core: Reject invalid values of LimitXMLRequestBody.

[arturobernalg]

set_limit_xml_req_body() used atol(), so "abc123" and "123abc" were accepted as 0 and 123, and overflows were silently clamped. Parse the whole argument with apr_strtoff() like LimitRequestBody, and reject values that do not fit in limit_xml_body or exceed AP_MAX_LIMIT_XML_BODY. BZ 69975.

---

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[notroj]

+1 though we really could do with having one function for turning config input into an apr_off_t, like ap_timeout_parameter_parse , there are a bunch of places this is done inconsistently likely.

[arturobernalg]

Thanks. Agreed, a single helper to parse a config value into an apr_off_t would be better than what we have now. I checked the current callers, and several of them (the cache modules, mod_buffer, mod_auth_form, mod_dav_fs, mod_cgi) accept trailing characters, or have no checks at all. I'll look at that as a separate change, so this one can stay as it is.