Date: Sun, 6 Aug 2023 20:36:24 GMT
From: Marius Strobl <marius@FreeBSD.org>
To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org
Subject: git: 3b0d328a2def - stable/13 - gif(4): Revert in{,6}_gif_output() misalignment handling
Message-ID: <202308062036.376KaOof042631@gitrepo.freebsd.org>
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The branch stable/13 has been updated by marius: URL: https://cgit.FreeBSD.org/src/commit/?id=3b0d328a2defb7a949f6ca5afd83281ceed1b6c8 commit 3b0d328a2defb7a949f6ca5afd83281ceed1b6c8 Author: Marius Strobl <marius@FreeBSD.org> AuthorDate: 2023-07-19 17:17:43 +0000 Commit: Marius Strobl <marius@FreeBSD.org> CommitDate: 2023-08-06 17:16:57 +0000 gif(4): Revert in{,6}_gif_output() misalignment handling The code added in c89c8a1029860182eece5d51ec09119b9500e5a1 in order to compensate possible misalignment caused by prepending the IP4/6 header with an EtherIP one got broken at some point by a rewrite of gif(4). For better or worse, 8018ac153f7671699ca008f31c0fad9caef2f531 relaxed the alignment of struct ip from 32 bit to 16 bit, though. As a result, a 16 bit offset of the IPv4 header induced by the addition of the 16 bit EtherIP one no longer is a problem in the first place. The alignment of struct ip6_hdr currently is even only 8 bit, making it even less problematic with regards to possible misalignment. Thus, remove the code for handling misalignment in in{,6}_gif_output() altogether again. While at it, replace the 3 bcopy(9) calls in gif(4) with memcpy(9) as there's no need to handle overlap here. (cherry picked from commit e82d7b2952afaf9625a3d7b05d03c43c1d3e7d9c) --- sys/net/if_gif.c | 2 +- sys/net/if_gif.h | 2 -- sys/netinet/in_gif.c | 19 ++----------------- sys/netinet6/in6_gif.c | 19 ++----------------- 4 files changed, 5 insertions(+), 37 deletions(-) diff --git a/sys/net/if_gif.c b/sys/net/if_gif.c index ea4b80690e50..4d2c1dcf091d 100644 --- a/sys/net/if_gif.c +++ b/sys/net/if_gif.c @@ -407,7 +407,7 @@ gif_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, uint32_t af; if (dst->sa_family == AF_UNSPEC) - bcopy(dst->sa_data, &af, sizeof(af)); + memcpy(&af, dst->sa_data, sizeof(af)); else af = RO_GET_FAMILY(ro, dst); /* diff --git a/sys/net/if_gif.h b/sys/net/if_gif.h index 2e61fcc166e1..f8fda6ddf801 100644 --- a/sys/net/if_gif.h +++ b/sys/net/if_gif.h @@ -94,8 +94,6 @@ struct etherip_header { } __packed; #define ETHERIP_VERSION 0x3 -/* mbuf adjust factor to force 32-bit alignment of IP header */ -#define ETHERIP_ALIGN 2 #define GIF_WAIT() epoch_wait_preempt(net_epoch_preempt) diff --git a/sys/netinet/in_gif.c b/sys/netinet/in_gif.c index a9f3d384fb5a..2caa9fcc23e2 100644 --- a/sys/netinet/in_gif.c +++ b/sys/netinet/in_gif.c @@ -272,31 +272,16 @@ in_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn) { struct gif_softc *sc = ifp->if_softc; struct ip *ip; - int len; /* prepend new IP header */ NET_EPOCH_ASSERT(); - len = sizeof(struct ip); -#ifndef __NO_STRICT_ALIGNMENT - if (proto == IPPROTO_ETHERIP) - len += ETHERIP_ALIGN; -#endif - M_PREPEND(m, len, M_NOWAIT); + M_PREPEND(m, sizeof(struct ip), M_NOWAIT); if (m == NULL) return (ENOBUFS); -#ifndef __NO_STRICT_ALIGNMENT - if (proto == IPPROTO_ETHERIP) { - len = mtod(m, vm_offset_t) & 3; - KASSERT(len == 0 || len == ETHERIP_ALIGN, - ("in_gif_output: unexpected misalignment")); - m->m_data += len; - m->m_len -= ETHERIP_ALIGN; - } -#endif ip = mtod(m, struct ip *); MPASS(sc->gif_family == AF_INET); - bcopy(sc->gif_iphdr, ip, sizeof(struct ip)); + memcpy(ip, sc->gif_iphdr, sizeof(struct ip)); ip->ip_p = proto; /* version will be set in ip_output() */ ip->ip_ttl = V_ip_gif_ttl; diff --git a/sys/netinet6/in6_gif.c b/sys/netinet6/in6_gif.c index 54cb81c6130f..eed311b86ff2 100644 --- a/sys/netinet6/in6_gif.c +++ b/sys/netinet6/in6_gif.c @@ -290,31 +290,16 @@ in6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn) { struct gif_softc *sc = ifp->if_softc; struct ip6_hdr *ip6; - int len; /* prepend new IP header */ NET_EPOCH_ASSERT(); - len = sizeof(struct ip6_hdr); -#ifndef __NO_STRICT_ALIGNMENT - if (proto == IPPROTO_ETHERIP) - len += ETHERIP_ALIGN; -#endif - M_PREPEND(m, len, M_NOWAIT); + M_PREPEND(m, sizeof(struct ip6_hdr), M_NOWAIT); if (m == NULL) return (ENOBUFS); -#ifndef __NO_STRICT_ALIGNMENT - if (proto == IPPROTO_ETHERIP) { - len = mtod(m, vm_offset_t) & 3; - KASSERT(len == 0 || len == ETHERIP_ALIGN, - ("in6_gif_output: unexpected misalignment")); - m->m_data += len; - m->m_len -= ETHERIP_ALIGN; - } -#endif ip6 = mtod(m, struct ip6_hdr *); MPASS(sc->gif_family == AF_INET6); - bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr)); + memcpy(ip6, sc->gif_ip6hdr, sizeof(struct ip6_hdr)); ip6->ip6_flow |= htonl((uint32_t)ecn << 20); ip6->ip6_nxt = proto;
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