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/powerpc/boot/ep8248e.c | 52 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 arch/powerpc/boot/ep8248e.c (limited to 'arch/powerpc/boot/ep8248e.c') diff --git a/arch/powerpc/boot/ep8248e.c b/arch/powerpc/boot/ep8248e.c new file mode 100644 index 000000000..2ab9e0d8c --- /dev/null +++ b/arch/powerpc/boot/ep8248e.c @@ -0,0 +1,52 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Embedded Planet EP8248E with PlanetCore firmware + * + * Author: Scott Wood + * + * Copyright (c) 2007 Freescale Semiconductor, Inc. + */ + +#include "ops.h" +#include "stdio.h" +#include "planetcore.h" +#include "pq2.h" + +static char *table; +static u64 mem_size; + +#include + +static void platform_fixups(void) +{ + u64 val; + + dt_fixup_memory(0, mem_size); + planetcore_set_mac_addrs(table); + + if (!planetcore_get_decimal(table, PLANETCORE_KEY_CRYSTAL_HZ, &val)) { + printf("No PlanetCore crystal frequency key.\r\n"); + return; + } + + pq2_fixup_clocks(val); +} + +void platform_init(unsigned long r3, unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7) +{ + table = (char *)r3; + planetcore_prepare_table(table); + + if (!planetcore_get_decimal(table, PLANETCORE_KEY_MB_RAM, &mem_size)) + return; + + mem_size *= 1024 * 1024; + simple_alloc_init(_end, mem_size - (unsigned long)_end, 32, 64); + + fdt_init(_dtb_start); + + planetcore_set_stdout_path(table); + serial_console_init(); + platform_ops.fixups = platform_fixups; +} -- cgit v1.3.1