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/tools/Makefile | 57 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 arch/arm/tools/Makefile (limited to 'arch/arm/tools/Makefile') diff --git a/arch/arm/tools/Makefile b/arch/arm/tools/Makefile new file mode 100644 index 000000000..28b6da8ac --- /dev/null +++ b/arch/arm/tools/Makefile @@ -0,0 +1,57 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# linux/arch/arm/tools/Makefile +# +# Copyright (C) 2001 Russell King +# + +gen := arch/$(ARCH)/include/generated +kapi := $(gen)/asm +uapi := $(gen)/uapi/asm +syshdr := $(srctree)/scripts/syscallhdr.sh +sysnr := $(src)/syscallnr.sh +systbl := $(srctree)/scripts/syscalltbl.sh +syscall := $(src)/syscall.tbl + +gen-y := $(gen)/calls-oabi.S +gen-y += $(gen)/calls-eabi.S +kapi-hdrs-y := $(kapi)/unistd-nr.h +kapi-hdrs-y += $(kapi)/mach-types.h +uapi-hdrs-y += $(uapi)/unistd-oabi.h +uapi-hdrs-y += $(uapi)/unistd-eabi.h + +targets += $(addprefix ../../../,$(gen-y) $(kapi-hdrs-y) $(uapi-hdrs-y)) + +PHONY += kapi uapi + +kapi: $(kapi-hdrs-y) $(gen-y) + +uapi: $(uapi-hdrs-y) + +# Create output directory if not already present +$(shell mkdir -p $(kapi) $(uapi)) + +quiet_cmd_gen_mach = GEN $@ + cmd_gen_mach = $(AWK) -f $(real-prereqs) > $@ + +$(kapi)/mach-types.h: $(src)/gen-mach-types $(src)/mach-types FORCE + $(call if_changed,gen_mach) + +quiet_cmd_syshdr = SYSHDR $@ + cmd_syshdr = $(CONFIG_SHELL) $(syshdr) --abis common,$* \ + --offset __NR_SYSCALL_BASE $< $@ + +quiet_cmd_systbl = SYSTBL $@ + cmd_systbl = $(CONFIG_SHELL) $(systbl) --abis common,$* $< $@ + +quiet_cmd_sysnr = SYSNR $@ + cmd_sysnr = $(CONFIG_SHELL) $(sysnr) $< $@ + +$(uapi)/unistd-%.h: $(syscall) $(syshdr) FORCE + $(call if_changed,syshdr) + +$(kapi)/unistd-nr.h: $(syscall) $(sysnr) FORCE + $(call if_changed,sysnr) + +$(gen)/calls-%.S: $(syscall) $(systbl) FORCE + $(call if_changed,systbl) -- cgit v1.3.1