From: Eric Biggers Subject: [PATCH] crypto: cmac - fix alignment of 'consts' Date: Mon, 10 Oct 2016 10:15:15 -0700 Message-ID: <1476119715-71397-2-git-send-email-ebiggers@google.com> Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Biggers To: herbert@gondor.apana.org.au, davem@davemloft.net Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org 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 --- crypto/cmac.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/crypto/cmac.c b/crypto/cmac.c index b6c4059..04080dc 100644 --- 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; -- 2.8.0.rc3.226.g39d4020