Several pieces of Today, the shm code is written in such a way that AS structures it doesn't have a proc_t associated with it, hence causing 7477. Despite this, we should ensure that shm segments are operated upon when subject to this even if they lack don't have a proper a_proc association to process associated with the acting process. This was the cause of 7477, although shmat() exposes a means to partially bypass the null mapping secflag via seg_spt. Stronger enforcement of the a_proc proc invariant would ensure that the checks are consistently performed @valid_user_range@. address space in @valid_usr_range@.