From: Jan-Simon Möller <dl9pf@gmx.de>
Date: Mon, 2 Jul 2012 10:54:28 +0000 (+0200)
Subject: crypto: LLVMLinux: Remove VLAIS usage from libcrc32c.c
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=ea0e0de69fc413aa80dbf1ec1fb9702ea1b6faca;p=openwrt%2Fstaging%2Fblogic.git

crypto: LLVMLinux: Remove VLAIS usage from libcrc32c.c

Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using a char array using the SHASH_DESC_ON_STACK macro.

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

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: pageexec@freemail.hu
Cc: "David S. Miller" <davem@davemloft.net>
---

diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c
index b3131f5cf8a2..6a08ce7d6adc 100644
--- a/lib/libcrc32c.c
+++ b/lib/libcrc32c.c
@@ -41,20 +41,18 @@ static struct crypto_shash *tfm;
 
 u32 crc32c(u32 crc, const void *address, unsigned int length)
 {
-	struct {
-		struct shash_desc shash;
-		char ctx[crypto_shash_descsize(tfm)];
-	} desc;
+	SHASH_DESC_ON_STACK(shash, tfm);
+	u32 *ctx = (u32 *)shash_desc_ctx(shash);
 	int err;
 
-	desc.shash.tfm = tfm;
-	desc.shash.flags = 0;
-	*(u32 *)desc.ctx = crc;
+	shash->tfm = tfm;
+	shash->flags = 0;
+	*ctx = crc;
 
-	err = crypto_shash_update(&desc.shash, address, length);
+	err = crypto_shash_update(shash, address, length);
 	BUG_ON(err);
 
-	return *(u32 *)desc.ctx;
+	return *ctx;
 }
 
 EXPORT_SYMBOL(crc32c);