[PATCH 03/16] tcp: False "Untrusted loop bound" positive, CWE-606

Field doff in struct tcp_hdr is 4 bits wide, so optlen in tcp_tap_handler() is already bound, but make that explicit. Reported by Coverity. Signed-off-by: Stefano Brivio --- tcp.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tcp.c b/tcp.c index 1409c53..858eb41 100644 --- a/tcp.c +++ b/tcp.c @@ -2716,6 +2716,8 @@ int tcp_tap_handler(struct ctx *c, int af, const void *addr, return 1; optlen = th->doff * 4UL - sizeof(*th); + /* Static checkers might fail to see this: */ + optlen = MIN(optlen, ((1UL << 4) /* from doff width */ - 6) * 4UL); opts = packet_get(p, 0, sizeof(*th), optlen, NULL); conn = tcp_hash_lookup(c, af, addr, htons(th->source), htons(th->dest)); -- 2.35.1