[PATCH net] net: ethtool: pse-pd: Fix possible null-deref

From: Kory Maincent
Date: Tue Jul 09 2024 - 09:12:16 EST


Fix a possible null dereference when a PSE supports both c33 and PoDL, but
only one of the netlink attributes is specified. The c33 or PoDL PSE
capabilities are already validated in the ethnl_set_pse_validate() call.

Signed-off-by: Kory Maincent <kory.maincent@xxxxxxxxxxx>
Reported-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Closes: https://lore.kernel.org/netdev/20240705184116.13d8235a@xxxxxxxxxx/
Fixes: 4d18e3ddf427 ("net: ethtool: pse-pd: Expand pse commands with the PSE PoE interface")
---
net/ethtool/pse-pd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ethtool/pse-pd.c b/net/ethtool/pse-pd.c
index 2c981d443f27..9dc70eb50039 100644
--- a/net/ethtool/pse-pd.c
+++ b/net/ethtool/pse-pd.c
@@ -178,9 +178,9 @@ ethnl_set_pse(struct ethnl_req_info *req_info, struct genl_info *info)

phydev = dev->phydev;
/* These values are already validated by the ethnl_pse_set_policy */
- if (pse_has_podl(phydev->psec))
+ if (tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL])
config.podl_admin_control = nla_get_u32(tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL]);
- if (pse_has_c33(phydev->psec))
+ if (tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL])
config.c33_admin_control = nla_get_u32(tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL]);

/* Return errno directly - PSE has no notification */
--
2.34.1