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/raid-stripe-tree.h | 60 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 fs/btrfs/raid-stripe-tree.h (limited to 'fs/btrfs/raid-stripe-tree.h') diff --git a/fs/btrfs/raid-stripe-tree.h b/fs/btrfs/raid-stripe-tree.h new file mode 100644 index 000000000..69942ad43 --- /dev/null +++ b/fs/btrfs/raid-stripe-tree.h @@ -0,0 +1,60 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2023 Western Digital Corporation or its affiliates. + */ + +#ifndef BTRFS_RAID_STRIPE_TREE_H +#define BTRFS_RAID_STRIPE_TREE_H + +#include +#include +#include "fs.h" +#include "accessors.h" + +#define BTRFS_RST_SUPP_BLOCK_GROUP_MASK (BTRFS_BLOCK_GROUP_DUP | \ + BTRFS_BLOCK_GROUP_RAID1_MASK | \ + BTRFS_BLOCK_GROUP_RAID0 | \ + BTRFS_BLOCK_GROUP_RAID10) + +struct btrfs_io_context; +struct btrfs_io_stripe; +struct btrfs_fs_info; +struct btrfs_ordered_extent; +struct btrfs_trans_handle; + +int btrfs_delete_raid_extent(struct btrfs_trans_handle *trans, u64 start, u64 length); +int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info, + u64 logical, u64 *length, u64 map_type, + u32 stripe_index, struct btrfs_io_stripe *stripe); +int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans, + struct btrfs_ordered_extent *ordered_extent); + +#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS +int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans, + struct btrfs_io_context *bioc); +#endif + +static inline bool btrfs_need_stripe_tree_update(struct btrfs_fs_info *fs_info, + u64 map_type) +{ + u64 type = map_type & BTRFS_BLOCK_GROUP_TYPE_MASK; + u64 profile = map_type & BTRFS_BLOCK_GROUP_PROFILE_MASK; + + if (!btrfs_fs_incompat(fs_info, RAID_STRIPE_TREE)) + return false; + + if (type != BTRFS_BLOCK_GROUP_DATA) + return false; + + if (profile & BTRFS_RST_SUPP_BLOCK_GROUP_MASK) + return true; + + return false; +} + +static inline int btrfs_num_raid_stripes(u32 item_size) +{ + return item_size / sizeof(struct btrfs_raid_stride); +} + +#endif -- cgit v1.3.1