From 8694548ae1f245ad164d90d7aeafc7ab3bee71a4 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" 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 Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/perf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/firmware') 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 v1.2.3