From 8694548ae1f245ad164d90d7aeafc7ab3bee71a4 Mon Sep 17 00:00:00 2001
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Date: Tue, 11 Feb 2020 17:12:52 -0600
Subject: firmware: arm_scmi/perf: Replace zero-length array with
flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Replace the zero-length member "opp" in scmi_msg_resp_perf_describe_levels
structure with flexible-array.
Link: https://lore.kernel.org/r/20200211231252.GA14830@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
drivers/firmware/arm_scmi/perf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
(limited to 'drivers/firmware/arm_scmi/perf.c')
diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index ec81e6f7e7a4..34f3a917dd8d 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -89,7 +89,7 @@ struct scmi_msg_resp_perf_describe_levels {
__le32 power;
__le16 transition_latency_us;
__le16 reserved;
- } opp[0];
+ } opp[];
};
struct scmi_perf_get_fc_info {
--
cgit