Pelted with rocks, who’s ending in dents all over? (6)
I believe the answer is:
stoned
'pelted with rocks' is the definition.
'who's ending in dents all over?' is the wordplay.
'ending' indicates one should take the final letters.
'in' indicates putting letters inside.
'all over?' is a reversal indicator (I've seen 'all over' mean this).
The last letter of 'who' is 'o'.
'o' going into 'dents' is 'denots'.
'denots' back-to-front is 'STONED'.
(Other definitions for stoned that I've seen before include "Plastered" , "Brutally punished" , "Incapable from drug-taking" , "on a trip" , "Slangily drunk or biblically executed" .)