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/mips/generic/board-serval.its.S | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 arch/mips/generic/board-serval.its.S (limited to 'arch/mips/generic/board-serval.its.S') diff --git a/arch/mips/generic/board-serval.its.S b/arch/mips/generic/board-serval.its.S new file mode 100644 index 000000000..dde833efe --- /dev/null +++ b/arch/mips/generic/board-serval.its.S @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */ +/ { + images { + fdt-serval_pcb105 { + description = "MSCC Serval PCB105 Device Tree"; + data = /incbin/("boot/dts/mscc/serval_pcb105.dtb"); + type = "flat_dt"; + arch = "mips"; + compression = "none"; + hash { + algo = "sha1"; + }; + }; + }; + + configurations { + pcb105 { + description = "Serval Linux kernel"; + kernel = "kernel"; + fdt = "fdt-serval_pcb105"; + ramdisk = "ramdisk"; + }; + }; +}; -- cgit v1.3.1