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/nxt6000.h | 36 +++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 drivers/media/dvb-frontends/nxt6000.h (limited to 'drivers/media/dvb-frontends/nxt6000.h') diff --git a/drivers/media/dvb-frontends/nxt6000.h b/drivers/media/dvb-frontends/nxt6000.h new file mode 100644 index 000000000..28d965e53 --- /dev/null +++ b/drivers/media/dvb-frontends/nxt6000.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + NxtWave Communications - NXT6000 demodulator driver + + Copyright (C) 2002-2003 Florian Schirmer + Copyright (C) 2003 Paul Andreassen + +*/ + +#ifndef NXT6000_H +#define NXT6000_H + +#include + +struct nxt6000_config +{ + /* the demodulator's i2c address */ + u8 demod_address; + + /* should clock inversion be used? */ + u8 clock_inversion:1; +}; + +#if IS_REACHABLE(CONFIG_DVB_NXT6000) +extern struct dvb_frontend* nxt6000_attach(const struct nxt6000_config* config, + struct i2c_adapter* i2c); +#else +static inline struct dvb_frontend* nxt6000_attach(const struct nxt6000_config* config, + struct i2c_adapter* i2c) +{ + printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__); + return NULL; +} +#endif // CONFIG_DVB_NXT6000 + +#endif // NXT6000_H -- cgit v1.3.1