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/sysfs.h | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 fs/btrfs/sysfs.h (limited to 'fs/btrfs/sysfs.h') diff --git a/fs/btrfs/sysfs.h b/fs/btrfs/sysfs.h new file mode 100644 index 000000000..05498e534 --- /dev/null +++ b/fs/btrfs/sysfs.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef BTRFS_SYSFS_H +#define BTRFS_SYSFS_H + +#include +#include +#include + +struct block_device; +struct btrfs_fs_info; +struct btrfs_device; +struct btrfs_fs_devices; +struct btrfs_block_group; +struct btrfs_space_info; +struct btrfs_qgroup; + +enum btrfs_feature_set { + FEAT_COMPAT, + FEAT_COMPAT_RO, + FEAT_INCOMPAT, + FEAT_MAX +}; + +char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags); +const char *btrfs_feature_set_name(enum btrfs_feature_set set); +int btrfs_sysfs_add_device(struct btrfs_device *device); +void btrfs_sysfs_remove_device(struct btrfs_device *device); +int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs); +void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs); +void btrfs_sysfs_update_sprout_fsid(struct btrfs_fs_devices *fs_devices); +void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info); +void btrfs_kobject_uevent(struct block_device *bdev, enum kobject_action action); + +int __init btrfs_init_sysfs(void); +void __cold btrfs_exit_sysfs(void); +int btrfs_sysfs_add_mounted(struct btrfs_fs_info *fs_info); +void btrfs_sysfs_remove_mounted(struct btrfs_fs_info *fs_info); +void btrfs_sysfs_add_block_group_type(struct btrfs_block_group *cache); +int btrfs_sysfs_add_space_info_type(struct btrfs_space_info *space_info); +void btrfs_sysfs_remove_space_info(struct btrfs_space_info *space_info); +void btrfs_sysfs_update_devid(struct btrfs_device *device); + +int btrfs_sysfs_add_one_qgroup(struct btrfs_fs_info *fs_info, + struct btrfs_qgroup *qgroup); +void btrfs_sysfs_del_qgroups(struct btrfs_fs_info *fs_info); +int btrfs_sysfs_add_qgroups(struct btrfs_fs_info *fs_info); +void btrfs_sysfs_del_one_qgroup(struct btrfs_fs_info *fs_info, + struct btrfs_qgroup *qgroup); +int btrfs_read_policy_to_enum(const char *str, s64 *value); + +#ifdef CONFIG_BTRFS_EXPERIMENTAL +int __init btrfs_read_policy_init(void); +char *btrfs_get_mod_read_policy(void); +#endif + +#endif -- cgit v1.3.1