tree 5dd21cd821de750226867a3132ad1b03660af8bd
parent 32df16c45403abcb156bc4ada67cc3521226e63e
author Andrew Jeffery <andrew@codeconstruct.com.au> 1715921234 +0930
committer vkaverap@in.ibm.com <vkaverap@in.ibm.com> 1716199574 -0500

msgbuf: Rework detection of invalid memory regions

From Annex J.2 of N2176 (C17 draft specification):

> Addition or subtraction of a pointer into, or just beyond, an array
> object and an integer type produces a result that does not point into,
> or just beyond, the same array object (6.5.6).

Instead we can lean on uintptr_t from 7.20.1.4, and from there the
defined behavior of unsigned overflow.

Change-Id: Ia1b47b87efeb9c96057d294a3e38e90bfdba5386
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>