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 --- include/drm/drm_utils.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 include/drm/drm_utils.h (limited to 'include/drm/drm_utils.h') diff --git a/include/drm/drm_utils.h b/include/drm/drm_utils.h new file mode 100644 index 000000000..7e077484c --- /dev/null +++ b/include/drm/drm_utils.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Function prototypes for misc. drm utility functions. + * Specifically this file is for function prototypes for functions which + * may also be used outside of drm code (e.g. in fbdev drivers). + * + * Copyright (C) 2017 Hans de Goede + */ + +#ifndef __DRM_UTILS_H__ +#define __DRM_UTILS_H__ + +#include + +struct drm_edid; + +int drm_get_panel_orientation_quirk(int width, int height); + +struct drm_panel_backlight_quirk { + u16 min_brightness; + u32 brightness_mask; + bool force_pwm; +}; + +const struct drm_panel_backlight_quirk * +drm_get_panel_backlight_quirk(const struct drm_edid *edid); + +signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec); + +#endif -- cgit v1.3.1