From 2b4496ce8485ec5efb93028f5a20bf1e48463b8c Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 11 Feb 2020 17:42:37 -0600 Subject: [PATCH] hwmon: (ibmaem) 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") Signed-off-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/20200211234237.GA26971@embeddedor Signed-off-by: Guenter Roeck --- drivers/hwmon/ibmaem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/ibmaem.c b/drivers/hwmon/ibmaem.c index d05ab713566df0..a4ec85207782d8 100644 --- a/drivers/hwmon/ibmaem.c +++ b/drivers/hwmon/ibmaem.c @@ -219,7 +219,7 @@ struct aem_read_sensor_req { struct aem_read_sensor_resp { struct aem_iana_id id; - u8 bytes[0]; + u8 bytes[]; } __packed; /* Data structures to talk to the IPMI layer */