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/ntfs/sysctl.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 fs/ntfs/sysctl.h (limited to 'fs/ntfs/sysctl.h') diff --git a/fs/ntfs/sysctl.h b/fs/ntfs/sysctl.h new file mode 100644 index 000000000..037127c99 --- /dev/null +++ b/fs/ntfs/sysctl.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Defines for sysctl handling in NTFS Linux kernel driver. + * + * Copyright (C) 1997 Martin von Löwis, Régis Duchesne + * Copyright (c) 2002-2004 Anton Altaparmakov + */ + +#ifndef _LINUX_NTFS_SYSCTL_H +#define _LINUX_NTFS_SYSCTL_H + + +#if defined(DEBUG) && defined(CONFIG_SYSCTL) + +int ntfs_sysctl(int add); + +#else + +/* Just return success. */ +static inline int ntfs_sysctl(int add) +{ + return 0; +} + +#endif /* DEBUG && CONFIG_SYSCTL */ +#endif /* _LINUX_NTFS_SYSCTL_H */ -- cgit v1.3.1