[dpdk-dev] [PATCH] net/sfc: ignore spec bits not covered by mask

[Andrew Rybchenko <arybchenko@solarflare.com>]

mask is a simple bit-mask applied before interpreting the contents
of spec and last.

Fixes: a9825ccf5bb8 ("net/sfc: support flow API filters")
Cc: stable@dpdk.org

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Andy Moreton <amoreton@solarflare.com>
Reviewed-by: Roman Zhukov <roman.zhukov@oktetlabs.ru>
---
 drivers/net/sfc/sfc_flow.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/sfc/sfc_flow.c b/drivers/net/sfc/sfc_flow.c
index fe4c0b0c5..efa9bac8d 100644
--- a/drivers/net/sfc/sfc_flow.c
+++ b/drivers/net/sfc/sfc_flow.c
@@ -119,7 +119,6 @@ sfc_flow_parse_init(const struct rte_flow_item *item,
 	const uint8_t *spec;
 	const uint8_t *mask;
 	const uint8_t *last;
-	uint8_t match;
 	uint8_t supp;
 	unsigned int i;
 
@@ -180,12 +179,11 @@ sfc_flow_parse_init(const struct rte_flow_item *item,
 		return -rte_errno;
 	}
 
-	/* Check that mask and spec not asks for more match than supp_mask */
+	/* Check that mask does not ask for more match than supp_mask */
 	for (i = 0; i < size; i++) {
-		match = spec[i] | mask[i];
 		supp = ((const uint8_t *)supp_mask)[i];
 
-		if ((match | supp) != supp) {
+		if (~supp & mask[i]) {
 			rte_flow_error_set(error, ENOTSUP,
 					   RTE_FLOW_ERROR_TYPE_ITEM, item,
 					   "Item's field is not supported");
-- 
2.14.1