[PATCH 04/23] ASoC: cros_ec_codec: remove null pointer dereference warning

From: Pierre-Louis Bossart
Date: Fri Mar 12 2021 - 13:23:51 EST


Cppcheck complains of a possible issue:

sound/soc/codecs/cros_ec_codec.c:98:10: warning: Possible null pointer
dereference: in [nullPointer]
memcpy(in, msg->data, insize);
^
sound/soc/codecs/cros_ec_codec.c:162:34: note: Calling function
'send_ec_host_command', 5th argument 'NULL' value is 0
(uint8_t *)&p, sizeof(p), NULL, 0);
^
sound/soc/codecs/cros_ec_codec.c:98:10: note: Null pointer dereference
memcpy(in, msg->data, insize);
^

In practice the access to the pointer is protected by another
argument, but this is likely to fool other static analysis tools. Add
a test to avoid doing the memcpy if the pointer is NULL or the size is
zero.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
---
sound/soc/codecs/cros_ec_codec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/cros_ec_codec.c b/sound/soc/codecs/cros_ec_codec.c
index c4772f82485a..a201d652aca2 100644
--- a/sound/soc/codecs/cros_ec_codec.c
+++ b/sound/soc/codecs/cros_ec_codec.c
@@ -94,7 +94,7 @@ static int send_ec_host_command(struct cros_ec_device *ec_dev, uint32_t cmd,
if (ret < 0)
goto error;

- if (insize)
+ if (in && insize)
memcpy(in, msg->data, insize);

ret = 0;
--
2.25.1