Re: [PATCH] thermal: int340x: fix memory leak in int3400_notify()

[srinivas pandruvada <srinivas.pandruvada@linux.intel.com>]

On Tue, 2022-02-22 at 13:34 +0100, Rafael J. Wysocki wrote:
> Please resend this with a CC to linux-pm@vger.kernel.org.  Thanks!
> 
> On Tue, Feb 22, 2022 at 3:13 AM Chuansheng Liu
> <chuansheng.liu@intel.com> wrote:
> > 
> > It is easy to hit the below memory leaks in my TigerLake platform:
> > 
> > --
> > unreferenced object 0xffff927c8b91dbc0 (size 32):
> >   comm "kworker/0:2", pid 112, jiffies 4294893323 (age 83.604s)
> >   hex dump (first 32 bytes):
> >     4e 41 4d 45 3d 49 4e 54 33 34 30 30 20 54 68 65  NAME=INT3400
> > The
> >     72 6d 61 6c 00 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 
> > rmal.kkkkkkkkkk.
> >   backtrace:
> >     [<ffffffff9c502c3e>] __kmalloc_track_caller+0x2fe/0x4a0
> >     [<ffffffff9c7b7c15>] kvasprintf+0x65/0xd0
> >     [<ffffffff9c7b7d6e>] kasprintf+0x4e/0x70
> >     [<ffffffffc04cb662>] int3400_notify+0x82/0x120
> > [int3400_thermal]
> >     [<ffffffff9c8b7358>] acpi_ev_notify_dispatch+0x54/0x71
> >     [<ffffffff9c88f1a7>] acpi_os_execute_deferred+0x17/0x30
> >     [<ffffffff9c2c2c0a>] process_one_work+0x21a/0x3f0
> >     [<ffffffff9c2c2e2a>] worker_thread+0x4a/0x3b0
> >     [<ffffffff9c2cb4dd>] kthread+0xfd/0x130
> >     [<ffffffff9c201c1f>] ret_from_fork+0x1f/0x30
> > ---
> > 
> > Fix it by calling kfree() accordingly.
> > 
> > Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Please cc to stable

> > ---
> >  drivers/thermal/intel/int340x_thermal/int3400_thermal.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git
> > a/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
> > b/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
> > index 72acb1f61849..4f478812cb51 100644
> > --- a/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
> > +++ b/drivers/thermal/intel/int340x_thermal/int3400_thermal.c
> > @@ -404,6 +404,10 @@ static void int3400_notify(acpi_handle handle,
> >         thermal_prop[3] = kasprintf(GFP_KERNEL, "EVENT=%d",
> > therm_event);
> >         thermal_prop[4] = NULL;
> >         kobject_uevent_env(&priv->thermal->device.kobj,
> > KOBJ_CHANGE, thermal_prop);
> > +       kfree(thermal_prop[0]);
> > +       kfree(thermal_prop[1]);
> > +       kfree(thermal_prop[2]);
> > +       kfree(thermal_prop[3]);
> >  }
> > 
> >  static int int3400_thermal_get_temp(struct thermal_zone_device
> > *thermal,
> > --
> > 2.25.0.rc2
> >