Re: [PATCH] ACPI: scan: Fix a memory leak in an error handling path

[Edmundo Carmona Antoranz <eantoranz@xxxxxxxxx>]

On Sat, May 8, 2021 at 1:23 AM Christophe JAILLET
<christophe.jaillet@xxxxxxxxxx> wrote:
>
> If 'acpi_device_set_name()' fails, we must free
> 'acpi_device_bus_id->bus_id' or there is a (potential) memory leak.

This is a question about the style used in kernel. This function
(acpi_device_add) initializes acpi_device_bus_id and it could also
initialize acpi_device_bus_id->bus_id and any of those might fail. And
they will have to be freed if they are initialized and so on. I see
that there are kfrees used for them in different places before using a
goto err_unlock; I wonder if it is accepted practice to avoid doing
these kfrees and have them in a single place instead, something like:

err_onlock:
    if (acpi_device_bus_id) {
        if (acpi_device_bus_id->bus_id)
            kfree(acpi_device_bus_id->bus_id);
        kfree(acpi_device_bus_id);
    }
    mutex_unlock(&acpi_device_lock);
.
.
.

Thanks in advance.