[PATCH v2 2/5] net/failsafe: fix queue release without sub-device op

[Sandeep Penigalapati]

fs_rx_queue_release() and fs_tx_queue_release() iterate over the active
sub-devices and call the sub-device Rx/Tx queue release op directly.
Some PMDs do not implement that op, so the function pointer is NULL.
Calling it unconditionally could dereference a NULL pointer and crash
when releasing fail-safe queues.

Check that the sub-device provides the release op before calling it.

Fixes: 7483341ae553 ("ethdev: change queue release callback")
Cc: stable at dpdk.org
Signed-off-by: Sandeep Penigalapati <sandeep.penigalapati at intel.com>
---
v2:
- Add explicit ETH(sdev) != NULL check before dereferencing.

 drivers/net/failsafe/failsafe_ops.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/failsafe/failsafe_ops.c b/drivers/net/failsafe/failsafe_ops.c
index 8761cb07c3..0b025bd122 100644
--- a/drivers/net/failsafe/failsafe_ops.c
+++ b/drivers/net/failsafe/failsafe_ops.c
@@ -398,7 +398,9 @@ fs_rx_queue_release(struct rte_eth_dev *dev, uint16_t qid)
 	if (rxq->event_fd >= 0)
 		close(rxq->event_fd);
 	FOREACH_SUBDEV_STATE(sdev, i, dev, DEV_ACTIVE) {
-		if (ETH(sdev)->data->rx_queues != NULL &&
+		if (ETH(sdev) != NULL &&
+		    SUBOPS(sdev, rx_queue_release) != NULL &&
+		    ETH(sdev)->data->rx_queues != NULL &&
 		    ETH(sdev)->data->rx_queues[rxq->qid] != NULL)
 			SUBOPS(sdev, rx_queue_release)(ETH(sdev), rxq->qid);
 	}
@@ -574,7 +576,9 @@ fs_tx_queue_release(struct rte_eth_dev *dev, uint16_t qid)
 	if (fs_lock(dev, 0) != 0)
 		return;
 	FOREACH_SUBDEV_STATE(sdev, i, dev, DEV_ACTIVE) {
-		if (ETH(sdev)->data->tx_queues != NULL &&
+		if (ETH(sdev) != NULL &&
+		    SUBOPS(sdev, tx_queue_release) != NULL &&
+		    ETH(sdev)->data->tx_queues != NULL &&
 		    ETH(sdev)->data->tx_queues[txq->qid] != NULL)
 			SUBOPS(sdev, tx_queue_release)(ETH(sdev), txq->qid);
 	}
-- 
2.34.1