patch 'net/nbl: fix mbuf double-free in queue cleanup' has been queued to stable release 25.11.1

[Kevin Traynor]

Hi,

FYI, your patch has been queued to stable release 25.11.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 03/02/26. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/kevintraynor/dpdk-stable

This queued commit can be viewed at:
https://github.com/kevintraynor/dpdk-stable/commit/a87c0e826b1a0d2cc725e3058cfc6cfdb98dbe05

Thanks.

Kevin

---
>From a87c0e826b1a0d2cc725e3058cfc6cfdb98dbe05 Mon Sep 17 00:00:00 2001
From: Dimon Zhao <dimon.zhao at nebula-matrix.com>
Date: Mon, 26 Jan 2026 18:52:19 -0800
Subject: [PATCH] net/nbl: fix mbuf double-free in queue cleanup

[ upstream commit 43ed974c6976af0df3383ca0d793021204a1a1f3 ]

Only free hardware-owned mbufs to avoid double-free
corruption of application-owned buffers.

TX ring: free only transmitted mbufs (next_to_clean to next_to_use).
RX ring: free only allocated receive buffers
	 (next_to_clean to next_to_use),
	 mbufs already delivered to the application (before next_to_clean)
	 must not be touched.

Fixes: 5d910b2789da ("net/nbl: support queue setup and release")

Signed-off-by: Dimon Zhao <dimon.zhao at nebula-matrix.com>
---
 drivers/net/nbl/nbl_dev/nbl_dev.c     |  2 +-
 drivers/net/nbl/nbl_hw/nbl_txrx.c     | 73 ++++++++++++++++++++++-----
 drivers/net/nbl/nbl_hw/nbl_txrx_ops.h |  2 +-
 3 files changed, 61 insertions(+), 16 deletions(-)

diff --git a/drivers/net/nbl/nbl_dev/nbl_dev.c b/drivers/net/nbl/nbl_dev/nbl_dev.c
index 8a56939aa7..6ebd40ed5d 100644
--- a/drivers/net/nbl/nbl_dev/nbl_dev.c
+++ b/drivers/net/nbl/nbl_dev/nbl_dev.c
@@ -275,6 +275,6 @@ int nbl_dev_port_stop(struct rte_eth_dev *eth_dev)
 
 	nbl_dev_hw_stats_stop(eth_dev);
-	nbl_clear_queues(eth_dev);
 	nbl_dev_txrx_stop(eth_dev);
+	nbl_clear_queues(eth_dev);
 	nbl_userdev_port_config(adapter, NBL_KERNEL_NETWORK);
 	return 0;
diff --git a/drivers/net/nbl/nbl_hw/nbl_txrx.c b/drivers/net/nbl/nbl_hw/nbl_txrx.c
index 93d9f0f7de..48f20e4f4c 100644
--- a/drivers/net/nbl/nbl_hw/nbl_txrx.c
+++ b/drivers/net/nbl/nbl_hw/nbl_txrx.c
@@ -45,17 +45,41 @@ static void nbl_res_txrx_stop_tx_ring(void *priv, u16 queue_idx)
 	struct nbl_resource_mgt *res_mgt = (struct nbl_resource_mgt *)priv;
 	struct nbl_res_tx_ring *tx_ring = NBL_RES_MGT_TO_TX_RING(res_mgt, queue_idx);
-	int i;
+	struct nbl_tx_entry *tx_entry;
+	u16 i, free_cnt, free_mbuf_cnt;
 
 	if (!tx_ring)
 		return;
 
+	i = tx_ring->next_to_clean + 1 - NBL_TX_RS_THRESH;
+	free_cnt = tx_ring->vq_free_cnt;
+	tx_entry = &tx_ring->tx_entry[i];
+	free_mbuf_cnt = 0;
+
+	while (free_cnt < tx_ring->nb_desc) {
+		if (tx_entry->mbuf) {
+			free_mbuf_cnt++;
+			rte_pktmbuf_free_seg(tx_entry->mbuf);
+		}
+
+		i++;
+		tx_entry++;
+		free_cnt++;
+		if (i == tx_ring->nb_desc) {
+			i = 0;
+			tx_entry = &tx_ring->tx_entry[i];
+		}
+	}
+
+	NBL_LOG(DEBUG, "stop tx ring ntc %u, ntu %u, vq_free_cnt %u, mbuf free_cnt %u",
+		tx_ring->next_to_clean, tx_ring->next_to_use, tx_ring->vq_free_cnt, free_mbuf_cnt);
+
 	for (i = 0; i < tx_ring->nb_desc; i++) {
-		if (tx_ring->tx_entry[i].mbuf != NULL) {
-			rte_pktmbuf_free_seg(tx_ring->tx_entry[i].mbuf);
-			memset(&tx_ring->tx_entry[i], 0, sizeof(*tx_ring->tx_entry));
-		}
+		tx_ring->desc[i].addr = 0;
+		tx_ring->desc[i].len = 0;
+		tx_ring->desc[i].id = 0;
 		tx_ring->desc[i].flags = 0;
 	}
 
+	memset(tx_ring->tx_entry, 0, sizeof(*tx_entry) * tx_ring->nb_desc);
 	tx_ring->avail_used_flags = NBL_PACKED_DESC_F_AVAIL_BIT;
 	tx_ring->used_wrap_counter = 1;
@@ -209,23 +233,44 @@ static void nbl_res_txrx_stop_rx_ring(void *priv, u16 queue_idx)
 {
 	struct nbl_resource_mgt *res_mgt = (struct nbl_resource_mgt *)priv;
-	struct nbl_res_rx_ring *rx_ring =
-			NBL_RES_MGT_TO_RX_RING(res_mgt, queue_idx);
-	u16 i;
+	struct nbl_res_rx_ring *rx_ring = NBL_RES_MGT_TO_RX_RING(res_mgt, queue_idx);
+	struct nbl_rx_entry *rx_buf;
+	u16 i, free_cnt, free_mbuf_cnt;
 
 	if (!rx_ring)
 		return;
+
+	i = rx_ring->next_to_clean;
+	free_cnt = rx_ring->vq_free_cnt;
+	free_mbuf_cnt = 0;
+
 	if (rx_ring->rx_entry != NULL) {
-		for (i = 0; i < rx_ring->nb_desc; i++) {
-			if (rx_ring->rx_entry[i].mbuf != NULL) {
-				rte_pktmbuf_free_seg(rx_ring->rx_entry[i].mbuf);
-				rx_ring->rx_entry[i].mbuf = NULL;
+		rx_buf = &rx_ring->rx_entry[i];
+		while (free_cnt < rx_ring->nb_desc) {
+			if (rx_buf->mbuf) {
+				free_mbuf_cnt++;
+				rte_pktmbuf_free_seg(rx_buf->mbuf);
+			}
+
+			i++;
+			rx_buf++;
+			free_cnt++;
+			if (i == rx_ring->nb_desc) {
+				i = 0;
+				rx_buf = &rx_ring->rx_entry[i];
 			}
-			rx_ring->desc[i].flags = 0;
 		}
 
-		for (i = rx_ring->nb_desc; i < rx_ring->nb_desc + NBL_DESC_PER_LOOP_VEC_MAX; i++)
+		memset(rx_ring->rx_entry, 0, sizeof(struct nbl_rx_entry) * rx_ring->nb_desc);
+
+		for (i = 0; i < rx_ring->nb_desc + NBL_DESC_PER_LOOP_VEC_MAX; i++) {
+			rx_ring->desc[i].addr = 0;
+			rx_ring->desc[i].len = 0;
+			rx_ring->desc[i].id = 0;
 			rx_ring->desc[i].flags = 0;
+		}
 	}
 
+	NBL_LOG(DEBUG, "stop rx ring ntc %u, ntu %u, vq_free_cnt %u, free_mbuf_cnt %u",
+		rx_ring->next_to_clean, rx_ring->next_to_use, rx_ring->vq_free_cnt, free_mbuf_cnt);
 	rx_ring->next_to_clean = 0;
 	rx_ring->next_to_use = 0;
diff --git a/drivers/net/nbl/nbl_hw/nbl_txrx_ops.h b/drivers/net/nbl/nbl_hw/nbl_txrx_ops.h
index 2ab4b09683..dc0bab2b7b 100644
--- a/drivers/net/nbl/nbl_hw/nbl_txrx_ops.h
+++ b/drivers/net/nbl/nbl_hw/nbl_txrx_ops.h
@@ -44,5 +44,5 @@ nbl_tx_free_bufs(struct nbl_res_tx_ring *txq)
 		return 0;
 
-	n = 32;
+	n = NBL_TX_RS_THRESH;
 
 	 /* first buffer to free from S/W ring is at index
-- 
2.53.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2026-02-26 10:16:50.711041841 +0000
+++ 0093-net-nbl-fix-mbuf-double-free-in-queue-cleanup.patch	2026-02-26 10:16:47.037615297 +0000
@@ -1 +1 @@
-From 43ed974c6976af0df3383ca0d793021204a1a1f3 Mon Sep 17 00:00:00 2001
+From a87c0e826b1a0d2cc725e3058cfc6cfdb98dbe05 Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit 43ed974c6976af0df3383ca0d793021204a1a1f3 ]
+
@@ -16 +17,0 @@
-Cc: stable at dpdk.org