[PATCH net] net: dsa: microchip: Fix error path in PTP IRQ setup

[Bastien Curutchet (Schneider Electric)]

If request_threaded_irq() fails during the PTP message IRQ setup, the
newly created IRQ mapping is never disposed. Indeed, the
ksz_ptp_irq_setup()'s error path only frees the mappings that were
successfully set up.

Dispose the newly created mapping if the associated
request_threaded_irq() fails at setup.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: d0b8fec8ae505 ("net: dsa: microchip: Fix symetry in ksz_ptp_msg_irq_{setup/free}()")
Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@xxxxxxxxxxx>
---
 drivers/net/dsa/microchip/ksz_ptp.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c
index 4a2cc57a628f97bd51fcb11057bc4effda9205dd..8b98039320adda7655ae2563b896b92033d2f1ad 100644
--- a/drivers/net/dsa/microchip/ksz_ptp.c
+++ b/drivers/net/dsa/microchip/ksz_ptp.c
@@ -1108,6 +1108,7 @@ static int ksz_ptp_msg_irq_setup(struct ksz_port *port, u8 n)
 	const struct ksz_dev_ops *ops = port->ksz_dev->dev_ops;
 	struct ksz_irq *ptpirq = &port->ptpirq;
 	struct ksz_ptp_irq *ptpmsg_irq;
+	int ret;
 
 	ptpmsg_irq = &port->ptpmsg_irq[n];
 	ptpmsg_irq->num = irq_create_mapping(ptpirq->domain, n);
@@ -1119,9 +1120,13 @@ static int ksz_ptp_msg_irq_setup(struct ksz_port *port, u8 n)
 
 	strscpy(ptpmsg_irq->name, name[n]);
 
-	return request_threaded_irq(ptpmsg_irq->num, NULL,
-				    ksz_ptp_msg_thread_fn, IRQF_ONESHOT,
-				    ptpmsg_irq->name, ptpmsg_irq);
+	ret = request_threaded_irq(ptpmsg_irq->num, NULL,
+				   ksz_ptp_msg_thread_fn, IRQF_ONESHOT,
+				   ptpmsg_irq->name, ptpmsg_irq);
+	if (ret)
+		irq_dispose_mapping(ptpmsg_irq->num);
+
+	return ret;
 }
 
 int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p)

---
base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
change-id: 20260306-ksz-ptp-irq-fix-3d1d6ccb4ade

Best regards,
-- 
Bastien Curutchet (Schneider Electric) <bastien.curutchet@xxxxxxxxxxx>