[PATCH 5.14 009/172] ASoC: mediatek: common: handle NULL case in suspend/resume function

Greg Kroah-Hartman
2021-10-04T13:29:20Z

From: Trevor Wu <trevor.wu@mediatek.com>

[ Upstream commit 1dd038522615b70f5f8945c5631e9e2fa5bd58b1 ]

When memory allocation for afe->reg_back_up fails, reg_back_up can't
be used.
Keep the suspend/resume flow but skip register backup when
afe->reg_back_up is NULL, in case illegal memory access happens.

Fixes: 283b612429a2 ("ASoC: mediatek: implement mediatek common structure")
Signed-off-by: Trevor Wu <trevor.wu@mediatek.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210910092613.30188-1-trevor.wu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
sound/soc/mediatek/common/mtk-afe-fe-dai.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/sound/soc/mediatek/common/mtk-afe-fe-dai.c b/sound/soc/mediatek/common/mtk-afe-fe-dai.c
index 3cb2adf420bb..ab7bbd53bb01 100644
--- a/sound/soc/mediatek/common/mtk-afe-fe-dai.c
+++ b/sound/soc/mediatek/common/mtk-afe-fe-dai.c
@@ -334,9 +334,11 @@ int mtk_afe_suspend(struct snd_soc_component *component)
devm_kcalloc(dev, afe->reg_back_up_list_num,
sizeof(unsigned int), GFP_KERNEL);

- for (i = 0; i < afe->reg_back_up_list_num; i++)
- regmap_read(regmap, afe->reg_back_up_list[i],
- &afe->reg_back_up[i]);
+ if (afe->reg_back_up) {
+ for (i = 0; i < afe->reg_back_up_list_num; i++)
+ regmap_read(regmap, afe->reg_back_up_list[i],
+ &afe->reg_back_up[i]);
+ }

afe->suspended = true;
afe->runtime_suspend(dev);
@@ -356,12 +358,13 @@ int mtk_afe_resume(struct snd_soc_component *component)

afe->runtime_resume(dev);

- if (!afe->reg_back_up)
+ if (!afe->reg_back_up) {
dev_dbg(dev, "%s no reg_backup\n", __func__);
-
- for (i = 0; i < afe->reg_back_up_list_num; i++)
- mtk_regmap_write(regmap, afe->reg_back_up_list[i],
- afe->reg_back_up[i]);
+ } else {
+ for (i = 0; i < afe->reg_back_up_list_num; i++)
+ mtk_regmap_write(regmap, afe->reg_back_up_list[i],
+ afe->reg_back_up[i]);
+ }

afe->suspended = false;
return 0;
--
2.33.0