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/arc/boot/Makefile | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 arch/arc/boot/Makefile (limited to 'arch/arc/boot/Makefile') diff --git a/arch/arc/boot/Makefile b/arch/arc/boot/Makefile new file mode 100644 index 000000000..5a8550124 --- /dev/null +++ b/arch/arc/boot/Makefile @@ -0,0 +1,38 @@ +# SPDX-License-Identifier: GPL-2.0 + +# uImage build relies on mkimage being available on your host for ARC target +# You will need to build u-boot for ARC, rename mkimage to arc-elf32-mkimage +# and make sure it's reachable from your PATH + +OBJCOPYFLAGS= -O binary -R .note -R .note.gnu.build-id -R .comment -S + +LINUX_START_TEXT = $$($(READELF) -h vmlinux | \ + grep "Entry point address" | grep -o 0x.*) + +UIMAGE_LOADADDR = $(CONFIG_LINUX_LINK_BASE) +UIMAGE_ENTRYADDR = $(LINUX_START_TEXT) + +targets += vmlinux.bin +targets += vmlinux.bin.gz +targets += vmlinux.bin.lzma +targets += uImage.bin +targets += uImage.gz +targets += uImage.lzma + +$(obj)/vmlinux.bin: vmlinux FORCE + $(call if_changed,objcopy) + +$(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE + $(call if_changed,gzip) + +$(obj)/vmlinux.bin.lzma: $(obj)/vmlinux.bin FORCE + $(call if_changed,lzma) + +$(obj)/uImage.bin: $(obj)/vmlinux.bin FORCE + $(call if_changed,uimage,none) + +$(obj)/uImage.gz: $(obj)/vmlinux.bin.gz FORCE + $(call if_changed,uimage,gzip) + +$(obj)/uImage.lzma: $(obj)/vmlinux.bin.lzma FORCE + $(call if_changed,uimage,lzma) -- cgit v1.3.1