Re: [PATCH] drm/exynos: fix memory leak: free EDID block

[Jani Nikula <jani.nikula@linux.intel.com>]

On Tue, 20 Nov 2012, Sean Paul <seanpaul@chromium.org> wrote:
> On Tue, Nov 20, 2012 at 4:30 AM, Egbert Eich <eich@suse.de> wrote:
>> drm_get_edid() returns a pointer to an EDID block. The caller
>> is responsible to free this pointer itself.
>> Here the pointer gets assigned to the local variable raw_edid.
>> Therefore it should be freed before the variable goes out of
>> scope.
>>
>> Signed-off-by: Egbert Eich <eich@suse.de>
>> ---
>>  drivers/gpu/drm/exynos/exynos_hdmi.c |    1 +
>>  1 files changed, 1 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
>> index 2c115f8..bc87bca 100644
>> --- a/drivers/gpu/drm/exynos/exynos_hdmi.c
>> +++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
>> @@ -1293,6 +1293,7 @@ static int hdmi_get_edid(void *ctx, struct drm_connector *connector,
>>                 DRM_DEBUG_KMS("%s : width[%d] x height[%d]\n",
>>                         (hdata->dvi_mode ? "dvi monitor" : "hdmi monitor"),
>>                         raw_edid->width_cm, raw_edid->height_cm);
>> +               kfree(raw_edid);
>
> This will actually cause the memory to be freed twice.
>
> The reason this happens is drm_get_edid attaches this to
> connector->display_info.raw_edid, which is then freed in the
> exynos_drm_connector function that gets the edid.
>
> The whole thing is ugly, and needs to be revised. I've uploaded a
> patch to refactor this against the chromium tree, but haven't yet
> rebased against upstream. See
> https://gerrit.chromium.org/gerrit/#/c/38406/

The patch is good. connector->display_info.raw_edid is gone since

commit 451023dc32d4542c21b52ad1692e6e01cb75b099
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Wed Aug 15 09:32:39 2012 +0000

    drm: remove the raw_edid field from struct drm_display_info

BR,
Jani.


>
> For now, please drop this patch.
>
> Sean
>
>>         } else {
>>                 return -ENODEV;
>>         }
>> --
>> 1.7.7
>>
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> http://lists.freedesktop.org/mailman/listinfo/dri-devel
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel