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/arm/nwfpe/Makefile | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 arch/arm/nwfpe/Makefile (limited to 'arch/arm/nwfpe/Makefile') diff --git a/arch/arm/nwfpe/Makefile b/arch/arm/nwfpe/Makefile new file mode 100644 index 000000000..2aec85ab1 --- /dev/null +++ b/arch/arm/nwfpe/Makefile @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (C) 1998, 1999, 2001 Philip Blundell +# + +obj-$(CONFIG_FPE_NWFPE) += nwfpe.o + +nwfpe-y += fpa11.o fpa11_cpdo.o fpa11_cpdt.o \ + fpa11_cprt.o fpmodule.o fpopcode.o \ + softfloat.o single_cpdo.o double_cpdo.o \ + entry.o + +nwfpe-$(CONFIG_FPE_NWFPE_XP) += extended_cpdo.o + +# Try really hard to avoid generating calls to __aeabi_uldivmod() from +# float64_rem() due to loop elision. +ifdef CONFIG_CC_IS_CLANG +CFLAGS_softfloat.o += -mllvm -replexitval=never +endif -- cgit v1.3.1