crypto: cmac - fix alignment of 'consts'

The per-transform 'consts' array is accessed as __be64 in
crypto_cmac_digest_setkey() but was only guaranteed to be aligned to
__alignof__(long).  Fix this by aligning it to __alignof__(__be64).

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/cmac.c b/crypto/cmac.c
index b6c4059..04080dc 100644 (file)
--- a/crypto/cmac.c
+++ b/crypto/cmac.c
@@ -57,7 +57,8 @@ static int crypto_cmac_digest_setkey(struct crypto_shash *parent,
        unsigned long alignmask = crypto_shash_alignmask(parent);
        struct cmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
        unsigned int bs = crypto_shash_blocksize(parent);
-       __be64 *consts = PTR_ALIGN((void *)ctx->ctx, alignmask + 1);
+       __be64 *consts = PTR_ALIGN((void *)ctx->ctx,
+                                  (alignmask | (__alignof__(__be64) - 1)) + 1);
        u64 _const[2];
        int i, err = 0;
        u8 msb_mask, gfmask;
@@ -173,7 +174,8 @@ static int crypto_cmac_digest_final(struct shash_desc *pdesc, u8 *out)
        struct cmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
        struct crypto_cipher *tfm = tctx->child;
        int bs = crypto_shash_blocksize(parent);
-       u8 *consts = PTR_ALIGN((void *)tctx->ctx, alignmask + 1);
+       u8 *consts = PTR_ALIGN((void *)tctx->ctx,
+                              (alignmask | (__alignof__(__be64) - 1)) + 1);
        u8 *odds = PTR_ALIGN((void *)ctx->ctx, alignmask + 1);
        u8 *prev = odds + bs;
        unsigned int offset = 0;
@@ -258,7 +260,8 @@ static int cmac_create(struct crypto_template *tmpl, struct rtattr **tb)
        if (err)
                goto out_free_inst;
 
-       alignmask = alg->cra_alignmask | (sizeof(long) - 1);
+       /* We access the data as u32s when xoring. */
+       alignmask = alg->cra_alignmask | (__alignof__(u32) - 1);
        inst->alg.base.cra_alignmask = alignmask;
        inst->alg.base.cra_priority = alg->cra_priority;
        inst->alg.base.cra_blocksize = alg->cra_blocksize;
@@ -270,7 +273,9 @@ static int cmac_create(struct crypto_template *tmpl, struct rtattr **tb)
                + alg->cra_blocksize * 2;
 
        inst->alg.base.cra_ctxsize =
-               ALIGN(sizeof(struct cmac_tfm_ctx), alignmask + 1)
+               ALIGN(sizeof(struct cmac_tfm_ctx), crypto_tfm_ctx_alignment())
+               + ((alignmask | (__alignof__(__be64) - 1)) &
+                  ~(crypto_tfm_ctx_alignment() - 1))
                + alg->cra_blocksize * 2;
 
        inst->alg.base.cra_init = cmac_init_tfm;