[PATCH 2/2] firmware: arm_scmi: Fix pointers arithmetic in Base protocol

From: Cristian Marussi
Date: Mon May 30 2022 - 07:53:26 EST


Fix a possible undefined behaviour involving pointer arithmetic in Base
protocol scmi_base_implementation_list_get().

cppcheck complains with:

drivers/firmware/arm_scmi/base.c:190:19: warning: 't->rx.buf' is of type 'void *'. When using void pointers in calculations, the behaviour is undefined. [arithOperationsOnVoidPointer]
list = t->rx.buf + sizeof(*num_ret);

Fixes: b6f20ff8bd94 ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
drivers/firmware/arm_scmi/base.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c
index 20fba7370f4e..6d6214d9e68c 100644
--- a/drivers/firmware/arm_scmi/base.c
+++ b/drivers/firmware/arm_scmi/base.c
@@ -187,7 +187,7 @@ scmi_base_implementation_list_get(const struct scmi_protocol_handle *ph,

num_skip = t->tx.buf;
num_ret = t->rx.buf;
- list = t->rx.buf + sizeof(*num_ret);
+ list = ((u8 *)t->rx.buf) + sizeof(*num_ret);

do {
size_t real_list_sz;
--
2.32.0