+ Andrew Lunn, Diogo Ivo, Vignesh Raghavendra Not trimming reply to provide context for these people

On Tue, May 21, 2024 at 02:44:11PM +0200, Romain Gantois wrote:

In the prueth_probe() function, if one of the calls to emac_phy_connect() fails due to of_phy_connect() returning NULL, then the subsequent call to phy_attached_info() will dereference a NULL pointer.

Check the return code of emac_phy_connect and fail cleanly if there is an error.

Fixes: 128d5874c082 ("net: ti: icssg-prueth: Add ICSSG ethernet driver") Cc: stable@vger.kernel.org Signed-off-by: Romain Gantois romain.gantois@bootlin.com

For Networking patches, please consider seeding the CC list using ./scripts/get_maintainer.pl this.patch. I've added the people who seemed to be missing.

The patch itself looks good to me.

Reviewed-by: Simon Horman horms@kernel.org

---

Hello everyone,

There is a possible NULL pointer dereference in the prueth_probe() function of the icssg_prueth driver. I discovered this while testing a platform with one PRUETH MAC enabled out of the two available.

These are the requirements to reproduce the bug:

prueth_probe() is called either eth0_node or eth1_node is not NULL in emac_phy_connect: of_phy_connect() returns NULL

Then, the following leads to the NULL pointer dereference:

prueth->emac[PRUETH_MAC0]->ndev->phydev is set to NULL prueth->emac[PRUETH_MAC0]->ndev->phydev is passed to phy_attached_info() -> phy_attached_print() dereferences phydev which is NULL

This series provides a fix by checking the return code of emac_phy_connect().

Best Regards,

Romain

drivers/net/ethernet/ti/icssg/icssg_prueth.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.c b/drivers/net/ethernet/ti/icssg/icssg_prueth.c index 7c9e9518f555a..1ea3fbd5e954e 100644 --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.c +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.c @@ -1039,7 +1039,12 @@ static int prueth_probe(struct platform_device *pdev) prueth->registered_netdevs[PRUETH_MAC0] = prueth->emac[PRUETH_MAC0]->ndev;

• emac_phy_connect(prueth->emac[PRUETH_MAC0]);
  

• ret = emac_phy_connect(prueth->emac[PRUETH_MAC0]);
  

• if (ret) {
  

• 	dev_err(dev,
  

• 		"can't connect to MII0 PHY, error -%d", ret);
  

• 	goto netdev_unregister;
  

• }
  

  phy_attached_info(prueth->emac[PRUETH_MAC0]->ndev->phydev); }

@@ -1051,7 +1056,12 @@ static int prueth_probe(struct platform_device *pdev) } prueth->registered_netdevs[PRUETH_MAC1] = prueth->emac[PRUETH_MAC1]->ndev;

• emac_phy_connect(prueth->emac[PRUETH_MAC1]);
  

• ret = emac_phy_connect(prueth->emac[PRUETH_MAC1]);
  

• if (ret) {
  

• 	dev_err(dev,
  

• 		"can't connect to MII1 PHY, error %d", ret);
  

• 	goto netdev_unregister;
  

• }
  

  phy_attached_info(prueth->emac[PRUETH_MAC1]->ndev->phydev); }

---

base-commit: e4a87abf588536d1cdfb128595e6e680af5cf3ed change-id: 20240521-icssg-prueth-fix-03b03064c5ce

Best regards,

Romain Gantois romain.gantois@bootlin.com