Re: [PATCH v4 3/3] crypto: Add Allwinner Security System crypto accelerator
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: 2014-07-24 06:01:56
Also in:
linux-arm-kernel, linux-crypto, lkml
On Sat, Jul 12, 2014 at 02:59:13PM +0200, LABBE Corentin wrote:
+/* sunxi_hash_init: initialize request context
+ * Activate the SS, and configure it for MD5 or SHA1
+ */
+int sunxi_hash_init(struct ahash_request *areq)
+{
+ const char *hash_type;
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
+ struct sunxi_req_ctx *op = crypto_ahash_ctx(tfm);
+
+ mutex_lock(&ss->lock);
+
+ hash_type = crypto_tfm_alg_name(areq->base.tfm);
+
+ op->byte_count = 0;
+ op->nbwait = 0;
+ op->waitbuf = 0;
+
+ /* Enable and configure SS for MD5 or SHA1 */
+ if (strcmp(hash_type, "sha1") == 0)
+ op->mode = SS_OP_SHA1;
+ else
+ op->mode = SS_OP_MD5;
+
+ writel(op->mode | SS_ENABLED, ss->base + SS_CTL);
+ return 0;The hash driver is completely broken. You are modifying tfm ctx data which is shared by all users of a single tfm. So if two users conduct hashes in parallel they will step all over each other. Worse, the unpaired mutex_lock will quickly lead to dead locks. You cannot assume that final will be called. Cheers, -- Email: Herbert Xu [off-list ref] Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt