diff options
| author | rwatson <rwatson@FreeBSD.org> | 2014-10-12 15:49:52 +0000 |
|---|---|---|
| committer | rwatson <rwatson@FreeBSD.org> | 2014-10-12 15:49:52 +0000 |
| commit | 9532a34956eebfbc46d32db0a73a33a09ff42fb8 (patch) | |
| tree | 3d1cc176a1a9d02914a169d4a5df66a82f05c1b7 /sys/netinet | |
| parent | 2791f385b984a34d6a9ec9d1a14314a9d323d57f (diff) | |
| download | FreeBSD-src-9532a34956eebfbc46d32db0a73a33a09ff42fb8.zip FreeBSD-src-9532a34956eebfbc46d32db0a73a33a09ff42fb8.tar.gz | |
When deciding whether to call m_pullup() even though there is adequate
data in an mbuf, use M_WRITABLE() instead of a direct test of M_EXT;
the latter both unnecessarily exposes mbuf-allocator internals in the
protocol stack and is also insufficient to catch all cases of
non-writability.
(NB: m_pullup() does not actually guarantee that a writable mbuf is
returned, so further refinement of all of these code paths continues to
be required.)
Reviewed by: bz
MFC after: 3 days
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D900
Diffstat (limited to 'sys/netinet')
| -rw-r--r-- | sys/netinet/igmp.c | 4 | ||||
| -rw-r--r-- | sys/netinet/ip_mroute.c | 7 | ||||
| -rw-r--r-- | sys/netinet/ip_output.c | 2 |
3 files changed, 6 insertions, 7 deletions
diff --git a/sys/netinet/igmp.c b/sys/netinet/igmp.c index a13260f..529d0ab 100644 --- a/sys/netinet/igmp.c +++ b/sys/netinet/igmp.c @@ -1466,7 +1466,7 @@ igmp_input(struct mbuf **mp, int *offp, int proto) minlen += IGMP_V3_QUERY_MINLEN; else minlen += IGMP_MINLEN; - if ((m->m_flags & M_EXT || m->m_len < minlen) && + if ((!M_WRITABLE(m) || m->m_len < minlen) && (m = m_pullup(m, minlen)) == 0) { IGMPSTAT_INC(igps_rcv_tooshort); return (IPPROTO_DONE); @@ -1557,7 +1557,7 @@ igmp_input(struct mbuf **mp, int *offp, int proto) */ igmpv3len = iphlen + IGMP_V3_QUERY_MINLEN + srclen; - if ((m->m_flags & M_EXT || + if ((!M_WRITABLE(m) || m->m_len < igmpv3len) && (m = m_pullup(m, igmpv3len)) == NULL) { IGMPSTAT_INC(igps_rcv_tooshort); diff --git a/sys/netinet/ip_mroute.c b/sys/netinet/ip_mroute.c index 05605a8..7239946 100644 --- a/sys/netinet/ip_mroute.c +++ b/sys/netinet/ip_mroute.c @@ -121,7 +121,6 @@ __FBSDID("$FreeBSD$"); #endif #define VIFI_INVALID ((vifi_t) -1) -#define M_HASCL(m) ((m)->m_flags & M_EXT) static VNET_DEFINE(uint32_t, last_tv_sec); /* last time we processed this */ #define V_last_tv_sec VNET(last_tv_sec) @@ -1304,7 +1303,7 @@ X_ip_mforward(struct ip *ip, struct ifnet *ifp, struct mbuf *m, } mb0 = m_copypacket(m, M_NOWAIT); - if (mb0 && (M_HASCL(mb0) || mb0->m_len < hlen)) + if (mb0 && (!M_WRITABLE(mb0) || mb0->m_len < hlen)) mb0 = m_pullup(mb0, hlen); if (mb0 == NULL) { free(rte, M_MRTABLE); @@ -1544,7 +1543,7 @@ ip_mdq(struct mbuf *m, struct ifnet *ifp, struct mfc *rt, vifi_t xmt_vif) int hlen = ip->ip_hl << 2; struct mbuf *mm = m_copy(m, 0, hlen); - if (mm && (M_HASCL(mm) || mm->m_len < hlen)) + if (mm && (!M_WRITABLE(mm) || mm->m_len < hlen)) mm = m_pullup(mm, hlen); if (mm == NULL) return ENOBUFS; @@ -1665,7 +1664,7 @@ phyint_send(struct ip *ip, struct vif *vifp, struct mbuf *m) * so that ip_output() only scribbles on the copy. */ mb_copy = m_copypacket(m, M_NOWAIT); - if (mb_copy && (M_HASCL(mb_copy) || mb_copy->m_len < hlen)) + if (mb_copy && (!M_WRITABLE(mb_copy) || mb_copy->m_len < hlen)) mb_copy = m_pullup(mb_copy, hlen); if (mb_copy == NULL) return; diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c index 827d25a..25e7cce 100644 --- a/sys/netinet/ip_output.c +++ b/sys/netinet/ip_output.c @@ -1365,7 +1365,7 @@ ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, * modify the pack in order to generate checksums. */ copym = m_dup(m, M_NOWAIT); - if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) + if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen)) copym = m_pullup(copym, hlen); if (copym != NULL) { /* If needed, compute the checksum and mark it as valid. */ |
