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 --- include/media/dvb_net.h | 95 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) create mode 100644 include/media/dvb_net.h (limited to 'include/media/dvb_net.h') diff --git a/include/media/dvb_net.h b/include/media/dvb_net.h new file mode 100644 index 000000000..4a921ea96 --- /dev/null +++ b/include/media/dvb_net.h @@ -0,0 +1,95 @@ +/* + * dvb_net.h + * + * Copyright (C) 2001 Ralph Metzler for convergence integrated media GmbH + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public License + * as published by the Free Software Foundation; either version 2.1 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#ifndef _DVB_NET_H_ +#define _DVB_NET_H_ + +#include + +#include + +struct net_device; + +#define DVB_NET_DEVICES_MAX 10 + +#ifdef CONFIG_DVB_NET + +/** + * struct dvb_net - describes a DVB network interface + * + * @dvbdev: pointer to &struct dvb_device. + * @device: array of pointers to &struct net_device. + * @state: array of integers to each net device. A value + * different than zero means that the interface is + * in usage. + * @exit: flag to indicate when the device is being removed. + * @demux: pointer to &struct dmx_demux. + * @ioctl_mutex: protect access to this struct. + * @remove_mutex: mutex that avoids a race condition between a callback + * called when the hardware is disconnected and the + * file_operations of dvb_net. + * + * Currently, the core supports up to %DVB_NET_DEVICES_MAX (10) network + * devices. + */ + +struct dvb_net { + struct dvb_device *dvbdev; + struct net_device *device[DVB_NET_DEVICES_MAX]; + int state[DVB_NET_DEVICES_MAX]; + unsigned int exit:1; + struct dmx_demux *demux; + struct mutex ioctl_mutex; + struct mutex remove_mutex; +}; + +/** + * dvb_net_init - nitializes a digital TV network device and registers it. + * + * @adap: pointer to &struct dvb_adapter. + * @dvbnet: pointer to &struct dvb_net. + * @dmxdemux: pointer to &struct dmx_demux. + */ +int dvb_net_init(struct dvb_adapter *adap, struct dvb_net *dvbnet, + struct dmx_demux *dmxdemux); + +/** + * dvb_net_release - releases a digital TV network device and unregisters it. + * + * @dvbnet: pointer to &struct dvb_net. + */ +void dvb_net_release(struct dvb_net *dvbnet); + +#else + +struct dvb_net { + struct dvb_device *dvbdev; +}; + +static inline void dvb_net_release(struct dvb_net *dvbnet) +{ +} + +static inline int dvb_net_init(struct dvb_adapter *adap, + struct dvb_net *dvbnet, struct dmx_demux *dmx) +{ + return 0; +} + +#endif /* ifdef CONFIG_DVB_NET */ + +#endif -- cgit v1.3.1