[PATCH] drm/mediatek/dp: fix spurious kfree()

Michael Walle
2024-05-17T09:30:35Z

drm_edid_to_sad() might return an error or just zero. If that is the
case, we must not free the SADs because there was no allocation in
the first place.

Fixes: dab12fa8d2bd ("drm/mediatek/dp: fix memory leak on ->get_edid callback audio detection")
Signed-off-by: Michael Walle <mwalle@kernel.org>
---
drivers/gpu/drm/mediatek/mtk_dp.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index 536366956447..ada12927bbac 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -2073,9 +2073,15 @@ static const struct drm_edid *mtk_dp_edid_read(struct drm_bridge *bridge,
*/
const struct edid *edid = drm_edid_raw(drm_edid);
struct cea_sad *sads;
+ int ret;

- audio_caps->sad_count = drm_edid_to_sad(edid, &sads);
- kfree(sads);
+ ret = drm_edid_to_sad(edid, &sads);
+ /* Ignore any errors */
+ if (ret < 0)
+ ret = 0;
+ if (ret)
+ kfree(sads);
+ audio_caps->sad_count = ret;

/*
* FIXME: This should use connector->display_info.has_audio from
--
2.39.2