Re: [PATCH] net: sfp: fix hwmon_name leak on hwmon registration failure

[Janis Edvarts Lacis]

I have looked into the code for sfp_hwmon_remove calls to the 
best of my abilities and Andrew is right that sfp_hwmon_remove 
is called on every sfp device. 

If sfp_hwmon_probe fails in hwmon_device_register_with_info function call,
it leaves sfp->hwmon_dev as an error pointer. When sfp_check_state detects 
that SFP_F_PRESENT has changed, it sends SFP_E_REMOVE which leads to sfp_hwmon_remove  
call. In sfp_hwmon_remove sfp->hwmon_name is not freed because
!IS_ERR_OR_NULL(sfp->hwmon_dev) is false therefore the whole cleanup block is skipped.

So, as Andrew suggested, freeing sfp->hwmon_name if it is not NULL
and it is not an error pointer (hwmon_sanitize_name can return an error 
pointer) instead of freeing only when sfp->hwmon_dev is valid seems
to be the correct approach.