From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- drivers/hwmon/peci/common.h | 55 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 drivers/hwmon/peci/common.h (limited to 'drivers/hwmon/peci/common.h') diff --git a/drivers/hwmon/peci/common.h b/drivers/hwmon/peci/common.h new file mode 100644 index 000000000..5eae9681e --- /dev/null +++ b/drivers/hwmon/peci/common.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (c) 2021 Intel Corporation */ + +#include + +#ifndef __PECI_HWMON_COMMON_H +#define __PECI_HWMON_COMMON_H + +#define PECI_HWMON_UPDATE_INTERVAL HZ + +/** + * struct peci_sensor_state - PECI state information + * @valid: flag to indicate the sensor value is valid + * @last_updated: time of the last update in jiffies + */ +struct peci_sensor_state { + bool valid; + unsigned long last_updated; +}; + +/** + * struct peci_sensor_data - PECI sensor information + * @value: sensor value in milli units + * @state: sensor update state + */ + +struct peci_sensor_data { + s32 value; + struct peci_sensor_state state; +}; + +/** + * peci_sensor_need_update() - check whether sensor update is needed or not + * @state: pointer to sensor state struct + * + * Return: true if update is needed, false if not. + */ + +static inline bool peci_sensor_need_update(struct peci_sensor_state *state) +{ + return !state->valid || + time_after(jiffies, state->last_updated + PECI_HWMON_UPDATE_INTERVAL); +} + +/** + * peci_sensor_mark_updated() - mark the sensor is updated + * @state: pointer to sensor state struct + */ +static inline void peci_sensor_mark_updated(struct peci_sensor_state *state) +{ + state->valid = true; + state->last_updated = jiffies; +} + +#endif /* __PECI_HWMON_COMMON_H */ -- cgit v1.3.1