Is "the mind is without feature or surface, limitless, ..." in the Pali canon?
There's a similar phrase (not an exact match) in DN 11:


  This is how the question should be asked:
  Evañca kho eso, bhikkhu, pañho pucchitabbo:
  
  85.11 “Where do water and earth,
  ‘Kattha āpo ca pathavī,
  
  85.12 fire and air find no footing;
  tejo vāyo na gādhati;
  
  85.13 where do long and short,
  Kattha dīghañca rassañca,
  
  85.14 fine and coarse, beautiful and ugly;
  aṇuṃ thūlaṃ subhāsubhaṃ;
  
  85.15 where do name and form
  Kattha nāmañca rūpañca,
  
  85.16 cease with nothing left over?”
  asesaṃ uparujjhatī’ti.
  
  85.17 And the answer to that is:
  Tatra veyyākaraṇaṃ bhavati:
  
  85.18 “Consciousness that’s invisible,
  ‘Viññāṇaṃ anidassanaṃ,
  
  85.19 infinite, radiant all round.
  anantaṃ sabbatopabhaṃ;


Maybe that it's it: if MN 11 was mistaken for DN 11; but it's not an exact match.

Even so I think that may be the Pali phrase you're looking for --


  Viññāṇaṃ anidassanaṃ, anantaṃ sabbatopabhaṃ


For example this (The Four Noble Truths and Noble Eightfold Path) translates these words as:


  Nirvana is a realm where corporeality and all the pairs of opposites - long and short, great and small, pure and impure - disappears and the mind is signless (anidassanam), boundless (anantam) and all-radiant (sabbato pabhamn). It is unchanging state (nibbanam accutam) of purity (suddhi), freedom (vimitti)  and  supreme happiness  (nibbanam paramam sukham).


... although that doesn't say which sutta[s] these words come from.

Another place that phrase appears is in MN 49 (but also not an exact match, i.e. "freed from the six-sense base" isn't part of the phrase there).