[master] b2bbb50 Neuter another case where AddressSanitizer chokes on FreeBSD's hyperwide memcmp()

[Poul-Henning Kamp]

commit b2bbb5051c691eeed3373af0eeff3448a94b2867
Author: Poul-Henning Kamp <phk at FreeBSD.org>
Date:   Tue Feb 2 00:26:39 2016 +0000

    Neuter another case where AddressSanitizer chokes on FreeBSD's
    hyperwide memcmp()

diff --git a/bin/varnishd/cache/cache_ban.c b/bin/varnishd/cache/cache_ban.c
index 2b71d94..2838914 100644
--- a/bin/varnishd/cache/cache_ban.c
+++ b/bin/varnishd/cache/cache_ban.c
@@ -143,10 +143,10 @@ ban_equal(const uint8_t *bs1, const uint8_t *bs2)
 
 	/*
 	 * Compare two ban-strings.
-	 * The memcmp() is safe because the first field we compare is the
-	 * length and that is part of the fixed header structure.
 	 */
 	u = vbe32dec(bs1 + BANS_LENGTH);
+	if (u != vbe32dec(bs2 + BANS_LENGTH))
+		return (0);
 	return (!memcmp(bs1 + BANS_LENGTH, bs2 + BANS_LENGTH, u - BANS_LENGTH));
 }