Although the attribute name length is checked before comparing it to
some common names (e.g., $I30), the offset isn't. This adds a sanity
check for the attribute name offset, guarantee the validity and prevent
possible out-of-bound memory accesses.
Signed-off-by: Edward Lo <edward.lo@ambergroup.io> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Signed-off-by: Sasha Levin <sashal@kernel.org>