crypto: ccp - Change data length declarations to u64

When performing a hash operation if the amount of data buffered and a
request at or near the maximum data length is received then the length
calcuation could wrap causing an error in executing the hash operation.
Fix this by using a u64 type for the input and output data lengths in
all CCP operations.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

4 files changed, 53 insertions, 33 deletions

diff --git a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
index c6b8f9e56aab..a52b97a4c843 100644
--- a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
+++ b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
@@ -37,8 +37,9 @@ static int ccp_aes_cmac_complete(struct crypto_async_request *async_req,
 
         if (rctx->hash_rem) {
                 /* Save remaining data to buffer */
-                scatterwalk_map_and_copy(rctx->buf, rctx->cmd.u.aes.src,
-                                         rctx->hash_cnt, rctx->hash_rem, 0);
+                unsigned int offset = rctx->nbytes - rctx->hash_rem;
+                scatterwalk_map_and_copy(rctx->buf, rctx->src,
+                                         offset, rctx->hash_rem, 0);
                 rctx->buf_count = rctx->hash_rem;
         } else
                 rctx->buf_count = 0;
@@ -62,8 +63,9 @@ static int ccp_do_cmac_update(struct ahash_request *req, unsigned int nbytes,
         struct scatterlist *sg, *cmac_key_sg = NULL;
         unsigned int block_size =
                 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
-        unsigned int len, need_pad, sg_count;
+        unsigned int need_pad, sg_count;
         gfp_t gfp;
+        u64 len;
         int ret;
 
         if (!ctx->u.aes.key_len)
@@ -72,7 +74,9 @@ static int ccp_do_cmac_update(struct ahash_request *req, unsigned int nbytes,
         if (nbytes)
                 rctx->null_msg = 0;
 
-        if (!final && ((nbytes + rctx->buf_count) <= block_size)) {
+        len = (u64)rctx->buf_count + (u64)nbytes;
+
+        if (!final && (len <= block_size)) {
                 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
                                          0, nbytes, 0);
                 rctx->buf_count += nbytes;
@@ -80,12 +84,13 @@ static int ccp_do_cmac_update(struct ahash_request *req, unsigned int nbytes,
                 return 0;
         }
 
-        len = rctx->buf_count + nbytes;
+        rctx->src = req->src;
+        rctx->nbytes = nbytes;
 
         rctx->final = final;
-        rctx->hash_cnt = final ? len : len & ~(block_size - 1);
-        rctx->hash_rem = final ?   0 : len &  (block_size - 1);
-        if (!final && (rctx->hash_cnt == len)) {
+        rctx->hash_rem = final ? 0 : len & (block_size - 1);
+        rctx->hash_cnt = len - rctx->hash_rem;
+        if (!final && !rctx->hash_rem) {
                 /* CCP can't do zero length final, so keep some data around */
                 rctx->hash_cnt -= block_size;
                 rctx->hash_rem = block_size;
diff --git a/drivers/crypto/ccp/ccp-crypto-sha.c b/drivers/crypto/ccp/ccp-crypto-sha.c
index 183d16e46d20..d30f6c893ffb 100644
--- a/drivers/crypto/ccp/ccp-crypto-sha.c
+++ b/drivers/crypto/ccp/ccp-crypto-sha.c
@@ -101,8 +101,9 @@ static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
 
         if (rctx->hash_rem) {
                 /* Save remaining data to buffer */
-                scatterwalk_map_and_copy(rctx->buf, rctx->cmd.u.sha.src,
-                                         rctx->hash_cnt, rctx->hash_rem, 0);
+                unsigned int offset = rctx->nbytes - rctx->hash_rem;
+                scatterwalk_map_and_copy(rctx->buf, rctx->src,
+                                         offset, rctx->hash_rem, 0);
                 rctx->buf_count = rctx->hash_rem;
         } else
                 rctx->buf_count = 0;
@@ -129,11 +130,14 @@ static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
         struct scatterlist *sg;
         unsigned int block_size =
                 crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
-        unsigned int len, sg_count;
+        unsigned int sg_count;
         gfp_t gfp;
+        u64 len;
         int ret;
 
-        if (!final && ((nbytes + rctx->buf_count) <= block_size)) {
+        len = (u64)rctx->buf_count + (u64)nbytes;
+
+        if (!final && (len <= block_size)) {
                 scatterwalk_map_and_copy(rctx->buf + rctx->buf_count, req->src,
                                          0, nbytes, 0);
                 rctx->buf_count += nbytes;
@@ -141,12 +145,13 @@ static int ccp_do_sha_update(struct ahash_request *req, unsigned int nbytes,
                 return 0;
         }
 
-        len = rctx->buf_count + nbytes;
+        rctx->src = req->src;
+        rctx->nbytes = nbytes;
 
         rctx->final = final;
-        rctx->hash_cnt = final ? len : len & ~(block_size - 1);
-        rctx->hash_rem = final ?   0 : len &  (block_size - 1);
-        if (!final && (rctx->hash_cnt == len)) {
+        rctx->hash_rem = final ? 0 : len & (block_size - 1);
+        rctx->hash_cnt = len - rctx->hash_rem;
+        if (!final && !rctx->hash_rem) {
                 /* CCP can't do zero length final, so keep some data around */
                 rctx->hash_cnt -= block_size;
                 rctx->hash_rem = block_size;
diff --git a/drivers/crypto/ccp/ccp-crypto.h b/drivers/crypto/ccp/ccp-crypto.h
index 13ea6ea4b45d..b222231b6169 100644
--- a/drivers/crypto/ccp/ccp-crypto.h
+++ b/drivers/crypto/ccp/ccp-crypto.h
@@ -110,7 +110,10 @@ struct ccp_aes_cmac_req_ctx {
         unsigned int null_msg;
         unsigned int final;
 
-        unsigned int hash_cnt;
+        struct scatterlist *src;
+        unsigned int nbytes;
+
+        u64 hash_cnt;
         unsigned int hash_rem;
 
         struct sg_table data_sg;
@@ -149,7 +152,10 @@ struct ccp_sha_req_ctx {
         unsigned int first;
         unsigned int final;
 
-        unsigned int hash_cnt;
+        struct scatterlist *src;
+        unsigned int nbytes;
+
+        u64 hash_cnt;
         unsigned int hash_rem;
 
         struct sg_table data_sg;
diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
index 4be091037549..71ed3ade7e12 100644
--- a/drivers/crypto/ccp/ccp-ops.c
+++ b/drivers/crypto/ccp/ccp-ops.c
@@ -60,9 +60,9 @@ struct ccp_sg_workarea {
         unsigned int dma_count;
         enum dma_data_direction dma_dir;
 
-        u32 sg_used;
+        unsigned int sg_used;
 
-        u32 bytes_left;
+        u64 bytes_left;
 };
 
 struct ccp_data {
@@ -466,7 +466,7 @@ static void ccp_sg_free(struct ccp_sg_workarea *wa)
 }
 
 static int ccp_init_sg_workarea(struct ccp_sg_workarea *wa, struct device *dev,
-                                struct scatterlist *sg, unsigned int len,
+                                struct scatterlist *sg, u64 len,
                                 enum dma_data_direction dma_dir)
 {
         memset(wa, 0, sizeof(*wa));
@@ -499,7 +499,7 @@ static int ccp_init_sg_workarea(struct ccp_sg_workarea *wa, struct device *dev,
 
 static void ccp_update_sg_workarea(struct ccp_sg_workarea *wa, unsigned int len)
 {
-        unsigned int nbytes = min(len, wa->bytes_left);
+        unsigned int nbytes = min_t(u64, len, wa->bytes_left);
 
         if (!wa->sg)
                 return;
@@ -653,7 +653,7 @@ static void ccp_free_data(struct ccp_data *data, struct ccp_cmd_queue *cmd_q)
 }
 
 static int ccp_init_data(struct ccp_data *data, struct ccp_cmd_queue *cmd_q,
-                         struct scatterlist *sg, unsigned int sg_len,
+                         struct scatterlist *sg, u64 sg_len,
                          unsigned int dm_len,
                          enum dma_data_direction dir)
 {
@@ -691,17 +691,20 @@ static unsigned int ccp_queue_buf(struct ccp_data *data, unsigned int from)
         if (!sg_wa->sg)
                 return 0;
 
-        /* Perform the copy operation */
-        nbytes = min(sg_wa->bytes_left, dm_wa->length);
+        /* Perform the copy operation
+         *   nbytes will always be <= UINT_MAX because dm_wa->length is
+         *   an unsigned int
+         */
+        nbytes = min_t(u64, sg_wa->bytes_left, dm_wa->length);
         scatterwalk_map_and_copy(dm_wa->address, sg_wa->sg, sg_wa->sg_used,
                                  nbytes, from);
 
         /* Update the structures and generate the count */
         buf_count = 0;
         while (sg_wa->bytes_left && (buf_count < dm_wa->length)) {
-                nbytes = min3(sg_wa->sg->length - sg_wa->sg_used,
-                              dm_wa->length - buf_count,
-                              sg_wa->bytes_left);
+                nbytes = min(sg_wa->sg->length - sg_wa->sg_used,
+                             dm_wa->length - buf_count);
+                nbytes = min_t(u64, sg_wa->bytes_left, nbytes);
 
                 buf_count += nbytes;
                 ccp_update_sg_workarea(sg_wa, nbytes);
@@ -728,14 +731,15 @@ static void ccp_prepare_data(struct ccp_data *src, struct ccp_data *dst,
 
         /* The CCP can only DMA from/to one address each per operation. This
          * requires that we find the smallest DMA area between the source
-         * and destination.
+         * and destination. The resulting len values will always be <= UINT_MAX
+         * because the dma length is an unsigned int.
          */
-        sg_src_len = min(sg_dma_len(src->sg_wa.sg) - src->sg_wa.sg_used,
-                         src->sg_wa.bytes_left);
+        sg_src_len = sg_dma_len(src->sg_wa.sg) - src->sg_wa.sg_used;
+        sg_src_len = min_t(u64, src->sg_wa.bytes_left, sg_src_len);
 
         if (dst) {
-                sg_dst_len = min(sg_dma_len(dst->sg_wa.sg) - dst->sg_wa.sg_used,
-                                 src->sg_wa.bytes_left);
+                sg_dst_len = sg_dma_len(dst->sg_wa.sg) - dst->sg_wa.sg_used;
+                sg_dst_len = min_t(u64, src->sg_wa.bytes_left, sg_dst_len);
                 op_len = min(sg_src_len, sg_dst_len);
         } else
                 op_len = sg_src_len;