net: dsa: microchip: Don't free uninitialized ksz_irq

If something goes wrong at setup, ksz_irq_free() can be called on
uninitialized ksz_irq (for example when ksz_ptp_irq_setup() fails). It
leads to freeing uninitialized IRQ numbers and/or domains.

Use dsa_switch_for_each_user_port_continue_reverse() in the error path
to iterate only over the fully initialized ports.

Cc: stable@vger.kernel.org
Fixes: cc13ab18b201 ("net: dsa: microchip: ptp: enable interrupt for timestamping")
Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@bootlin.com>
Link: https://patch.msgid.link/20251120-ksz-fix-v6-3-891f80ae7f8f@bootlin.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index e684568a4edad68ae93712c0d5604958a08116d0..a927055423f3bcbe29508b32cf10f1a0704c5938 100644 (file)
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3082,7 +3082,7 @@ out_ptpirq:
                        ksz_ptp_irq_free(ds, dp->index);
 out_pirq:
        if (dev->irq > 0)
-               dsa_switch_for_each_user_port(dp, dev->ds)
+               dsa_switch_for_each_user_port_continue_reverse(dp, dev->ds)
                        ksz_irq_free(&dev->ports[dp->index].pirq);
 out_girq:
        if (dev->irq > 0)