crypto: s390/ghash - Fix incorrect ghash icv buffer handling.

Multitheaded tests showed that the icv buffer in the current ghash
implementation is not handled correctly. A move of this working ghash
buffer value to the descriptor context fixed this. Code is tested and
verified with an multithreaded application via af_alg interface.

Cc: stable@vger.kernel.org
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Gerald Schaefer <geraldsc@linux.vnet.ibm.com>
Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 13 insertions, 12 deletions

diff --git a/arch/s390/crypto/ghash_s390.c b/arch/s390/crypto/ghash_s390.c
index 7940dc90e80b..b258110da952 100644
--- a/arch/s390/crypto/ghash_s390.c
+++ b/arch/s390/crypto/ghash_s390.c
@@ -16,11 +16,12 @@
 #define GHASH_DIGEST_SIZE       16
 
 struct ghash_ctx {
-        u8 icv[16];
-        u8 key[16];
+        u8 key[GHASH_BLOCK_SIZE];
 };
 
 struct ghash_desc_ctx {
+        u8 icv[GHASH_BLOCK_SIZE];
+        u8 key[GHASH_BLOCK_SIZE];
         u8 buffer[GHASH_BLOCK_SIZE];
         u32 bytes;
 };
@@ -28,8 +29,10 @@ struct ghash_desc_ctx {
 static int ghash_init(struct shash_desc *desc)
 {
         struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
+        struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
 
         memset(dctx, 0, sizeof(*dctx));
+        memcpy(dctx->key, ctx->key, GHASH_BLOCK_SIZE);
 
         return 0;
 }
@@ -45,7 +48,6 @@ static int ghash_setkey(struct crypto_shash *tfm,
         }
 
         memcpy(ctx->key, key, GHASH_BLOCK_SIZE);
-        memset(ctx->icv, 0, GHASH_BLOCK_SIZE);
 
         return 0;
 }
@@ -54,7 +56,6 @@ static int ghash_update(struct shash_desc *desc,
                          const u8 *src, unsigned int srclen)
 {
         struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
-        struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
         unsigned int n;
         u8 *buf = dctx->buffer;
         int ret;
@@ -70,7 +71,7 @@ static int ghash_update(struct shash_desc *desc,
                 src += n;
 
                 if (!dctx->bytes) {
-                        ret = crypt_s390_kimd(KIMD_GHASH, ctx, buf,
+                        ret = crypt_s390_kimd(KIMD_GHASH, dctx, buf,
                                               GHASH_BLOCK_SIZE);
                         if (ret != GHASH_BLOCK_SIZE)
                                 return -EIO;
@@ -79,7 +80,7 @@ static int ghash_update(struct shash_desc *desc,
 
         n = srclen & ~(GHASH_BLOCK_SIZE - 1);
         if (n) {
-                ret = crypt_s390_kimd(KIMD_GHASH, ctx, src, n);
+                ret = crypt_s390_kimd(KIMD_GHASH, dctx, src, n);
                 if (ret != n)
                         return -EIO;
                 src += n;
@@ -94,7 +95,7 @@ static int ghash_update(struct shash_desc *desc,
         return 0;
 }
 
-static int ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
+static int ghash_flush(struct ghash_desc_ctx *dctx)
 {
         u8 *buf = dctx->buffer;
         int ret;
@@ -104,24 +105,24 @@ static int ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
 
                 memset(pos, 0, dctx->bytes);
 
-                ret = crypt_s390_kimd(KIMD_GHASH, ctx, buf, GHASH_BLOCK_SIZE);
+                ret = crypt_s390_kimd(KIMD_GHASH, dctx, buf, GHASH_BLOCK_SIZE);
                 if (ret != GHASH_BLOCK_SIZE)
                         return -EIO;
+
+                dctx->bytes = 0;
         }
 
-        dctx->bytes = 0;
         return 0;
 }
 
 static int ghash_final(struct shash_desc *desc, u8 *dst)
 {
         struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
-        struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
         int ret;
 
-        ret = ghash_flush(ctx, dctx);
+        ret = ghash_flush(dctx);
         if (!ret)
-                memcpy(dst, ctx->icv, GHASH_BLOCK_SIZE);
+                memcpy(dst, dctx->icv, GHASH_BLOCK_SIZE);
         return ret;
 }