RE: [PATCH v3] mac80211: LLVMLinux: Remove VLAIS usage from mac80211

Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This is the original VLAIS struct.

struct {
	struct aead_request     req;
	u8                      priv[crypto_aead_reqsize(tfm)];
} aead_req;

This patch instead allocates the appropriate amount of memory using an char
array.

The new code can be compiled with both gcc and clang.

Signed-off-by: Jan-Simon Mller <redacted>
Signed-off-by: Behan Webster <redacted>
Signed-off-by: Vincius Tinti <redacted>
Signed-off-by: Mark Charlebois <redacted>
---
 net/mac80211/aes_ccm.c | 40 ++++++++++++++++++++++------------------
 1 file changed, 22 insertions(+), 18 deletions(-)

diff --git a/net/mac80211/aes_ccm.c b/net/mac80211/aes_ccm.c
index 7c7df47..20521f9 100644
--- a/net/mac80211/aes_ccm.c
+++ b/net/mac80211/aes_ccm.c

@@ -23,12 +23,14 @@ void ieee80211_aes_ccm_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad,
 			       u8 *data, size_t data_len, u8 *mic)
 {
 	struct scatterlist assoc, pt, ct[2];
-	struct {
-		struct aead_request	req;
-		u8			priv[crypto_aead_reqsize(tfm)];
-	} aead_req;

-	memset(&aead_req, 0, sizeof(aead_req));
+	char aead_req_data[sizeof(struct aead_request) +
+		crypto_aead_reqsize(tfm)]
+		__aligned(__alignof__(struct aead_request));
+
+	struct aead_request *aead_req = (void *) aead_req_data;
+
+	memset(aead_req, 0, sizeof(aead_req_data));