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/nilfs2/cpfile.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 fs/nilfs2/cpfile.h (limited to 'fs/nilfs2/cpfile.h') diff --git a/fs/nilfs2/cpfile.h b/fs/nilfs2/cpfile.h new file mode 100644 index 000000000..f5b1d5928 --- /dev/null +++ b/fs/nilfs2/cpfile.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * NILFS checkpoint file. + * + * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. + * + * Written by Koji Sato. + */ + +#ifndef _NILFS_CPFILE_H +#define _NILFS_CPFILE_H + +#include +#include +#include /* nilfs_cpstat */ +#include /* nilfs_inode, nilfs_checkpoint */ + + +int nilfs_cpfile_read_checkpoint(struct inode *cpfile, __u64 cno, + struct nilfs_root *root, struct inode *ifile); +int nilfs_cpfile_create_checkpoint(struct inode *cpfile, __u64 cno); +int nilfs_cpfile_finalize_checkpoint(struct inode *cpfile, __u64 cno, + struct nilfs_root *root, __u64 blkinc, + time64_t ctime, bool minor); +int nilfs_cpfile_delete_checkpoints(struct inode *, __u64, __u64); +int nilfs_cpfile_delete_checkpoint(struct inode *, __u64); +int nilfs_cpfile_change_cpmode(struct inode *, __u64, int); +int nilfs_cpfile_is_snapshot(struct inode *, __u64); +int nilfs_cpfile_get_stat(struct inode *, struct nilfs_cpstat *); +ssize_t nilfs_cpfile_get_cpinfo(struct inode *, __u64 *, int, void *, + unsigned int, size_t); + +int nilfs_cpfile_read(struct super_block *sb, size_t cpsize, + struct nilfs_inode *raw_inode, struct inode **inodep); + +#endif /* _NILFS_CPFILE_H */ -- cgit v1.3.1