git: 56dddebc5549 - main - ip6_input: Remove unused check for IPv4-compatible IPv6

The branch main has been updated by pouria:

URL: https://cgit.FreeBSD.org/src/commit/?id=56dddebc55494fdf75eeb914cc9e345d0d762f8c

commit 56dddebc55494fdf75eeb914cc9e345d0d762f8c
Author:     Pouria Mousavizadeh Tehrani <pouria@FreeBSD.org>
AuthorDate: 2026-03-19 18:15:10 +0000
Commit:     Pouria Mousavizadeh Tehrani <pouria@FreeBSD.org>
CommitDate: 2026-03-19 18:17:53 +0000

    ip6_input: Remove unused check for IPv4-compatible IPv6
    
    IPv4-compatible IPv6 addresses are deprecated by RFC 4291.
    No functional change intended.
    
    Reviewed by: glebius, emaste
    Differential Revision: https://reviews.freebsd.org/D55387
---
 sys/netinet6/ip6_input.c | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index acb690c2033d..20b092cf6fd2 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -683,21 +683,6 @@ ip6_input(struct mbuf *m)
 		in6_ifstat_inc(rcvif, ifs6_in_addrerr);
 		goto bad;
 	}
-#if 0
-	/*
-	 * Reject packets with IPv4 compatible addresses (auto tunnel).
-	 *
-	 * The code forbids auto tunnel relay case in RFC1933 (the check is
-	 * stronger than RFC1933).  We may want to re-enable it if mech-xx
-	 * is revised to forbid relaying case.
-	 */
-	if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
-	    IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
-		IP6STAT_INC(ip6s_badscope);
-		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
-		goto bad;
-	}
-#endif
 	/*
 	 * Try to forward the packet, but if we fail continue.
 	 * ip6_tryforward() does not generate redirects, so fall