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/media/dvb-frontends/isl6421.h | 38 +++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 drivers/media/dvb-frontends/isl6421.h (limited to 'drivers/media/dvb-frontends/isl6421.h') diff --git a/drivers/media/dvb-frontends/isl6421.h b/drivers/media/dvb-frontends/isl6421.h new file mode 100644 index 000000000..e59487784 --- /dev/null +++ b/drivers/media/dvb-frontends/isl6421.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * isl6421.h - driver for lnb supply and control ic ISL6421 + * + * Copyright (C) 2006 Andrew de Quincey + * Copyright (C) 2006 Oliver Endriss + * + * the project's page is at https://linuxtv.org + */ + +#ifndef _ISL6421_H +#define _ISL6421_H + +#include + +/* system register bits */ +#define ISL6421_OLF1 0x01 +#define ISL6421_EN1 0x02 +#define ISL6421_VSEL1 0x04 +#define ISL6421_LLC1 0x08 +#define ISL6421_ENT1 0x10 +#define ISL6421_ISEL1 0x20 +#define ISL6421_DCL 0x40 + +#if IS_REACHABLE(CONFIG_DVB_ISL6421) +/* override_set and override_clear control which system register bits (above) to always set & clear */ +extern struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr, + u8 override_set, u8 override_clear, bool override_tone); +#else +static inline struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, u8 i2c_addr, + u8 override_set, u8 override_clear, bool override_tone) +{ + printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__); + return NULL; +} +#endif // CONFIG_DVB_ISL6421 + +#endif -- cgit v1.3.1