Author: tuexen Date: Wed Sep 25 10:38:44 2019 New Revision: 352672 URL: https://svnweb.freebsd.org/changeset/base/352672
Log: MFC r352511: When processing an incoming IPv6 packet over the loopback interface which contains Hop-by-Hop options, the mbuf chain is potentially changed in ip6_hopopts_input(), called by ip6_input_hbh(). This can happen, because of the the use of IP6_EXTHDR_CHECK, which might call m_pullup(). So provide the updated pointer back to the called of ip6_input_hbh() to avoid using a freed mbuf chain in`ip6_input()`. Reviewed by: markj@ Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D21664 Modified: stable/12/sys/netinet6/ip6_input.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/netinet6/ip6_input.c ============================================================================== --- stable/12/sys/netinet6/ip6_input.c Wed Sep 25 07:51:30 2019 (r352671) +++ stable/12/sys/netinet6/ip6_input.c Wed Sep 25 10:38:44 2019 (r352672) @@ -404,20 +404,22 @@ VNET_SYSUNINIT(inet6, SI_SUB_PROTO_DOMAIN, SI_ORDER_TH #endif static int -ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off, +ip6_input_hbh(struct mbuf **mp, uint32_t *plen, uint32_t *rtalert, int *off, int *nxt, int *ours) { + struct mbuf *m; struct ip6_hdr *ip6; struct ip6_hbh *hbh; - if (ip6_hopopts_input(plen, rtalert, &m, off)) { + if (ip6_hopopts_input(plen, rtalert, mp, off)) { #if 0 /*touches NULL pointer*/ - in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); + in6_ifstat_inc((*mp)->m_pkthdr.rcvif, ifs6_in_discard); #endif goto out; /* m have already been freed */ } /* adjust pointer */ + m = *mp; ip6 = mtod(m, struct ip6_hdr *); /* @@ -857,7 +859,7 @@ passin: */ plen = (u_int32_t)ntohs(ip6->ip6_plen); if (ip6->ip6_nxt == IPPROTO_HOPOPTS) { - if (ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours) != 0) + if (ip6_input_hbh(&m, &plen, &rtalert, &off, &nxt, &ours) != 0) return; } else nxt = ip6->ip6_nxt; _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
