realtek: mdio: harden mdio probing

Do better error checks during bus probing. Give meaningful return codes
in case of invalid DTS data (EINVAL instead of ENODEV). Decrease node
reference in case of errors.

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://github.com/openwrt/openwrt/pull/21968
Signed-off-by: Robert Marko <robimarko@gmail.com>

diff --git a/target/linux/realtek/files-6.12/drivers/net/mdio/mdio-realtek-otto.c b/target/linux/realtek/files-6.12/drivers/net/mdio/mdio-realtek-otto.c
index bb61b9d48c6dcef3774f3d4696889367ac2780a6..628de4790a8f6f801184380345d189dff2b16a23 100644 (file)
--- a/target/linux/realtek/files-6.12/drivers/net/mdio/mdio-realtek-otto.c
+++ b/target/linux/realtek/files-6.12/drivers/net/mdio/mdio-realtek-otto.c
@@ -913,18 +913,20 @@ static int rtmdio_probe(struct platform_device *pdev)
                if (of_property_read_u32(dn, "reg", &addr))
                        continue;
 
-               if (addr >= ctrl->cfg->cpu_port) {
-                       pr_err("%s: illegal port number %d\n", __func__, addr);
-                       return -ENODEV;
+               if (addr < 0 || addr >= ctrl->cfg->cpu_port) {
+                       dev_err(dev, "illegal port number %d\n", addr);
+                       of_node_put(dn);
+                       return -EINVAL;
                }
 
                of_property_read_u32(dn->parent, "reg", &ctrl->smi_bus[addr]);
                if (of_property_read_u32(dn, "realtek,smi-address", &ctrl->smi_addr[addr]))
                        ctrl->smi_addr[addr] = addr;
                
-               if (ctrl->smi_bus[addr] >= RTMDIO_MAX_SMI_BUS) {
-                       pr_err("%s: illegal SMI bus number %d\n", __func__, ctrl->smi_bus[addr]);
-                       return -ENODEV;
+               if (ctrl->smi_bus[addr] < 0 || ctrl->smi_bus[addr] >= RTMDIO_MAX_SMI_BUS) {
+                       dev_err(dev, "illegal SMI bus number %d\n", ctrl->smi_bus[addr]);
+                       of_node_put(dn);
+                       return -EINVAL;
                }
 
                if (of_device_is_compatible(dn, "ethernet-phy-ieee802.3-c45"))