lkml.org 
[lkml]   [2023]   [Dec]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [PATCH v1] thermal: core: Fix NULL pointer dereference in zone registration error path
    From


    On 12/14/23 10:52, Rafael J. Wysocki wrote:
    > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    >
    > If device_register() in thermal_zone_device_register_with_trips()
    > returns an error, the tz variable is set to NULL and subsequently
    > dereferenced in kfree(tz->tzp).
    >
    > Commit adc8749b150c ("thermal/drivers/core: Use put_device() if
    > device_register() fails") added the tz = NULL assignment in question to
    > avoid a possible double-free after dropping the reference to the zone
    > device. However, after commit 4649620d9404 ("thermal: core: Make
    > thermal_zone_device_unregister() return after freeing the zone"), that
    > assignment has become redundant, because dropping the reference to the
    > zone device does not cause the zone object to be freed any more.
    >
    > Drop it to address the NULL pointer dereference.
    >
    > Fixes: 3d439b1a2ad3 ("thermal/core: Alloc-copy-free the thermal zone parameters structure")
    > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    > ---
    > drivers/thermal/thermal_core.c | 1 -
    > 1 file changed, 1 deletion(-)
    >
    > Index: linux-pm/drivers/thermal/thermal_core.c
    > ===================================================================
    > --- linux-pm.orig/drivers/thermal/thermal_core.c
    > +++ linux-pm/drivers/thermal/thermal_core.c
    > @@ -1394,7 +1394,6 @@ unregister:
    > device_del(&tz->device);
    > release_device:
    > put_device(&tz->device);
    > - tz = NULL;
    > remove_id:
    > ida_free(&thermal_tz_ida, id);
    > free_tzp:
    >
    >
    >

    Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>

    \
     
     \ /
      Last update: 2023-12-15 16:31    [W:2.261 / U:1.640 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site