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| author | bz <bz@FreeBSD.org> | 2010-12-31 21:47:11 +0000 |
|---|---|---|
| committer | bz <bz@FreeBSD.org> | 2010-12-31 21:47:11 +0000 |
| commit | 969f8f9046a3a302dba8bdcd2c6d1c8d8785881b (patch) | |
| tree | aa19e49a2900d611041b3a5d33a25981187e4c85 /sys/netinet | |
| parent | 2a04b52e8a1dac2486826b340198915f0318482d (diff) | |
| download | FreeBSD-src-969f8f9046a3a302dba8bdcd2c6d1c8d8785881b.zip FreeBSD-src-969f8f9046a3a302dba8bdcd2c6d1c8d8785881b.tar.gz | |
Try to catch a possible divide-by-zero as early as possible if "mtu" is 0
(also test for negative MTUs if checking it anyway).
An MTU of 0 is arguably a bug elsewhere, but this at least gives us some
more debugging hints.
Sponsored by: ISPsystem (Early 2010)
MFC after: 1 week
Diffstat (limited to 'sys/netinet')
| -rw-r--r-- | sys/netinet/ip_output.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c index e292b60..3e592c5 100644 --- a/sys/netinet/ip_output.c +++ b/sys/netinet/ip_output.c @@ -323,6 +323,9 @@ again: } else { mtu = ifp->if_mtu; } + /* Catch a possible divide by zero later. */ + KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p", + __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp)); if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { m->m_flags |= M_MCAST; /* |
