[PATCH net-next v14 2/4] ptp: ocp: fix dpll cleanup on probe error

[Sagi Maimon <maimon.sagi@gmail.com>]

Two problems on the dpll error paths in ptp_ocp_probe().

dpll_device_register() takes a second reference and stores bp as the
registration private data, and only dpll_device_unregister() drops it.
out_dpll dropped bp->tracker but never unregistered, so a dpll_pin_get()
or dpll_pin_register() failure left the device registered and visible to
userspace with a priv pointer into the storage devlink_free() releases a
few lines later, as well as leaking the registration object.

A failing dpll_device_register() jumped to the same label as the failing
dpll_device_get(), so the reference taken by dpll_device_get() was never
dropped either.  Give that case its own label.

Fixes: 09eeb3aecc6c ("ptp_ocp: implement DPLL ops")
Signed-off-by: Sagi Maimon <maimon.sagi@gmail.com>
---
 drivers/ptp/ptp_ocp.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c
index 401b04f12d2b..f4299878c27c 100644
--- a/drivers/ptp/ptp_ocp.c
+++ b/drivers/ptp/ptp_ocp.c
@@ -5124,7 +5124,7 @@ ptp_ocp_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	err = dpll_device_register(bp->dpll, DPLL_TYPE_PPS, &dpll_ops, bp);
 	if (err)
-		goto out_devlink;
+		goto out_dpll_put;
 
 	for (i = 0; i < OCP_SMA_NUM; i++) {
 		bp->sma[i].dpll_pin = dpll_pin_get(clkid, i, THIS_MODULE,
@@ -5150,6 +5150,12 @@ ptp_ocp_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		dpll_pin_unregister(bp->dpll, bp->sma[i].dpll_pin, &dpll_pins_ops, &bp->sma[i]);
 		dpll_pin_put(bp->sma[i].dpll_pin, &bp->sma[i].tracker);
 	}
+	/* dpll_device_register() takes a second reference and stores bp; only
+	 * dpll_device_unregister() drops it.  Without this the device stays
+	 * visible with a priv pointer into storage devlink_free() will release.
+	 */
+	dpll_device_unregister(bp->dpll, &dpll_ops, bp);
+out_dpll_put:
 	dpll_device_put(bp->dpll, &bp->tracker);
 out_devlink:
 	devlink_unregister(devlink);
-- 
2.47.0