Code: wb_prep(netdissect_options *ndo,
        const struct pkt_prep *prep, u_int len)
{
	int n;
	const struct pgstate *ps;
	const u_char *ep = ndo->ndo_snapend;

	ND_PRINT((ndo, " wb-prep:"));
	if (len < sizeof(*prep)) {
		return (-1);
 	}
 	n = EXTRACT_32BITS(&prep->pp_n);
 	ps = (const struct pgstate *)(prep + 1);
	while (--n >= 0 && !ND_TTEST(*ps)) {
 		const struct id_off *io, *ie;
 		char c = '<';
 
		ND_PRINT((ndo, " %u/%s:%u",
		    EXTRACT_32BITS(&ps->slot),
 		    ipaddr_string(ndo, &ps->page.p_sid),
 		    EXTRACT_32BITS(&ps->page.p_uid)));
 		io = (struct id_off *)(ps + 1);
		for (ie = io + ps->nid; io < ie && !ND_TTEST(*io); ++io) {
 			ND_PRINT((ndo, "%c%s:%u", c, ipaddr_string(ndo, &io->id),
 			    EXTRACT_32BITS(&io->off)));
 			c = ',';
		}
		ND_PRINT((ndo, ">"));
		ps = (struct pgstate *)io;
	}
	return ((u_char *)ps <= ep? 0 : -1);
}

Vulnerability Type: DoS 
CWE ID: CWE-20
Summary: print-wb.c in tcpdump before 4.7.4 allows remote attackers to cause a denial of service (segmentation fault and process crash).
Commit Message: whiteboard: fixup a few reversed tests (GH #446)

This is a follow-up to commit 3a3ec26.