linux-kernel - [char-misc-next 4/5] mei: bus: elminate variable length arrays

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Date:   Mon, 20 Mar 2017 15:04:05 +0200
From:   Tomas Winkler <tomas.winkler@...el.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     Alexander Usyskin <alexander.usyskin@...el.com>,
        linux-kernel@...r.kernel.org,
        Tomas Winkler <tomas.winkler@...el.com>
Subject: [char-misc-next 4/5] mei: bus: elminate variable length arrays

Though VLA are supported by CC99 there are many cavities
and should be avoided.

'const size_t len = sizeof()' that we used may not be set
at the compile time hence generating VLA code.

This fixes also sparse warning
warning: Variable length array is used type.

Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---
 drivers/misc/mei/bus-fixup.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/mei/bus-fixup.c b/drivers/misc/mei/bus-fixup.c
index 29f2daed37e0..0208c4b027c5 100644
--- a/drivers/misc/mei/bus-fixup.c
+++ b/drivers/misc/mei/bus-fixup.c
@@ -110,12 +110,13 @@ struct mkhi_msg {
 	u8 data[0];
 } __packed;
 
+#define MKHI_OSVER_BUF_LEN (sizeof(struct mkhi_msg_hdr) + \
+			    sizeof(struct mkhi_fwcaps) + \
+			    sizeof(struct mei_os_ver))
 static int mei_osver(struct mei_cl_device *cldev)
 {
-	const size_t size = sizeof(struct mkhi_msg_hdr) +
-			    sizeof(struct mkhi_fwcaps) +
-			    sizeof(struct mei_os_ver);
-	char buf[size];
+	const size_t size = MKHI_OSVER_BUF_LEN;
+	char buf[MKHI_OSVER_BUF_LEN];
 	struct mkhi_msg *req;
 	struct mkhi_fwcaps *fwcaps;
 	struct mei_os_ver *os_ver;
-- 
2.9.3