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 --- arch/arm64/tools/Makefile | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 arch/arm64/tools/Makefile (limited to 'arch/arm64/tools/Makefile') diff --git a/arch/arm64/tools/Makefile b/arch/arm64/tools/Makefile new file mode 100644 index 000000000..a94b3d9ca --- /dev/null +++ b/arch/arm64/tools/Makefile @@ -0,0 +1,34 @@ +# SPDX-License-Identifier: GPL-2.0 + +gen := arch/$(ARCH)/include/generated +kapi := $(gen)/asm + +kapisyshdr-y := cpucap-defs.h kernel-hwcap.h sysreg-defs.h + +kapi-hdrs-y := $(addprefix $(kapi)/, $(kapisyshdr-y)) + +targets += $(addprefix ../../../, $(kapi-hdrs-y)) + +PHONY += kapi + +all: $(syscall64) kapi + +kapi: $(kapi-hdrs-y) + +quiet_cmd_gen_cpucaps = GEN $@ + cmd_gen_cpucaps = mkdir -p $(dir $@); $(AWK) -f $(real-prereqs) > $@ + +quiet_cmd_gen_kernel_hwcap = GEN $@ + cmd_gen_kernel_hwcap = mkdir -p $(dir $@); /bin/sh -e $(real-prereqs) > $@ + +quiet_cmd_gen_sysreg = GEN $@ + cmd_gen_sysreg = mkdir -p $(dir $@); $(AWK) -f $(real-prereqs) > $@ + +$(kapi)/cpucap-defs.h: $(src)/gen-cpucaps.awk $(src)/cpucaps FORCE + $(call if_changed,gen_cpucaps) + +$(kapi)/kernel-hwcap.h: $(src)/gen-kernel-hwcaps.sh $(srctree)/arch/arm64/include/uapi/asm/hwcap.h FORCE + $(call if_changed,gen_kernel_hwcap) + +$(kapi)/sysreg-defs.h: $(src)/gen-sysreg.awk $(src)/sysreg FORCE + $(call if_changed,gen_sysreg) -- cgit v1.3.1