[ubsan] Fix a faulty memory accessibility check
The dynamic type check needs to inspect vtables, but could crash if it
encounters a vtable pointer to inaccessible memory. In the first attempt
to fix the issue (r304437), we performed a memory accessibility check on
the wrong range of memory. This should *really* fix the problem.
Patch by Max Moroz!
Differential Revision: https://reviews.llvm.org/D34215
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@305489 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed
