*** a/src/backend/utils/adt/misc.c
--- b/src/backend/utils/adt/misc.c
***************
*** 112,118 **** pg_signal_backend(int pid, int sig)
  		return SIGNAL_BACKEND_ERROR;
  	}
  
! 	if (!(superuser() || proc->roleId == GetUserId()))
  		return SIGNAL_BACKEND_NOPERMISSION;
  
  	/*
--- 112,125 ----
  		return SIGNAL_BACKEND_ERROR;
  	}
  
! 	/*
! 	 * Superuser can send signal without restriction, owner can send signals to all
! 	 * users attached to owned databases without superuser, others can signals only to
! 	 * sessions with same account.
! 	 */
! 	if (!(superuser() || proc->roleId == GetUserId()
! 		    || (pg_database_ownercheck(proc->databaseId, GetUserId())
! 						    && !superuser_arg(proc->roleId))))
  		return SIGNAL_BACKEND_NOPERMISSION;
  
  	/*
***************
*** 151,157 **** pg_cancel_backend(PG_FUNCTION_ARGS)
  	if (r == SIGNAL_BACKEND_NOPERMISSION)
  		ereport(ERROR,
  				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
! 				 (errmsg("must be superuser or have the same role to cancel queries running in other server processes"))));
  
  	PG_RETURN_BOOL(r == SIGNAL_BACKEND_SUCCESS);
  }
--- 158,164 ----
  	if (r == SIGNAL_BACKEND_NOPERMISSION)
  		ereport(ERROR,
  				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
! 				 (errmsg("must be superuser or database owner or have the same role to cancel queries running in other server processes"))));
  
  	PG_RETURN_BOOL(r == SIGNAL_BACKEND_SUCCESS);
  }
***************
*** 168,174 **** pg_terminate_backend(PG_FUNCTION_ARGS)
  	if (r == SIGNAL_BACKEND_NOPERMISSION)
  		ereport(ERROR,
  				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
! 				 (errmsg("must be superuser or have the same role to terminate other server processes"))));
  
  	PG_RETURN_BOOL(r == SIGNAL_BACKEND_SUCCESS);
  }
--- 175,181 ----
  	if (r == SIGNAL_BACKEND_NOPERMISSION)
  		ereport(ERROR,
  				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
! 				 (errmsg("must be superuser or database owner or have the same role to terminate other server processes"))));
  
  	PG_RETURN_BOOL(r == SIGNAL_BACKEND_SUCCESS);
  }
*** a/src/backend/utils/adt/pgstatfuncs.c
--- b/src/backend/utils/adt/pgstatfuncs.c
***************
*** 656,663 **** pg_stat_get_activity(PG_FUNCTION_ARGS)
  		else
  			nulls[3] = true;
  
! 		/* Values only available to same user or superuser */
! 		if (superuser() || beentry->st_userid == GetUserId())
  		{
  			switch (beentry->st_state)
  			{
--- 656,664 ----
  		else
  			nulls[3] = true;
  
! 		/* Values only available to same user or superuser or owner */
! 		if (superuser() || beentry->st_userid == GetUserId()
! 				    || pg_database_ownercheck(beentry->st_databaseid, GetUserId()))
  		{
  			switch (beentry->st_state)
  			{