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/rdma/ib_sysfs.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 include/rdma/ib_sysfs.h (limited to 'include/rdma/ib_sysfs.h') diff --git a/include/rdma/ib_sysfs.h b/include/rdma/ib_sysfs.h new file mode 100644 index 000000000..3b77cfd74 --- /dev/null +++ b/include/rdma/ib_sysfs.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ +/* + * Copyright (c) 2021 Mellanox Technologies Ltd. All rights reserved. + */ +#ifndef DEF_RDMA_IB_SYSFS_H +#define DEF_RDMA_IB_SYSFS_H + +#include + +struct ib_device; + +struct ib_port_attribute { + struct attribute attr; + ssize_t (*show)(struct ib_device *ibdev, u32 port_num, + struct ib_port_attribute *attr, char *buf); + ssize_t (*store)(struct ib_device *ibdev, u32 port_num, + struct ib_port_attribute *attr, const char *buf, + size_t count); +}; + +#define IB_PORT_ATTR_RW(_name) \ + struct ib_port_attribute ib_port_attr_##_name = __ATTR_RW(_name) + +#define IB_PORT_ATTR_ADMIN_RW(_name) \ + struct ib_port_attribute ib_port_attr_##_name = \ + __ATTR_RW_MODE(_name, 0600) + +#define IB_PORT_ATTR_RO(_name) \ + struct ib_port_attribute ib_port_attr_##_name = __ATTR_RO(_name) + +#define IB_PORT_ATTR_WO(_name) \ + struct ib_port_attribute ib_port_attr_##_name = __ATTR_WO(_name) + +struct ib_device *ib_port_sysfs_get_ibdev_kobj(struct kobject *kobj, + u32 *port_num); + +#endif -- cgit v1.3.1