[PATCH] ARM: amba: Fix leak of driver_override attribute value

[PATCH] ARM: amba: Fix leak of driver_override attribute value

[Trent Piepho]

If driver_override was set when a device was released the string would
not be kfree'ed in amba_device_release and thus leaked when the amba
device was freed.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Todd Kjos <tkjos@google.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
---
 drivers/amba/bus.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 41b706403ef7..ff3cb96526bc 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -347,6 +347,7 @@ static void amba_device_release(struct device *dev)
 
 	if (d->res.parent)
 		release_resource(&d->res);
+	kfree(d->driver_override);
 	kfree(d);
 }
 
-- 
2.14.4

Re: [PATCH] ARM: amba: Fix leak of driver_override attribute value

[Geert Uytterhoeven]

On Thu, Sep 20, 2018 at 1:48 AM Trent Piepho <tpiepho@impinj.com> wrote:
> If driver_override was set when a device was released the string would
> not be kfree'ed in amba_device_release and thus leaked when the amba
> device was freed.
>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Todd Kjos <tkjos@google.com>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Trent Piepho <tpiepho@impinj.com>

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device
binding path 'driver_override'")
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] ARM: amba: Fix leak of driver_override attribute value

[Greg KH]

On Thu, Sep 20, 2018 at 08:48:36AM +0200, Geert Uytterhoeven wrote:
> On Thu, Sep 20, 2018 at 1:48 AM Trent Piepho <tpiepho@impinj.com> wrote:
> > If driver_override was set when a device was released the string would
> > not be kfree'ed in amba_device_release and thus leaked when the amba
> > device was freed.
> >
> > Cc: Russell King <linux@armlinux.org.uk>
> > Cc: Todd Kjos <tkjos@google.com>
> > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Signed-off-by: Trent Piepho <tpiepho@impinj.com>
> 
> Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device
> binding path 'driver_override'")

Then it should also have a cc: stable, right?

thanks,

greg k-h

Re: [PATCH] ARM: amba: Fix leak of driver_override attribute value

[Geert Uytterhoeven]

Hi Greg,

On Thu, Sep 20, 2018 at 9:09 AM Greg KH <gregkh@linuxfoundation.org> wrote:
> On Thu, Sep 20, 2018 at 08:48:36AM +0200, Geert Uytterhoeven wrote:
> > On Thu, Sep 20, 2018 at 1:48 AM Trent Piepho <tpiepho@impinj.com> wrote:
> > > If driver_override was set when a device was released the string would
> > > not be kfree'ed in amba_device_release and thus leaked when the amba
> > > device was freed.
> > >
> > > Cc: Russell King <linux@armlinux.org.uk>
> > > Cc: Todd Kjos <tkjos@google.com>
> > > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > Signed-off-by: Trent Piepho <tpiepho@impinj.com>
> >
> > Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device
> > binding path 'driver_override'")
>
> Then it should also have a cc: stable, right?

Perhaps. I usually leave that up to the maintainer, else git send-email sends
it to stable immediately.

The modern backporting AI will consider it anyway, due to the subject, and
the Fixes tag, right?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] ARM: amba: Fix leak of driver_override attribute value

[Greg KH]

On Thu, Sep 20, 2018 at 09:16:36AM +0200, Geert Uytterhoeven wrote:
> Hi Greg,
> 
> On Thu, Sep 20, 2018 at 9:09 AM Greg KH <gregkh@linuxfoundation.org> wrote:
> > On Thu, Sep 20, 2018 at 08:48:36AM +0200, Geert Uytterhoeven wrote:
> > > On Thu, Sep 20, 2018 at 1:48 AM Trent Piepho <tpiepho@impinj.com> wrote:
> > > > If driver_override was set when a device was released the string would
> > > > not be kfree'ed in amba_device_release and thus leaked when the amba
> > > > device was freed.
> > > >
> > > > Cc: Russell King <linux@armlinux.org.uk>
> > > > Cc: Todd Kjos <tkjos@google.com>
> > > > Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> > > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > > Signed-off-by: Trent Piepho <tpiepho@impinj.com>
> > >
> > > Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > > Fixes: 3cf385713460eb2b ("ARM: 8256/1: driver coamba: add device
> > > binding path 'driver_override'")
> >
> > Then it should also have a cc: stable, right?
> 
> Perhaps. I usually leave that up to the maintainer, else git send-email sends
> it to stable immediately.

That's fine, no one ever complains about that.  In fact it is _good_ to
have that happen, as it gives us stable people a "heads up" that
something is coming to resolve a reported problems.

> The modern backporting AI will consider it anyway, due to the subject, and
> the Fixes tag, right?

Don't count on the "AI" to pick things up if you _know_ it resolves a
problem, like you have said here.

So please, just add it when you know it needs to be backported,
otherwise it might never get backported.

thanks,

greg k-h