check_unsafe_exec: s/lock_task_sighand/rcu_read_lock/
write_lock(¤t->fs->lock) guarantees we can't wrongly miss LSM_UNSAFE_SHARE, this is what we care about. Use rcu_read_lock() instead of ->siglock to iterate over the sub-threads. We must see all CLONE_THREAD|CLONE_FS threads which didn't pass exit_fs(), it takes fs->lock too. With or without this patch we can miss the freshly cloned thread and set LSM_UNSAFE_SHARE, we don't care. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Roland McGrath <roland@redhat.com> [ Fixed lock/unlock typo - Hugh ] Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing
Please register or sign in to comment