <christian.koenig@xxxxxxx>; David Airlie
> > <airlied@xxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; Evan Quan
> > <evan.quan@xxxxxxx>; Rui Huang <ray.huang@xxxxxxx>; Kenneth Feng
> > <kenneth.feng@xxxxxxx>; Yintian Tao <yttao@xxxxxxx>; Hawking Zhang
> > <Hawking.Zhang@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx; dri-
> > devel@xxxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; kernel-
> > janitors@xxxxxxxxxxxxxxx
> > Subject: [PATCH v3] drm/amdgpu: off by one in
> > amdgpu_device_attr_create_groups() error handling
> >
> > This loop in the error handling code should start a "i - 1" and end at
> > "i == 0".  Currently it starts a "i" and ends at "i == 1".  The result
> > is that it removes one attribute that wasn't created yet, and leaks the
> > zeroeth attribute.
> >
> > Fixes: 4e01847c38f7 ("drm/amdgpu: optimize amdgpu device attribute code")
> > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > ---
> > v2: style change
> > v3: Fix embarrassing typo in the subject
> ð
>
> Acked-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>

Reviewed-by: Christian KÃnig <christian.koenig@xxxxxxx>

> m
> > drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c           | 3 +--
> > 1 files changed, 1 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> > b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> > index b75362bf0742..e809534fabd4 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
> > @@ -1942,9 +1942,8 @@ static int amdgpu_device_attr_create_groups(struct
> > amdgpu_device *adev,
> > 	return 0;
> >
> > failed:
> > -	for (; i > 0; i--) {
> > +	while (i--)
> > 		amdgpu_device_attr_remove(adev, &attrs[i]);
> > -	}
> >
> > 	return ret;
> > }