From: Yu Kuai <yukuai3@xxxxxxxxxx> Changes in v3: - remove patch 3 from v2 - use rcu instead of a new lock Changes in v2: - fix a compile error for md-cluster in patch 2 - replace spin_lock/unlock with spin_lock/unlock_irq in patch 5 - don't wake up inside the new lock in md wakeup_thread in patch 5 Our test reports a uaf for 'mddev->sync_thread': T1 T2 md_start_sync md_register_thread raid1d md_check_recovery md_reap_sync_thread md_unregister_thread kfree md_wakeup_thread wake_up ->sync_thread was freed Currently, a global spinlock 'pers_lock' is borrowed to protect 'mddev->thread', this problem can be fixed likewise, however, there might be similar problem for other md_thread, and I really don't like the idea to borrow a global lock. This patchset do some refactor and use rcu to protect md_thread. Yu Kuai (3): md: pass a md_thread pointer to md_register_thread() md: refactor md_wakeup_thread() md: protect md_thread with rcu drivers/md/dm-raid.c | 4 +- drivers/md/md-bitmap.c | 6 +- drivers/md/md-cluster.c | 31 +++++---- drivers/md/md-multipath.c | 8 +-- drivers/md/md.c | 129 ++++++++++++++++++-------------------- drivers/md/md.h | 11 ++-- drivers/md/raid1.c | 15 +++-- drivers/md/raid10.c | 29 ++++----- drivers/md/raid5-cache.c | 17 +++-- drivers/md/raid5-ppl.c | 2 +- drivers/md/raid5.c | 45 +++++++------ 11 files changed, 139 insertions(+), 158 deletions(-) -- 2.39.2
