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 --- tools/firmware/Makefile | 13 +++++++++++++ 1 file changed, 13 insertions(+) create mode 100644 tools/firmware/Makefile (limited to 'tools/firmware/Makefile') diff --git a/tools/firmware/Makefile b/tools/firmware/Makefile new file mode 100644 index 000000000..cfb297e6e --- /dev/null +++ b/tools/firmware/Makefile @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0 +# Makefile for firmware tools + +CFLAGS = -Wall -Wextra -g + +all: ihex2fw +%: %.c + $(CC) $(CFLAGS) -o $@ $^ + +clean: + $(RM) ihex2fw + +.PHONY: all clean -- cgit v1.3.1