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/iommu/irq_remapping.h | 59 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 drivers/iommu/irq_remapping.h (limited to 'drivers/iommu/irq_remapping.h') diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h new file mode 100644 index 000000000..0d6f140b5 --- /dev/null +++ b/drivers/iommu/irq_remapping.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2012 Advanced Micro Devices, Inc. + * Author: Joerg Roedel + * + * This header file contains stuff that is shared between different interrupt + * remapping drivers but with no need to be visible outside of the IOMMU layer. + */ + +#ifndef __IRQ_REMAPPING_H +#define __IRQ_REMAPPING_H + +#ifdef CONFIG_IRQ_REMAP + +struct irq_data; +struct msi_msg; +struct irq_domain; +struct irq_alloc_info; + +extern int irq_remap_broken; +extern int disable_sourceid_checking; +extern int no_x2apic_optout; +extern int irq_remapping_enabled; + +extern int disable_irq_post; + +struct irq_remap_ops { + /* The supported capabilities */ + int capability; + + /* Initializes hardware and makes it ready for remapping interrupts */ + int (*prepare)(void); + + /* Enables the remapping hardware */ + int (*enable)(void); + + /* Disables the remapping hardware */ + void (*disable)(void); + + /* Reenables the remapping hardware */ + int (*reenable)(int); + + /* Enable fault handling */ + int (*enable_faulting)(unsigned int); +}; + +extern struct irq_remap_ops intel_irq_remap_ops; +extern struct irq_remap_ops amd_iommu_irq_ops; +extern struct irq_remap_ops hyperv_irq_remap_ops; + +#else /* CONFIG_IRQ_REMAP */ + +#define irq_remapping_enabled 0 +#define irq_remap_broken 0 +#define disable_irq_post 1 + +#endif /* CONFIG_IRQ_REMAP */ + +#endif /* __IRQ_REMAPPING_H */ -- cgit v1.3.1