Description:
------------
logical_filters.c uses following macro in filter_private.h for trimming strings.

#define PHP_FILTER_TRIM_DEFAULT_EX(p, len, return_if_empty) { \
	while ((len > 0)  && (*p == ' ' || *p == '\t' || *p == '\r' || *p == '\v' || *p == '\n')) { \
		p++; \
		len--; \
	} \
	if (len < 1 && return_if_empty) { \
		RETURN_VALIDATION_FAILED("Filter validated value became empty after trim", 0); \
	} \
	if (len > 0) { \
		while (p[len-1] == ' ' || p[len-1] == '\t' || p[len-1] == '\r' || p[len-1] == '\v' || p[len-1] == '\n') { \
			len--; \
		} \
	} \
}

As you can see by the code, trailing spaces are not trimmed, but it only shorten length by counting spaces in it.

e.g. ' 1234  5678' would result in unwanted condition.