eb42305f (jit: avoid integer wraparound in stack size definition (#42),
2021-11-19) introduces a check to avoid an integer overflow when
allocating stack size for JIT.
Unfortunately the maximum value was using PCRE2_SIZE_MAX, eventhough
the variable is of type size_t, so correct it.
Practically; the issue shouldn't affect the most common configurations
where both values are the same, and it will be unlikely that there would
be a configuration where PCRE2_SIZE_MAX > SIZE_MAX, hence the mistake
is unlikely to have reintroduced the original bug and this change should
be therefore mostly equivalent.
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
pcre2_jit_stack_create() allows the user to indicate how big of a
stack size JIT should be able to allocate and use, using a size_t
variable which should be able to hold bigger values than reasonable.
Internally, the value is rounded to the next 8K, but if the value
is unreasonable large, would overflow and could result in a smaller
than expected stack or a maximun size that is smaller than the
minimum..
Avoid the overflow by checking the value and failing early, and
while at it make the check clearer while documenting the failure
mode.
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Carlo Marcelo Arenas Belón
Zoltán Herczeg
Philip.Hazel