[dpdk-dev] [PATCH 1/2] net/bnxt: fix to return count in xstats get op in all cases

[Somnath Kotur]

Driver was returning 0 if the 'xstats' parameter being passed to
xstats_get_op was NULL. This won't work on some applications that
rely on a valid count being passed even in this case so that it can
allocate memory accordingly followed by a reissue of the xstats_get_op
to get the actual stats populated by the driver.

Fixes: 063e59ddd28 ("net/bnxt: fix crash in xstats get")
Cc: stable at dpdk.org

Reviewed-by: Kalesh Anakkur Purayil <kalesh-anakkur.purayil at broadcom.com>
Reviewed-by: Lance Richardson <lance.richardson at broadcom.com>
Signed-off-by: Somnath Kotur <somnath.kotur at broadcom.com>
---
 drivers/net/bnxt/bnxt_stats.c | 23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

diff --git a/drivers/net/bnxt/bnxt_stats.c b/drivers/net/bnxt/bnxt_stats.c
index 01d90dee8d..bb4b2eee19 100644
--- a/drivers/net/bnxt/bnxt_stats.c
+++ b/drivers/net/bnxt/bnxt_stats.c
@@ -594,10 +594,15 @@ int bnxt_dev_xstats_get_op(struct rte_eth_dev *eth_dev,
 	if (rc)
 		return rc;
 
-	if (xstats == NULL)
-		return 0;
+	stat_count = RTE_DIM(bnxt_rx_stats_strings) +
+		RTE_DIM(bnxt_tx_stats_strings) +
+		RTE_DIM(bnxt_func_stats_strings) +
+		RTE_DIM(bnxt_rx_ext_stats_strings) +
+		RTE_DIM(bnxt_tx_ext_stats_strings) +
+		bnxt_flow_stats_cnt(bp);
 
-	memset(xstats, 0, sizeof(*xstats));
+	if (n < stat_count || xstats == NULL)
+		return stat_count;
 
 	bnxt_hwrm_func_qstats(bp, 0xffff, NULL, &func_qstats);
 	bnxt_hwrm_port_qstats(bp);
@@ -609,17 +614,7 @@ int bnxt_dev_xstats_get_op(struct rte_eth_dev *eth_dev,
 					(bp->fw_tx_port_stats_ext_size /
 					 stat_size));
 
-	count = RTE_DIM(bnxt_rx_stats_strings) +
-		RTE_DIM(bnxt_tx_stats_strings) +
-		RTE_DIM(bnxt_func_stats_strings) +
-		RTE_DIM(bnxt_rx_ext_stats_strings) +
-		RTE_DIM(bnxt_tx_ext_stats_strings) +
-		bnxt_flow_stats_cnt(bp);
-
-	stat_count = count;
-
-	if (n < count)
-		return count;
+	memset(xstats, 0, sizeof(*xstats));
 
 	count = 0;
 	for (i = 0; i < RTE_DIM(bnxt_rx_stats_strings); i++) {
-- 
2.28.0.497.g54e85e7