Merge tag 'vfs.misc.fixes.v6.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping

Pull vfs fix from Christian Brauner:
"When a mount or mount tree is made shared the vfs allocates new peer
group ids for all mounts that have no peer group id set. Only mounts
that aren't marked with MNT_SHARED are relevant here as MNT_SHARED
indicates that the mount has fully transitioned to a shared mount. The
peer group id handling is done with namespace lock held.

On failure, the peer group id settings of mounts for which a new peer
group id was allocated need to be reverted and the allocated peer
group id freed. The cleanup_group_ids() helper can identify the mounts
to cleanup by checking whether a given mount has a peer group id set
but isn't marked MNT_SHARED. The deallocation always needs to happen
with namespace lock held to protect against concurrent modifications
of the propagation settings.

This fixes the one place where the namespace lock was dropped before
calling cleanup_group_ids()"

* tag 'vfs.misc.fixes.v6.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping:
fs: drop peer group ids under namespace lock