Module Name: src
Committed By: maxv
Date: Tue Feb 13 07:51:24 UTC 2018
Modified Files:
src/sys/netinet: if_arp.c
Log Message:
Fix three things in arpintr():
* mtod can't return NULL.
* It is wrong to kick the packet if m->m_len < arplen. While this check
always returns false for native Ethernet interfaces, it may not if the
frame is encapsulated in EtherIP/L2TP. Use m_pullup instead.
* Remove XXX, it is fine. Reduce the indentation level afterwards.
To generate a diff of this commit:
cvs rdiff -u -r1.257 -r1.258 src/sys/netinet/if_arp.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/netinet/if_arp.c
diff -u src/sys/netinet/if_arp.c:1.257 src/sys/netinet/if_arp.c:1.258
--- src/sys/netinet/if_arp.c:1.257 Tue Feb 13 07:44:25 2018
+++ src/sys/netinet/if_arp.c Tue Feb 13 07:51:24 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: if_arp.c,v 1.257 2018/02/13 07:44:25 maxv Exp $ */
+/* $NetBSD: if_arp.c,v 1.258 2018/02/13 07:51:24 maxv Exp $ */
/*
* Copyright (c) 1998, 2000, 2008 The NetBSD Foundation, Inc.
@@ -68,7 +68,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.257 2018/02/13 07:44:25 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.258 2018/02/13 07:51:24 maxv Exp $");
#ifdef _KERNEL_OPT
#include "opt_ddb.h"
@@ -939,12 +939,10 @@ arpintr(void)
MCLAIM(m, &arpdomain.dom_mowner);
ARP_STATINC(ARP_STAT_RCVTOTAL);
- /*
- * First, make sure we have at least struct arphdr.
- */
- if (m->m_len < sizeof(struct arphdr) ||
- (ar = mtod(m, struct arphdr *)) == NULL)
+ arplen = sizeof(struct arphdr);
+ if (m->m_len < arplen && (m = m_pullup(m, arplen)) == NULL)
goto badlen;
+ ar = mtod(m, struct arphdr *);
rcvif = m_get_rcvif(m, &s);
if (__predict_false(rcvif == NULL)) {
@@ -963,23 +961,26 @@ arpintr(void)
}
m_put_rcvif(rcvif, &s);
- if (/* XXX ntohs(ar->ar_hrd) == ARPHRD_ETHER && */
- m->m_len >= arplen)
- switch (ntohs(ar->ar_pro)) {
- case ETHERTYPE_IP:
- case ETHERTYPE_IPTRAILERS:
- in_arpinput(m);
- continue;
- default:
- ARP_STATINC(ARP_STAT_RCVBADPROTO);
- }
- else {
-badlen:
- ARP_STATINC(ARP_STAT_RCVBADLEN);
+ if (m->m_len < arplen && (m = m_pullup(m, arplen)) == NULL)
+ goto badlen;
+ ar = mtod(m, struct arphdr *);
+
+ switch (ntohs(ar->ar_pro)) {
+ case ETHERTYPE_IP:
+ case ETHERTYPE_IPTRAILERS:
+ in_arpinput(m);
+ continue;
+ default:
+ ARP_STATINC(ARP_STAT_RCVBADPROTO);
+ goto free;
}
+
+badlen:
+ ARP_STATINC(ARP_STAT_RCVBADLEN);
free:
m_freem(m);
}
+
out:
SOFTNET_KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
return; /* XXX gcc */
