st.c (rb_hash_bulk_insert_into_st_table): avoid out-of-bounds write
"hash_bulk_insert" first expands the table, but the target size was
wrong: it was calculated by "num_entries + (size to buld insert)", but
it was wrong when "num_entries < entries_bound", i.e., it has a deleted
entry. "hash_bulk_insert" adds the given entries from entries_bound,
which led to out-of-bounds write access. [Bug #15536]
As a simple fix, this commit changes the calculation to "entries_bound +
size". I'm afraid if this might be inefficient, but I think it is safe
anyway.
merge revision(s) 66832: [Backport #15536]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_6@66853 b2dd03c8-39d4-4d8f-98ff-823fe69b080e