Patch "ASoC: mediatek: common: handle NULL case in suspend/resume function" has been added to the 5.14-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ASoC: mediatek: common: handle NULL case in suspend/resume function

to the 5.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     asoc-mediatek-common-handle-null-case-in-suspend-res.patch
and it can be found in the queue-5.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 6d426d2bcd2ba1d8651bec5b792bb6f16e30017d
Author: Trevor Wu <trevor.wu@xxxxxxxxxxxx>
Date:   Fri Sep 10 17:26:13 2021 +0800

    ASoC: mediatek: common: handle NULL case in suspend/resume function
    
    [ 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@xxxxxxxxxxxx>
    Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20210910092613.30188-1-trevor.wu@xxxxxxxxxxxx
    Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

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;