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| 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/netinet6/ip6_mroute.c | |
| 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/netinet6/ip6_mroute.c')
| -rw-r--r-- | sys/netinet6/ip6_mroute.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/sys/netinet6/ip6_mroute.c b/sys/netinet6/ip6_mroute.c index daf43f6..3976b08 100644 --- a/sys/netinet6/ip6_mroute.c +++ b/sys/netinet6/ip6_mroute.c @@ -126,9 +126,6 @@ __FBSDID("$FreeBSD$"); static MALLOC_DEFINE(M_MRTABLE6, "mf6c", "multicast forwarding cache entry"); -/* XXX: this is a very common idiom; move to <sys/mbuf.h> ? */ -#define M_HASCL(m) ((m)->m_flags & M_EXT) - static int ip6_mdq(struct mbuf *, struct ifnet *, struct mf6c *); static void phyint_send(struct ip6_hdr *, struct mif6 *, struct mbuf *); static int register_send(struct ip6_hdr *, struct mif6 *, struct mbuf *); @@ -1128,7 +1125,7 @@ X_ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m) * Pullup packet header if needed before storing it, * as other references may modify it in the meantime. */ - if (mb0 && (M_HASCL(mb0) || mb0->m_len < sizeof(struct ip6_hdr))) + if (mb0 && (!M_WRITABLE(mb0) || mb0->m_len < sizeof(struct ip6_hdr))) mb0 = m_pullup(mb0, sizeof(struct ip6_hdr)); if (mb0 == NULL) { free(rte, M_MRTABLE6); @@ -1397,7 +1394,7 @@ ip6_mdq(struct mbuf *m, struct ifnet *ifp, struct mf6c *rt) mm = m_copy(m, 0, sizeof(struct ip6_hdr)); if (mm && - (M_HASCL(mm) || + (!M_WRITABLE(mm) || mm->m_len < sizeof(struct ip6_hdr))) mm = m_pullup(mm, sizeof(struct ip6_hdr)); if (mm == NULL) @@ -1527,7 +1524,7 @@ phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m) */ mb_copy = m_copy(m, 0, M_COPYALL); if (mb_copy && - (M_HASCL(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr))) + (!M_WRITABLE(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr))) mb_copy = m_pullup(mb_copy, sizeof(struct ip6_hdr)); if (mb_copy == NULL) { return; |
