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/gen-kernel-hwcaps.sh | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 arch/arm64/tools/gen-kernel-hwcaps.sh (limited to 'arch/arm64/tools/gen-kernel-hwcaps.sh') diff --git a/arch/arm64/tools/gen-kernel-hwcaps.sh b/arch/arm64/tools/gen-kernel-hwcaps.sh new file mode 100644 index 000000000..e7cdcf428 --- /dev/null +++ b/arch/arm64/tools/gen-kernel-hwcaps.sh @@ -0,0 +1,23 @@ +#!/bin/sh -e +# SPDX-License-Identifier: GPL-2.0 +# +# gen-kernel-hwcap.sh - Generate kernel internal hwcap.h definitions +# +# Copyright 2026 Arm, Ltd. + +if [ "$1" = "" ]; then + echo "$0: no filename specified" + exit 1 +fi + +echo "#ifndef __ASM_KERNEL_HWCAPS_H" +echo "#define __ASM_KERNEL_HWCAPS_H" +echo "" +echo "/* Generated file - do not edit */" +echo "" + +grep -E '^#define HWCAP[0-9]*_[A-Z0-9_]+' $1 | \ + sed 's/.*HWCAP\([0-9]*\)_\([A-Z0-9_]\+\).*/#define KERNEL_HWCAP_\2\t__khwcap\1_feature(\2)/' + +echo "" +echo "#endif /* __ASM_KERNEL_HWCAPS_H */" -- cgit v1.3.1