Messages in this thread | | | Subject | Re: [PATCH] drm/tegra: remove no need NULL check before kfree | From | Mikko Perttunen <> | Date | Tue, 16 Nov 2021 12:01:05 +0200 |
| |
On 11/16/21 3:55 AM, Bernard Zhao wrote: > This change is to cleanup the code a bit. > > Signed-off-by: Bernard Zhao <bernard@vivo.com> > --- > drivers/gpu/drm/tegra/submit.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/tegra/submit.c b/drivers/gpu/drm/tegra/submit.c > index 776f825df52f..c2fc9677742e 100644 > --- a/drivers/gpu/drm/tegra/submit.c > +++ b/drivers/gpu/drm/tegra/submit.c > @@ -608,12 +608,10 @@ int tegra_drm_ioctl_channel_submit(struct drm_device *drm, void *data, > if (job_data && job_data->used_mappings) { > for (i = 0; i < job_data->num_used_mappings; i++) > tegra_drm_mapping_put(job_data->used_mappings[i].mapping); > - > - kfree(job_data->used_mappings); > } > > - if (job_data) > - kfree(job_data); > + kfree(job_data->used_mappings);
Now if job_data == NULL, we dereference a NULL pointer here.
In general I'm not a fan of relying on kfree() etc. being a no-op on NULL pointers, since doing so gets rid of visual hints on code paths indicating the "liveness" of pointer variables.
However I'll let Thierry/other maintainers decide according to their preferences.
Thanks, Mikko
> + kfree(job_data); > put_bo: > gather_bo_put(&bo->base); > unlock: >
| |