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/btrfs/props.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 fs/btrfs/props.h (limited to 'fs/btrfs/props.h') diff --git a/fs/btrfs/props.h b/fs/btrfs/props.h new file mode 100644 index 000000000..15d9a025c --- /dev/null +++ b/fs/btrfs/props.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2014 Filipe David Borba Manana + */ + +#ifndef BTRFS_PROPS_H +#define BTRFS_PROPS_H + +#include +#include + +struct btrfs_inode; +struct btrfs_path; +struct btrfs_trans_handle; + +int __init btrfs_props_init(void); + +int btrfs_set_prop(struct btrfs_trans_handle *trans, struct btrfs_inode *inode, + const char *name, const char *value, size_t value_len, + int flags); +int btrfs_validate_prop(const struct btrfs_inode *inode, const char *name, + const char *value, size_t value_len); +bool btrfs_ignore_prop(const struct btrfs_inode *inode, const char *name); + +int btrfs_load_inode_props(struct btrfs_inode *inode, struct btrfs_path *path); + +int btrfs_inode_inherit_props(struct btrfs_trans_handle *trans, + struct btrfs_inode *inode, + const struct btrfs_inode *dir); + +#endif -- cgit v1.3.1