The EIP97 hardware cannot handle zero length input data and will (usually)
hang when presented with this anyway. This patch converts any zero length
input to a 1 byte dummy input to prevent this hanging.
Signed-off-by: Pascal van Leeuwen <pvanleeuwen@xxxxxxxxxx>
---
drivers/crypto/inside-secure/safexcel_cipher.c | 40 ++++++++++++++------------
1 file changed, 22 insertions(+), 18 deletions(-)
diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/crypto/inside-secure/safexcel_cipher.c
index b76f5ab..db26166 100644
--- a/drivers/crypto/inside-secure/safexcel_cipher.c
+++ b/drivers/crypto/inside-secure/safexcel_cipher.c
@@ -782,16 +782,31 @@ static int safexcel_send_req(struct crypto_async_request *base, int ring,
memcpy(ctx->base.ctxr->data, ctx->key, ctx->key_len);
- /* The EIP cannot deal with zero length input packets! */
- if (totlen == 0)
- totlen = 1;
+ if (!totlen) {
+ /*
+ * The EIP97 cannot deal with zero length input packets!
+ * So stuff a dummy command descriptor indicating a 1 byte
+ * (dummy) input packet, using the context record as source.
+ */
+ first_cdesc = safexcel_add_cdesc(priv, ring,
+ 1, 1, ctx->base.ctxr_dma,
+ 1, 1, ctx->base.ctxr_dma,
+ &atoken);
+ if (IS_ERR(first_cdesc)) {
+ /* No space left in the command descriptor ring */
+ ret = PTR_ERR(first_cdesc);
+ goto cdesc_rollback;
+ }
+ n_cdesc = 1;
+ goto skip_cdesc;
+ }
/* command descriptors */
for_each_sg(src, sg, sreq->nr_src, i) {
int len = sg_dma_len(sg);
/* Do not overflow the request */
- if (queued - len < 0)
+ if (queued < len)
len = queued;
cdesc = safexcel_add_cdesc(priv, ring, !n_cdesc,
@@ -803,27 +818,16 @@ static int safexcel_send_req(struct crypto_async_request *base, int ring,
ret = PTR_ERR(cdesc);
goto cdesc_rollback;
}
- n_cdesc++;
- if (n_cdesc == 1) {
+ if (!n_cdesc)
first_cdesc = cdesc;
- }
+ n_cdesc++;
queued -= len;
if (!queued)
break;
}
-
- if (unlikely(!n_cdesc)) {
- /*
- * Special case: zero length input buffer.
- * The engine always needs the 1st command descriptor, however!
- */
- first_cdesc = safexcel_add_cdesc(priv, ring, 1, 1, 0, 0, totlen,
- ctx->base.ctxr_dma, &atoken);
- n_cdesc = 1;
- }
-
+skip_cdesc:
/* Add context control words and token to first command descriptor */
safexcel_context_control(ctx, base, sreq, first_cdesc);
if (ctx->aead)
--
1.8.3.1
