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/asm-generic/msi.h | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100644 include/asm-generic/msi.h (limited to 'include/asm-generic/msi.h') diff --git a/include/asm-generic/msi.h b/include/asm-generic/msi.h new file mode 100644 index 000000000..92cca4b23 --- /dev/null +++ b/include/asm-generic/msi.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_MSI_H +#define __ASM_GENERIC_MSI_H + +#include + +#ifdef CONFIG_GENERIC_MSI_IRQ + +#ifndef NUM_MSI_ALLOC_SCRATCHPAD_REGS +# define NUM_MSI_ALLOC_SCRATCHPAD_REGS 2 +#endif + +struct msi_desc; + +/** + * struct msi_alloc_info - Default structure for MSI interrupt allocation. + * @desc: Pointer to msi descriptor + * @hwirq: Associated hw interrupt number in the domain + * @scratchpad: Storage for implementation specific scratch data + * + * Architectures can provide their own implementation by not including + * asm-generic/msi.h into their arch specific header file. + */ +typedef struct msi_alloc_info { + struct msi_desc *desc; + irq_hw_number_t hwirq; + unsigned long flags; + union { + unsigned long ul; + void *ptr; + } scratchpad[NUM_MSI_ALLOC_SCRATCHPAD_REGS]; +} msi_alloc_info_t; + +/* Device generating MSIs is proxying for another device */ +#define MSI_ALLOC_FLAGS_PROXY_DEVICE (1UL << 0) +#define MSI_ALLOC_FLAGS_FIXED_MSG_DATA (1UL << 1) + +#define GENERIC_MSI_DOMAIN_OPS 1 + +#endif /* CONFIG_GENERIC_MSI_IRQ */ + +#endif -- cgit v1.3.1