Language: C
Label: vulnerable
CWE: CWE-190 \u2014 Integer Overflow or Wraparound
The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.

Code:
char* parse_content_length( char* buffer, char* end, int* length)
{
	int number;
	char *p;
	int  size;

	p = buffer;
	/* search the beginning of the number */
	while ( p<end && (*p==' ' || *p=='\t' || (*p=='\r' && *(p+1)=='\n') ||
	(*p=='\n' && (*(p+1)==' '||*(p+1)=='\t')) ))
		p++;
	if (p==end)
		goto error;
	/* parse the number */
	size = 0;
	number = 0;
	while (p<end && *p>='0' && *p<='9') {
		number = number*10 + (*p)-'0';
		if (number<0) {
			LM_ERR("number overflow at pos %d in len number [%.*s]\n",
				(int)(p-buffer),(int)(end-buffer), buffer);
			return 0;
		}
		size ++;
		p++;
	}
	if (p==end || size==0)
		goto error;
	/* now we should have only spaces at the end */
	while ( p<end && (*p==' ' || *p=='\t' ||
	(*p=='\n' && (*(p+1)==' '||*(p+1)=='\t')) ))
		p++;
	if (p==end)
		goto error;
	/* the header ends proper? */
	if ( (*(p++)!='\n') && (*(p-1)!='\r' || *(p++)!='\n' ) )
		goto error;

	*length = number;
	return p;
error:
	LM_ERR("parse error near char [%d][%c]\n",*p,*p);
	return 0;
}