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/module.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 include/asm-generic/module.h (limited to 'include/asm-generic/module.h') diff --git a/include/asm-generic/module.h b/include/asm-generic/module.h new file mode 100644 index 000000000..a8622501b --- /dev/null +++ b/include/asm-generic/module.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_GENERIC_MODULE_H +#define __ASM_GENERIC_MODULE_H + +/* + * Many architectures just need a simple module + * loader without arch specific data. + */ +#ifndef CONFIG_HAVE_MOD_ARCH_SPECIFIC +struct mod_arch_specific +{ +}; +#endif + +#ifdef CONFIG_64BIT +#define Elf_Shdr Elf64_Shdr +#define Elf_Phdr Elf64_Phdr +#define Elf_Sym Elf64_Sym +#define Elf_Dyn Elf64_Dyn +#define Elf_Ehdr Elf64_Ehdr +#define Elf_Addr Elf64_Addr +#define Elf_Rel Elf64_Rel +#define Elf_Rela Elf64_Rela +#define ELF_R_TYPE(X) ELF64_R_TYPE(X) +#define ELF_R_SYM(X) ELF64_R_SYM(X) + +#else /* CONFIG_64BIT */ + +#define Elf_Shdr Elf32_Shdr +#define Elf_Phdr Elf32_Phdr +#define Elf_Sym Elf32_Sym +#define Elf_Dyn Elf32_Dyn +#define Elf_Ehdr Elf32_Ehdr +#define Elf_Addr Elf32_Addr +#define Elf_Rel Elf32_Rel +#define Elf_Rela Elf32_Rela +#define ELF_R_TYPE(X) ELF32_R_TYPE(X) +#define ELF_R_SYM(X) ELF32_R_SYM(X) +#endif + +#endif /* __ASM_GENERIC_MODULE_H */ -- cgit v1.3.1