[dpdk-stable] [PATCH 3/3] common/sfc_efx/base: enhance field ID check in field set API

[Ivan Malov <ivan.malov@oktetlabs.ru>]

A field ID passed to the API may point to a gap in the array
of field descriptors. Turn down such invocations as improper.

Fixes: 370ed675a952 ("common/sfc_efx/base: support setting PPORT in match spec")
Cc: stable@dpdk.org

Reviewed-by: Andy Moreton <amoreton@xilinx.com>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
---
 drivers/common/sfc_efx/base/efx_mae.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/common/sfc_efx/base/efx_mae.c b/drivers/common/sfc_efx/base/efx_mae.c
index c1717d7b0..f4a529f5a 100644
--- a/drivers/common/sfc_efx/base/efx_mae.c
+++ b/drivers/common/sfc_efx/base/efx_mae.c
@@ -678,16 +678,22 @@ efx_mae_match_spec_field_set(
 		goto fail2;
 	}
 
-	if (value_size != descp->emmd_value_size) {
+	if (descp->emmd_mask_size == 0) {
+		/* The ID points to a gap in the array of field descriptors. */
 		rc = EINVAL;
 		goto fail3;
 	}
 
-	if (mask_size != descp->emmd_mask_size) {
+	if (value_size != descp->emmd_value_size) {
 		rc = EINVAL;
 		goto fail4;
 	}
 
+	if (mask_size != descp->emmd_mask_size) {
+		rc = EINVAL;
+		goto fail5;
+	}
+
 	if (descp->emmd_endianness == EFX_MAE_FIELD_BE) {
 		/*
 		 * The mask/value are in network (big endian) order.
@@ -729,6 +735,8 @@ efx_mae_match_spec_field_set(
 
 	return (0);
 
+fail5:
+	EFSYS_PROBE(fail5);
 fail4:
 	EFSYS_PROBE(fail4);
 fail3:
-- 
2.20.1