[PATCH v3] tg3: clean up PHYLIB resources on probe failure

[Myeonghun Pak]

tg3_get_invariants() can register an MDIO bus and connect a PHY for
USE_PHYLIB devices. If tg3_init_one() later fails, its common error path
releases the mappings and netdev without undoing those PHYLIB resources.

Disconnect the PHY and unregister the MDIO bus before the remaining
teardown. Guard PHY cleanup with USE_PHYLIB to match tg3_phy_init(), and
call tg3_mdio_fini() unconditionally to match tg3_mdio_init(). The existing
IS_CONNECTED and MDIOBUS_INITED flags make both helpers safe when
initialization only completed partially.

This issue was identified during our ongoing static-analysis research while
reviewing kernel code.

Fixes: 158d7abdae85 ("tg3: Add mdio bus registration")
Assisted-by: OpenAI:GPT-5.6
Co-developed-by: Ijae Kim <ae878000@xxxxxxxxx>
Signed-off-by: Ijae Kim <ae878000@xxxxxxxxx>
Signed-off-by: Myeonghun Pak <mhun512@xxxxxxxxx>
---
Changes in v3:
- Restore the USE_PHYLIB guard around tg3_phy_fini() to match
  tg3_phy_init(), while keeping tg3_mdio_fini() unconditional, as
  clarified by Andrew Lunn.

Changes in v2:
- Removed the USE_PHYLIB guard around both cleanup calls. This
  misinterpreted Andrew Lunn's feedback and is corrected in v3.

 drivers/net/ethernet/broadcom/tg3.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 73a4b569b..caa7a6caa 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -18047,6 +18047,10 @@ static int tg3_init_one(struct pci_dev *pdev,
 	return 0;
 
 err_out_apeunmap:
+	if (tg3_flag(tp, USE_PHYLIB))
+		tg3_phy_fini(tp);
+	tg3_mdio_fini(tp);
+
 	if (tp->aperegs) {
 		iounmap(tp->aperegs);
 		tp->aperegs = NULL;
-- 
2.47.1