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/file.h | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 fs/btrfs/file.h (limited to 'fs/btrfs/file.h') diff --git a/fs/btrfs/file.h b/fs/btrfs/file.h new file mode 100644 index 000000000..d7df81388 --- /dev/null +++ b/fs/btrfs/file.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef BTRFS_FILE_H +#define BTRFS_FILE_H + +#include + +struct file; +struct extent_state; +struct kiocb; +struct iov_iter; +struct inode; +struct folio; +struct page; +struct btrfs_ioctl_encoded_io_args; +struct btrfs_drop_extents_args; +struct btrfs_inode; +struct btrfs_root; +struct btrfs_path; +struct btrfs_replace_extent_info; +struct btrfs_trans_handle; + +extern const struct file_operations btrfs_file_operations; + +int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync); +int btrfs_drop_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct btrfs_inode *inode, + struct btrfs_drop_extents_args *args); +int btrfs_replace_file_extents(struct btrfs_inode *inode, + struct btrfs_path *path, const u64 start, + const u64 end, + struct btrfs_replace_extent_info *extent_info, + struct btrfs_trans_handle **trans_out); +int btrfs_mark_extent_written(struct btrfs_trans_handle *trans, + struct btrfs_inode *inode, u64 start, u64 end); +ssize_t btrfs_do_write_iter(struct kiocb *iocb, struct iov_iter *from, + const struct btrfs_ioctl_encoded_io_args *encoded); +int btrfs_release_file(struct inode *inode, struct file *file); +int btrfs_dirty_folio(struct btrfs_inode *inode, struct folio *folio, loff_t pos, + size_t write_bytes, struct extent_state **cached, bool noreserve); +int btrfs_fdatawrite_range(struct btrfs_inode *inode, loff_t start, loff_t end); +int btrfs_check_nocow_lock(struct btrfs_inode *inode, loff_t pos, + size_t *write_bytes, bool nowait); +void btrfs_check_nocow_unlock(struct btrfs_inode *inode); +bool btrfs_find_delalloc_in_range(struct btrfs_inode *inode, u64 start, u64 end, + struct extent_state **cached_state, + u64 *delalloc_start_ret, u64 *delalloc_end_ret); +int btrfs_write_check(struct kiocb *iocb, size_t count); +ssize_t btrfs_buffered_write(struct kiocb *iocb, struct iov_iter *i); + +#endif -- cgit v1.3.1