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Pull vfs fixes from Christian Brauner: - Don't warn when a mount is completed from another user namespace. fsopen() records the caller's user namespace in fc->user_ns and hands back an ordinary file descriptor. The task that calls fsconfig(FSCONFIG_CMD_CREATE) doesn't have to be the one that created the context, and mount_capable() lets it through as long as the caller has CAP_SYS_ADMIN over fc->user_ns, which anyone in an ancestor namespace does. So fc->user_ns != current_user_ns() is something an unprivileged user can arrange. Both overlayfs and binfmt_misc WARN_ON() that. Overlayfs already has the same check as a plain error return in ovl_parse_param(). Drop the WARN_ON() and just refuse. Add selftests for both cases. - Reject pid allocations through dead ancestor pid namespaces. Require PIDNS_ADDING in every namespace that will receive the pid before publishing any of them. That preserves the invariant that free_pid() never decrements pid_allocated in a namespace whose child_reaper is no longer live. The existing ENOMEM behavior is unchanged. * tag 'vfs-7.2-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: pid: reject allocations through dead ancestor pid namespaces selftests/filesystems: test completing a context from another user namespace binfmt_misc: don't warn when the mount is completed from another user namespace ovl: don't warn when the mount is completed from another user namespace