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/input/input-compat.h | 81 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 drivers/input/input-compat.h (limited to 'drivers/input/input-compat.h') diff --git a/drivers/input/input-compat.h b/drivers/input/input-compat.h new file mode 100644 index 000000000..99c87ceb9 --- /dev/null +++ b/drivers/input/input-compat.h @@ -0,0 +1,81 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _INPUT_COMPAT_H +#define _INPUT_COMPAT_H + +/* + * 32bit compatibility wrappers for the input subsystem. + * + * Very heavily based on evdev.c - Copyright (c) 1999-2002 Vojtech Pavlik + */ + +#include +#include +#include + +#ifdef CONFIG_COMPAT + +struct input_event_compat { + compat_ulong_t sec; + compat_ulong_t usec; + __u16 type; + __u16 code; + __s32 value; +}; + +struct ff_periodic_effect_compat { + __u16 waveform; + __u16 period; + __s16 magnitude; + __s16 offset; + __u16 phase; + + struct ff_envelope envelope; + + __u32 custom_len; + compat_uptr_t custom_data; +}; + +struct ff_effect_compat { + __u16 type; + __s16 id; + __u16 direction; + struct ff_trigger trigger; + struct ff_replay replay; + + union { + struct ff_constant_effect constant; + struct ff_ramp_effect ramp; + struct ff_periodic_effect_compat periodic; + struct ff_condition_effect condition[2]; /* One for each axis */ + struct ff_rumble_effect rumble; + } u; +}; + +static inline size_t input_event_size(void) +{ + return (in_compat_syscall() && !COMPAT_USE_64BIT_TIME) ? + sizeof(struct input_event_compat) : sizeof(struct input_event); +} + +#else + +static inline size_t input_event_size(void) +{ + return sizeof(struct input_event); +} + +#endif /* CONFIG_COMPAT */ + +int input_event_from_user(const char __user *buffer, + struct input_event *event); + +int input_event_to_user(char __user *buffer, + const struct input_event *event); + +int input_ff_effect_from_user(const char __user *buffer, size_t size, + struct ff_effect *effect); + +int input_bits_to_string(char *buf, int buf_size, unsigned long bits, + bool skip_empty); + +#endif /* _INPUT_COMPAT_H */ -- cgit v1.3.1