fix KASSERT() for MHLEN case in m_defrag() - network stack usually does

m_adj(ETHER_ALIGN) so check that the mbuf chain data fits
M_LEADINGSPACE() + M_TRAILINGSPACE()
This commit is contained in:
jdolecek 2020-05-05 20:36:48 +00:00
parent b3f22be23a
commit 5eefcf3158

View File

@ -1,4 +1,4 @@
/* $NetBSD: uipc_mbuf.c,v 1.240 2020/04/25 11:03:04 jdolecek Exp $ */
/* $NetBSD: uipc_mbuf.c,v 1.241 2020/05/05 20:36:48 jdolecek Exp $ */
/*
* Copyright (c) 1999, 2001, 2018 The NetBSD Foundation, Inc.
@ -62,7 +62,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.240 2020/04/25 11:03:04 jdolecek Exp $");
__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.241 2020/05/05 20:36:48 jdolecek Exp $");
#ifdef _KERNEL_OPT
#include "opt_mbuftrace.h"
@ -1680,10 +1680,21 @@ m_defrag(struct mbuf *m, int how)
if ((m->m_flags & M_EXT) == 0 && m->m_pkthdr.len <= MCLBYTES) {
if (m->m_pkthdr.len <= MHLEN) {
if (M_TRAILINGSPACE(m) < (m->m_pkthdr.len - m->m_len)) {
KASSERT(M_LEADINGSPACE(m) >=
(m->m_pkthdr.len - m->m_len));
KASSERTMSG(M_LEADINGSPACE(m) +
M_TRAILINGSPACE(m) >=
(m->m_pkthdr.len - m->m_len),
"too small leading %d trailing %d ro? %d"
" pkthdr.len %d mlen %d",
(int)M_LEADINGSPACE(m),
(int)M_TRAILINGSPACE(m),
M_READONLY(m),
m->m_pkthdr.len, m->m_len);
memmove(m->m_pktdat, m->m_data, m->m_len);
m->m_data = m->m_pktdat;
KASSERT(M_TRAILINGSPACE(m) >=
(m->m_pkthdr.len - m->m_len));
}
} else {
/* Must copy data before adding cluster */