diff options
| -rw-r--r-- | sys/net/if_tun.c | 71 |
1 files changed, 50 insertions, 21 deletions
diff --git a/sys/net/if_tun.c b/sys/net/if_tun.c index aaef6111ee3..e9f707ece86 100644 --- a/sys/net/if_tun.c +++ b/sys/net/if_tun.c @@ -1,4 +1,4 @@ -/* $OpenBSD: if_tun.c,v 1.248 2024/11/17 23:21:45 dlg Exp $ */ +/* $OpenBSD: if_tun.c,v 1.249 2024/11/17 23:31:01 dlg Exp $ */ /* $NetBSD: if_tun.c,v 1.24 1996/05/07 02:40:48 thorpej Exp $ */ /* @@ -922,9 +922,9 @@ tun_dev_write(dev_t dev, struct uio *uio, int ioflag, int align) { struct tun_softc *sc; struct ifnet *ifp; - struct mbuf *m0; + struct mbuf *m0, *m, *n; int error = 0; - size_t mlen; + size_t len, alen, mlen; size_t hlen; struct tun_hdr th; @@ -938,30 +938,16 @@ tun_dev_write(dev_t dev, struct uio *uio, int ioflag, int align) if (ISSET(sc->sc_flags, TUN_HDR)) hlen += sizeof(th); if (uio->uio_resid < hlen || - uio->uio_resid > (hlen + ifp->if_hardmtu)) { + uio->uio_resid > (hlen + MAXMCLBYTES)) { error = EMSGSIZE; goto put; } - align += max_linkhdr; - mlen = align + uio->uio_resid; - m0 = m_gethdr(M_DONTWAIT, MT_DATA); if (m0 == NULL) { error = ENOMEM; goto put; } - if (mlen > MHLEN) { - m_clget(m0, M_DONTWAIT, mlen); - if (!ISSET(m0->m_flags, M_EXT)) { - error = ENOMEM; - goto drop; - } - } - - m_align(m0, mlen); - m0->m_pkthdr.len = m0->m_len = mlen; - m_adj(m0, align); if (ISSET(sc->sc_flags, TUN_HDR)) { error = uiomove(&th, sizeof(th), uio); @@ -1009,9 +995,52 @@ tun_dev_write(dev_t dev, struct uio *uio, int ioflag, int align) } } - error = uiomove(mtod(m0, void *), m0->m_len, uio); - if (error != 0) - goto drop; + align += roundup(max_linkhdr, sizeof(long)); + mlen = MHLEN; /* how much space in the mbuf */ + + len = uio->uio_resid; + m0->m_pkthdr.len = len; + + m = m0; + for (;;) { + alen = align + len; /* what we want to put in this mbuf */ + if (alen > mlen) { + if (alen > MAXMCLBYTES) + alen = MAXMCLBYTES; + m_clget(m, M_DONTWAIT, alen); + if (!ISSET(m->m_flags, M_EXT)) { + error = ENOMEM; + goto put; + } + } + + m->m_len = alen; + if (align > 0) { + /* avoid m_adj to protect m0->m_pkthdr.len */ + m->m_data += align; + m->m_len -= align; + } + + error = uiomove(mtod(m, void *), m->m_len, uio); + if (error != 0) + goto drop; + + len = uio->uio_resid; + if (len == 0) + break; + + n = m_get(M_DONTWAIT, MT_DATA); + if (n == NULL) { + error = ENOMEM; + goto put; + } + + align = 0; + mlen = MLEN; + + m->m_next = n; + m = n; + } NET_LOCK(); if_vinput(ifp, m0); |