diff options
| author | Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> | 2023-05-03 16:38:50 -0700 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2023-05-04 20:30:18 +0200 |
| commit | b5d68f84f4c62c78bc3d004911d80da5aa22df8b (patch) | |
| tree | f170a4b0c7125b071620da067ac9f0a8a98a6950 /drivers | |
| parent | 667de5c68440732373f571f7eac4ff44b1b93ee7 (diff) | |
thermal: intel: powerclamp: Fix NULL pointer access issue
If cur_state for the powerclamp cooling device is set to the default
minimum state of 0, without setting first to cur_state > 0, this results
in NULL pointer access.
This NULL pointer access happens in the powercap core idle-inject
function idle_inject_set_duration() as there is no NULL check for
idle_inject_device pointer. This pointer must be allocated by calling
idle_inject_register() or idle_inject_register_full().
In the function powerclamp_set_cur_state(), idle_inject_device pointer
is allocated only when the cur_state > 0. But setting 0 without changing
to any other state, idle_inject_set_duration() will be called with a
NULL idle_inject_device pointer.
To address this, just return from powerclamp_set_cur_state() if the
current cooling device state is the same as the last one. Since the
power-up default cooling device state is 0, changing the state to 0
again here will return without calling idle_inject_set_duration().
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Fixes: 8526eb7fc75a ("thermal: intel: powerclamp: Use powercap idle-inject feature")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=217386
Tested-by: Risto A. Paju <teknohog@iki.fi>
Cc: 6.3+ <stable@kernel.org> # 6.3+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/thermal/intel/intel_powerclamp.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/thermal/intel/intel_powerclamp.c b/drivers/thermal/intel/intel_powerclamp.c index 91fc7e239497..36243a3972fd 100644 --- a/drivers/thermal/intel/intel_powerclamp.c +++ b/drivers/thermal/intel/intel_powerclamp.c @@ -703,6 +703,10 @@ static int powerclamp_set_cur_state(struct thermal_cooling_device *cdev, new_target_ratio = clamp(new_target_ratio, 0UL, (unsigned long) (max_idle - 1)); + + if (powerclamp_data.target_ratio == new_target_ratio) + goto exit_set; + if (!powerclamp_data.target_ratio && new_target_ratio > 0) { pr_info("Start idle injection to reduce power\n"); powerclamp_data.target_ratio = new_target_ratio; |