crypto, dm: LLVMLinux: Remove VLAIS usage from dm-crypt

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: gmazyland@gmail.com
Cc: "David S. Miller" <davem@davemloft.net>

1 files changed, 14 insertions, 20 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index cd15e0801228..fc93b9330af4 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -526,29 +526,26 @@ static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
                             u8 *data)
 {
         struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
-        struct {
-                struct shash_desc desc;
-                char ctx[crypto_shash_descsize(lmk->hash_tfm)];
-        } sdesc;
+        SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
         struct md5_state md5state;
         __le32 buf[4];
         int i, r;
 
-        sdesc.desc.tfm = lmk->hash_tfm;
-        sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+        desc->tfm = lmk->hash_tfm;
+        desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
 
-        r = crypto_shash_init(&sdesc.desc);
+        r = crypto_shash_init(desc);
         if (r)
                 return r;
 
         if (lmk->seed) {
-                r = crypto_shash_update(&sdesc.desc, lmk->seed, LMK_SEED_SIZE);
+                r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
                 if (r)
                         return r;
         }
 
         /* Sector is always 512B, block size 16, add data of blocks 1-31 */
-        r = crypto_shash_update(&sdesc.desc, data + 16, 16 * 31);
+        r = crypto_shash_update(desc, data + 16, 16 * 31);
         if (r)
                 return r;
 
@@ -557,12 +554,12 @@ static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
         buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
         buf[2] = cpu_to_le32(4024);
         buf[3] = 0;
-        r = crypto_shash_update(&sdesc.desc, (u8 *)buf, sizeof(buf));
+        r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
         if (r)
                 return r;
 
         /* No MD5 padding here */
-        r = crypto_shash_export(&sdesc.desc, &md5state);
+        r = crypto_shash_export(desc, &md5state);
         if (r)
                 return r;
 
@@ -679,10 +676,7 @@ static int crypt_iv_tcw_whitening(struct crypt_config *cc,
         struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
         u64 sector = cpu_to_le64((u64)dmreq->iv_sector);
         u8 buf[TCW_WHITENING_SIZE];
-        struct {
-                struct shash_desc desc;
-                char ctx[crypto_shash_descsize(tcw->crc32_tfm)];
-        } sdesc;
+        SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
         int i, r;
 
         /* xor whitening with sector number */
@@ -691,16 +685,16 @@ static int crypt_iv_tcw_whitening(struct crypt_config *cc,
         crypto_xor(&buf[8], (u8 *)&sector, 8);
 
         /* calculate crc32 for every 32bit part and xor it */
-        sdesc.desc.tfm = tcw->crc32_tfm;
-        sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+        desc->tfm = tcw->crc32_tfm;
+        desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
         for (i = 0; i < 4; i++) {
-                r = crypto_shash_init(&sdesc.desc);
+                r = crypto_shash_init(desc);
                 if (r)
                         goto out;
-                r = crypto_shash_update(&sdesc.desc, &buf[i * 4], 4);
+                r = crypto_shash_update(desc, &buf[i * 4], 4);
                 if (r)
                         goto out;
-                r = crypto_shash_final(&sdesc.desc, &buf[i * 4]);
+                r = crypto_shash_final(desc, &buf[i * 4]);
                 if (r)
                         goto out;
         }