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 --- scripts/prune-kernel | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100755 scripts/prune-kernel (limited to 'scripts/prune-kernel') diff --git a/scripts/prune-kernel b/scripts/prune-kernel new file mode 100755 index 000000000..dadfd0e47 --- /dev/null +++ b/scripts/prune-kernel @@ -0,0 +1,25 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# because I use CONFIG_LOCALVERSION_AUTO, not the same version again and +# again, /boot and /lib/modules/ eventually fill up. +# Dumb script to purge that stuff: + +for f in "$@" +do + if rpm -qf "/lib/modules/$f" >/dev/null; then + echo "keeping $f (installed from rpm)" + elif [ $(uname -r) = "$f" ]; then + echo "keeping $f (running kernel) " + else + echo "removing $f" + rm -f "/boot/initramfs-$f.img" "/boot/System.map-$f" + rm -f "/boot/vmlinuz-$f" "/boot/config-$f" + rm -rf "/lib/modules/$f" + if [ -x "$(command -v new-kernel-pkg)" ]; then + new-kernel-pkg --remove $f + elif [ -x "$(command -v kernel-install)" ]; then + kernel-install remove $f + fi + fi +done -- cgit v1.3.1