2022-03-28 07:40:26

by Xiaomeng Tong

[permalink] [raw]
Subject: [PATCH] soc: meson: fix a missing check on list iterator

The bug is here:
*dai_name = dai->driver->name;

For for_each_component_dais(), just like list_for_each_entry,
the list iterator 'runtime' will point to a bogus position
containing HEAD if the list is empty or no element is found.
This case must be checked before any use of the iterator,
otherwise it will lead to a invalid memory access.

To fix the bug, just move the assignment into loop and return
0 when element is found, otherwise return -EINVAL;

Cc: [email protected]
Fixes: 6ae9ca9ce986b ("ASoC: meson: aiu: add i2s and spdif support")
Signed-off-by: Xiaomeng Tong <[email protected]>
---
sound/soc/meson/aiu.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/sound/soc/meson/aiu.c b/sound/soc/meson/aiu.c
index d299a70db7e5..b52915c6f53b 100644
--- a/sound/soc/meson/aiu.c
+++ b/sound/soc/meson/aiu.c
@@ -61,14 +61,14 @@ int aiu_of_xlate_dai_name(struct snd_soc_component *component,
return -EINVAL;

for_each_component_dais(component, dai) {
- if (id == 0)
- break;
+ if (id == 0) {
+ *dai_name = dai->driver->name;
+ return 0;
+ }
id--;
}

- *dai_name = dai->driver->name;
-
- return 0;
+ return -EINVAL;
}

static int aiu_cpu_of_xlate_dai_name(struct snd_soc_component *component,
--
2.17.1