crypto: nx - Fixing SHA update bug

Bug happens when a data size less than SHA block size is passed.
Since first attempt will be saved in buffer, second round attempt
get into two step to calculate op.inlen and op.outlen. The issue
resides in this step. A wrong value of op.inlen and outlen was being
calculated.

This patch fix this eliminate the nx_sha_build_sg_list, that is
useless in SHA's algorithm context. Instead we call nx_build_sg_list
directly and pass a previous calculated max_sg_len to it.

Signed-off-by: Leonidas S. Barbosa <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/nx/nx-sha256.c

···
 {
 	struct sha256_state *sctx = shash_desc_ctx(desc);
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
+	struct nx_sg *out_sg;
 	int len;
-	int rc;
+	u32 max_sg_len;
 
 	nx_ctx_init(nx_ctx, HCOP_FC_SHA);
 
···
 
 	NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA256);
 
-	len = SHA256_DIGEST_SIZE;
-	rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->out_sg,
-				  &nx_ctx->op.outlen,
-				  &len,
-				  (u8 *) sctx->state,
-				  NX_DS_SHA256);
+	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
+			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
+	max_sg_len = min_t(u64, max_sg_len,
+			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 
-	if (rc)
-		goto out;
+	len = SHA256_DIGEST_SIZE;
+	out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
+				  &len, max_sg_len);
+	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
+
+	if (len != SHA256_DIGEST_SIZE)
+		return -EINVAL;
 
 	sctx->state[0] = __cpu_to_be32(SHA256_H0);
 	sctx->state[1] = __cpu_to_be32(SHA256_H1);
···
 	sctx->state[7] = __cpu_to_be32(SHA256_H7);
 	sctx->count = 0;
 
-out:
 	return 0;
 }
 
···
 	struct sha256_state *sctx = shash_desc_ctx(desc);
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
+	struct nx_sg *in_sg;
 	u64 to_process = 0, leftover, total;
 	unsigned long irq_flags;
 	int rc = 0;
 	int data_len;
+	u32 max_sg_len;
 	u64 buf_len = (sctx->count % SHA256_BLOCK_SIZE);
 
 	spin_lock_irqsave(&nx_ctx->lock, irq_flags);
···
 	NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
 	NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
 
+	in_sg = nx_ctx->in_sg;
+	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
+			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
+	max_sg_len = min_t(u64, max_sg_len,
+			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
+
 	do {
 		/*
 		 * to_process: the SHA256_BLOCK_SIZE data chunk to process in
···
 
 		if (buf_len) {
 			data_len = buf_len;
-			rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->in_sg,
-						  &nx_ctx->op.inlen,
-						  &data_len,
-						  (u8 *) sctx->buf,
-						  NX_DS_SHA256);
+			in_sg = nx_build_sg_list(nx_ctx->in_sg,
+						 (u8 *) sctx->buf,
+						 &data_len,
+						 max_sg_len);
 
-			if (rc || data_len != buf_len)
+			if (data_len != buf_len) {
+				rc = -EINVAL;
 				goto out;
+			}
 		}
 
 		data_len = to_process - buf_len;
-		rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->in_sg,
-					  &nx_ctx->op.inlen,
-					  &data_len,
-					  (u8 *) data,
-					  NX_DS_SHA256);
+		in_sg = nx_build_sg_list(in_sg, (u8 *) data,
+					 &data_len, max_sg_len);
 
-		if (rc)
-			goto out;
+		nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
 
 		to_process = (data_len + buf_len);
 		leftover = total - to_process;
···
 	struct sha256_state *sctx = shash_desc_ctx(desc);
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
+	struct nx_sg *in_sg, *out_sg;
 	unsigned long irq_flags;
-	int rc;
+	u32 max_sg_len;
+	int rc = 0;
 	int len;
 
 	spin_lock_irqsave(&nx_ctx->lock, irq_flags);
+
+	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
+			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
+	max_sg_len = min_t(u64, max_sg_len,
+			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 
 	/* final is represented by continuing the operation and indicating that
 	 * this is not an intermediate operation */
···
 	csbcpb->cpb.sha256.message_bit_length = (u64) (sctx->count * 8);
 
 	len = sctx->count & (SHA256_BLOCK_SIZE - 1);
-	rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->in_sg,
-				  &nx_ctx->op.inlen,
-				  &len,
-				  (u8 *) sctx->buf,
-				  NX_DS_SHA256);
+	in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) sctx->buf,
+				 &len, max_sg_len);
 
-	if (rc || len != (sctx->count & (SHA256_BLOCK_SIZE - 1)))
+	if (len != (sctx->count & (SHA256_BLOCK_SIZE - 1))) {
+		rc = -EINVAL;
 		goto out;
+	}
 
 	len = SHA256_DIGEST_SIZE;
-	rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->out_sg,
-				  &nx_ctx->op.outlen,
-				  &len,
-				  out,
-				  NX_DS_SHA256);
+	out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len, max_sg_len);
 
-	if (rc || len != SHA256_DIGEST_SIZE)
+	if (len != SHA256_DIGEST_SIZE) {
+		rc = -EINVAL;
 		goto out;
+	}
 
+	nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
+	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 	if (!nx_ctx->op.outlen) {
 		rc = -EINVAL;
 		goto out;

drivers/crypto/nx/nx-sha512.c

···
 {
 	struct sha512_state *sctx = shash_desc_ctx(desc);
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
+	struct nx_sg *out_sg;
 	int len;
-	int rc;
+	u32 max_sg_len;
 
 	nx_ctx_init(nx_ctx, HCOP_FC_SHA);
 
···
 
 	NX_CPB_SET_DIGEST_SIZE(nx_ctx->csbcpb, NX_DS_SHA512);
 
-	len = SHA512_DIGEST_SIZE;
-	rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->out_sg,
-				  &nx_ctx->op.outlen,
-				  &len,
-				  (u8 *)sctx->state,
-				  NX_DS_SHA512);
+	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
+			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
+	max_sg_len = min_t(u64, max_sg_len,
+			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 
-	if (rc || len != SHA512_DIGEST_SIZE)
-		goto out;
+	len = SHA512_DIGEST_SIZE;
+	out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
+				  &len, max_sg_len);
+	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
+
+	if (len != SHA512_DIGEST_SIZE)
+		return -EINVAL;
 
 	sctx->state[0] = __cpu_to_be64(SHA512_H0);
 	sctx->state[1] = __cpu_to_be64(SHA512_H1);
···
 	sctx->state[7] = __cpu_to_be64(SHA512_H7);
 	sctx->count[0] = 0;
 
-out:
 	return 0;
 }
 
···
 	struct sha512_state *sctx = shash_desc_ctx(desc);
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
+	struct nx_sg *in_sg;
 	u64 to_process, leftover = 0, total;
 	unsigned long irq_flags;
 	int rc = 0;
 	int data_len;
+	u32 max_sg_len;
 	u64 buf_len = (sctx->count[0] % SHA512_BLOCK_SIZE);
 
 	spin_lock_irqsave(&nx_ctx->lock, irq_flags);
···
 	NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
 	NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
 
+	in_sg = nx_ctx->in_sg;
+	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
+			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
+	max_sg_len = min_t(u64, max_sg_len,
+			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
+
 	do {
 		/*
 		 * to_process: the SHA512_BLOCK_SIZE data chunk to process in
···
 
 		if (buf_len) {
 			data_len = buf_len;
-			rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->in_sg,
-						  &nx_ctx->op.inlen,
-						  &data_len,
-						  (u8 *) sctx->buf,
-						  NX_DS_SHA512);
+			in_sg = nx_build_sg_list(nx_ctx->in_sg,
+						 (u8 *) sctx->buf,
+						 &data_len, max_sg_len);
 
-			if (rc || data_len != buf_len)
+			if (data_len != buf_len) {
+				rc = -EINVAL;
 				goto out;
+			}
 		}
 
 		data_len = to_process - buf_len;
-		rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->in_sg,
-					  &nx_ctx->op.inlen,
-					  &data_len,
-					  (u8 *) data,
-					  NX_DS_SHA512);
+		in_sg = nx_build_sg_list(in_sg, (u8 *) data,
+					 &data_len, max_sg_len);
 
-		if (rc || data_len != (to_process - buf_len))
+		nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
+
+		if (data_len != (to_process - buf_len)) {
+			rc = -EINVAL;
 			goto out;
+		}
 
 		to_process = (data_len + buf_len);
 		leftover = total - to_process;
···
 	struct sha512_state *sctx = shash_desc_ctx(desc);
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base);
 	struct nx_csbcpb *csbcpb = (struct nx_csbcpb *)nx_ctx->csbcpb;
+	struct nx_sg *in_sg, *out_sg;
+	u32 max_sg_len;
 	u64 count0;
 	unsigned long irq_flags;
-	int rc;
+	int rc = 0;
 	int len;
 
 	spin_lock_irqsave(&nx_ctx->lock, irq_flags);
+
+	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
+			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
+	max_sg_len = min_t(u64, max_sg_len,
+			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
 
 	/* final is represented by continuing the operation and indicating that
 	 * this is not an intermediate operation */
···
 	csbcpb->cpb.sha512.message_bit_length_lo = count0;
 
 	len = sctx->count[0] & (SHA512_BLOCK_SIZE - 1);
-	rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->in_sg,
-				  &nx_ctx->op.inlen,
-				  &len,
-				  (u8 *)sctx->buf,
-				  NX_DS_SHA512);
+	in_sg = nx_build_sg_list(nx_ctx->in_sg, sctx->buf, &len,
+				 max_sg_len);
 
-	if (rc || len != (sctx->count[0] & (SHA512_BLOCK_SIZE - 1)))
+	if (len != (sctx->count[0] & (SHA512_BLOCK_SIZE - 1))) {
+		rc = -EINVAL;
 		goto out;
+	}
 
 	len = SHA512_DIGEST_SIZE;
-	rc = nx_sha_build_sg_list(nx_ctx, nx_ctx->out_sg,
-				  &nx_ctx->op.outlen,
-				  &len,
-				  out,
-				  NX_DS_SHA512);
+	out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len,
+				 max_sg_len);
 
-	if (rc)
-		goto out;
+	nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
+	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 
 	if (!nx_ctx->op.outlen) {
 		rc = -EINVAL;

drivers/crypto/nx/nx.c

···
 }
 
 /**
- * nx_sha_build_sg_list - walk and build sg list to sha modes
- *			  using right bounds and limits.
- * @nx_ctx: NX crypto context for the lists we're building
- * @nx_sg: current sg list in or out list
- * @op_len: current op_len to be used in order to build a sg list
- * @nbytes:  number or bytes to be processed
- * @offset: buf offset
- * @mode: SHA256 or SHA512
- */
-int nx_sha_build_sg_list(struct nx_crypto_ctx *nx_ctx,
-			  struct nx_sg 	      *nx_in_outsg,
-			  s64		      *op_len,
-			  unsigned int        *nbytes,
-			  u8 		      *offset,
-			  u32		      mode)
-{
-	unsigned int delta = 0;
-	unsigned int total = *nbytes;
-	struct nx_sg *nx_insg = nx_in_outsg;
-	unsigned int max_sg_len;
-
-	max_sg_len = min_t(u64, nx_ctx->ap->sglen,
-			nx_driver.of.max_sg_len/sizeof(struct nx_sg));
-	max_sg_len = min_t(u64, max_sg_len,
-			nx_ctx->ap->databytelen/NX_PAGE_SIZE);
-
-	*nbytes = min_t(u64, *nbytes, nx_ctx->ap->databytelen);
-	nx_insg = nx_build_sg_list(nx_insg, offset, nbytes, max_sg_len);
-
-	switch (mode) {
-	case NX_DS_SHA256:
-		if (*nbytes < total)
-			delta = *nbytes - (*nbytes & ~(SHA256_BLOCK_SIZE - 1));
-		break;
-	case NX_DS_SHA512:
-		if (*nbytes < total)
-			delta = *nbytes - (*nbytes & ~(SHA512_BLOCK_SIZE - 1));
-		break;
-	default:
-		return -EINVAL;
-	}
-	*op_len = trim_sg_list(nx_in_outsg, nx_insg, delta);
-
-	return 0;
-}
-
-/**
  * nx_build_sg_lists - walk the input scatterlists and build arrays of NX
  *                     scatterlists based on them.
  *

drivers/crypto/nx/nx.h

···
 void nx_ctx_init(struct nx_crypto_ctx *nx_ctx, unsigned int function);
 int nx_hcall_sync(struct nx_crypto_ctx *ctx, struct vio_pfo_op *op,
 		  u32 may_sleep);
-int nx_sha_build_sg_list(struct nx_crypto_ctx *, struct nx_sg *,
-			 s64 *, unsigned int *, u8 *, u32);
 struct nx_sg *nx_build_sg_list(struct nx_sg *, u8 *, unsigned int *, u32);
 int nx_build_sg_lists(struct nx_crypto_ctx *, struct blkcipher_desc *,
 		      struct scatterlist *, struct scatterlist *, unsigned int *,