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 --- fs/nfs/nfs4trace.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 fs/nfs/nfs4trace.c (limited to 'fs/nfs/nfs4trace.c') diff --git a/fs/nfs/nfs4trace.c b/fs/nfs/nfs4trace.c new file mode 100644 index 000000000..3fdc013f5 --- /dev/null +++ b/fs/nfs/nfs4trace.c @@ -0,0 +1,40 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2013 Trond Myklebust + */ +#include +#include +#include +#include "nfs4_fs.h" +#include "internal.h" +#include "nfs4session.h" +#include "callback.h" +#include "pnfs.h" + +#define CREATE_TRACE_POINTS +#include "nfs4trace.h" + +EXPORT_TRACEPOINT_SYMBOL_GPL(nfs4_pnfs_read); +EXPORT_TRACEPOINT_SYMBOL_GPL(nfs4_pnfs_write); +EXPORT_TRACEPOINT_SYMBOL_GPL(nfs4_pnfs_commit_ds); + +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_pg_init_read); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_pg_init_write); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_pg_get_mirror_count); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_read_done); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_write_done); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_read_pagelist); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_write_pagelist); +EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_ds_connect); + +EXPORT_TRACEPOINT_SYMBOL_GPL(ff_layout_read_error); +EXPORT_TRACEPOINT_SYMBOL_GPL(ff_layout_write_error); +EXPORT_TRACEPOINT_SYMBOL_GPL(ff_layout_commit_error); + +EXPORT_TRACEPOINT_SYMBOL_GPL(bl_ext_tree_prepare_commit); +EXPORT_TRACEPOINT_SYMBOL_GPL(bl_pr_key_reg); +EXPORT_TRACEPOINT_SYMBOL_GPL(bl_pr_key_reg_err); +EXPORT_TRACEPOINT_SYMBOL_GPL(bl_pr_key_unreg); +EXPORT_TRACEPOINT_SYMBOL_GPL(bl_pr_key_unreg_err); + +EXPORT_TRACEPOINT_SYMBOL_GPL(fl_getdevinfo); -- cgit v1.3.1