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 --- net/openvswitch/meter.h | 62 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 net/openvswitch/meter.h (limited to 'net/openvswitch/meter.h') diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h new file mode 100644 index 000000000..8bbf983cd --- /dev/null +++ b/net/openvswitch/meter.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2017 Nicira, Inc. + */ + +#ifndef METER_H +#define METER_H 1 + +#include +#include +#include +#include +#include +#include +#include + +#include "flow.h" +struct datapath; + +#define DP_MAX_BANDS 1 +#define DP_METER_ARRAY_SIZE_MIN BIT_ULL(10) +#define DP_METER_NUM_MAX (200000UL) + +struct dp_meter_band { + u32 type; + u32 rate; + u32 burst_size; + u64 bucket; /* 1/1000 packets, or in bits */ + struct ovs_flow_stats stats; +}; + +struct dp_meter { + spinlock_t lock; /* Per meter lock */ + struct rcu_head rcu; + u32 id; + u16 kbps:1, keep_stats:1; + u16 n_bands; + u32 max_delta_t; + u64 used; + struct ovs_flow_stats stats; + struct dp_meter_band bands[] __counted_by(n_bands); +}; + +struct dp_meter_instance { + struct rcu_head rcu; + u32 n_meters; + struct dp_meter __rcu *dp_meters[] __counted_by(n_meters); +}; + +struct dp_meter_table { + struct dp_meter_instance __rcu *ti; + u32 count; + u32 max_meters_allowed; +}; + +extern struct genl_family dp_meter_genl_family; +int ovs_meters_init(struct datapath *dp); +void ovs_meters_exit(struct datapath *dp); +bool ovs_meter_execute(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, u32 meter_id); + +#endif /* meter.h */ -- cgit v1.3.1