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 --- drivers/clk/st/clkgen.h | 51 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 drivers/clk/st/clkgen.h (limited to 'drivers/clk/st/clkgen.h') diff --git a/drivers/clk/st/clkgen.h b/drivers/clk/st/clkgen.h new file mode 100644 index 000000000..44302fc7c --- /dev/null +++ b/drivers/clk/st/clkgen.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/************************************************************************ +File : Clock H/w specific Information + +Author: Pankaj Dev + +Copyright (C) 2014 STMicroelectronics +************************************************************************/ + +#ifndef __CLKGEN_INFO_H +#define __CLKGEN_INFO_H + +extern spinlock_t clkgen_a9_lock; + +struct clkgen_field { + unsigned int offset; + unsigned int mask; + unsigned int shift; +}; + +static inline unsigned long clkgen_read(void __iomem *base, + struct clkgen_field *field) +{ + return (readl(base + field->offset) >> field->shift) & field->mask; +} + + +static inline void clkgen_write(void __iomem *base, struct clkgen_field *field, + unsigned long val) +{ + writel((readl(base + field->offset) & + ~(field->mask << field->shift)) | (val << field->shift), + base + field->offset); + + return; +} + +#define CLKGEN_FIELD(_offset, _mask, _shift) { \ + .offset = _offset, \ + .mask = _mask, \ + .shift = _shift, \ + } + +#define CLKGEN_READ(pll, field) clkgen_read(pll->regs_base, \ + &pll->data->field) + +#define CLKGEN_WRITE(pll, field, val) clkgen_write(pll->regs_base, \ + &pll->data->field, val) + +#endif /*__CLKGEN_INFO_H*/ + -- cgit v1.3.1