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/pic32/common/Makefile | 6 +++++ arch/mips/pic32/common/irq.c | 13 ++++++++++ arch/mips/pic32/common/reset.c | 55 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 74 insertions(+) create mode 100644 arch/mips/pic32/common/Makefile create mode 100644 arch/mips/pic32/common/irq.c create mode 100644 arch/mips/pic32/common/reset.c (limited to 'arch/mips/pic32/common') diff --git a/arch/mips/pic32/common/Makefile b/arch/mips/pic32/common/Makefile new file mode 100644 index 000000000..a60750ab7 --- /dev/null +++ b/arch/mips/pic32/common/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Joshua Henderson, +# Copyright (C) 2015 Microchip Technology, Inc. All rights reserved. +# +obj-y = reset.o irq.o diff --git a/arch/mips/pic32/common/irq.c b/arch/mips/pic32/common/irq.c new file mode 100644 index 000000000..fb00b797b --- /dev/null +++ b/arch/mips/pic32/common/irq.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Joshua Henderson + * Copyright (C) 2015 Microchip Technology Inc. All rights reserved. + */ +#include +#include +#include + +void __init arch_init_irq(void) +{ + irqchip_init(); +} diff --git a/arch/mips/pic32/common/reset.c b/arch/mips/pic32/common/reset.c new file mode 100644 index 000000000..230db4bad --- /dev/null +++ b/arch/mips/pic32/common/reset.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Joshua Henderson + * Copyright (C) 2015 Microchip Technology Inc. All rights reserved. + */ +#include +#include +#include +#include +#include + +#define PIC32_RSWRST 0x10 + +static void pic32_halt(void) +{ + while (1) { + __asm__(".set push;\n" + ".set arch=r4000;\n" + "wait;\n" + ".set pop;\n" + ); + } +} + +static void pic32_machine_restart(char *command) +{ + void __iomem *reg = + ioremap(PIC32_BASE_RESET + PIC32_RSWRST, sizeof(u32)); + + pic32_syskey_unlock(); + + /* magic write/read */ + __raw_writel(1, reg); + (void)__raw_readl(reg); + + pic32_halt(); +} + +static void pic32_machine_halt(void) +{ + local_irq_disable(); + + pic32_halt(); +} + +static int __init mips_reboot_setup(void) +{ + _machine_restart = pic32_machine_restart; + _machine_halt = pic32_machine_halt; + pm_power_off = pic32_machine_halt; + + return 0; +} + +arch_initcall(mips_reboot_setup); -- cgit v1.3.1