Module Name: src
Committed By: roy
Date: Sat Feb 13 07:57:09 UTC 2021
Modified Files:
src/sys/net: if_arp.h
src/sys/netinet: if_arp.c
Log Message:
if_arp: Ensure that arphdr is aligned
To generate a diff of this commit:
cvs rdiff -u -r1.37 -r1.38 src/sys/net/if_arp.h
cvs rdiff -u -r1.298 -r1.299 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/net/if_arp.h
diff -u src/sys/net/if_arp.h:1.37 src/sys/net/if_arp.h:1.38
--- src/sys/net/if_arp.h:1.37 Wed Feb 3 18:13:13 2021
+++ src/sys/net/if_arp.h Sat Feb 13 07:57:09 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: if_arp.h,v 1.37 2021/02/03 18:13:13 roy Exp $ */
+/* $NetBSD: if_arp.h,v 1.38 2021/02/13 07:57:09 roy Exp $ */
/*
* Copyright (c) 1986, 1993
@@ -72,6 +72,11 @@ struct arphdr {
uint8_t ar_tpa[]; /* target protocol address */
#endif
};
+#ifdef __NO_STRICT_ALIGNMENT
+#define ARP_HDR_ALIGNED_P(ah) 1
+#else
+#define ARP_HDR_ALIGNED_P(ah) ((((vaddr_t) (ah)) & 3) == 0)
+#endif
#ifdef __CTASSERT
__CTASSERT(sizeof(struct arphdr) == 8);
#endif
Index: src/sys/netinet/if_arp.c
diff -u src/sys/netinet/if_arp.c:1.298 src/sys/netinet/if_arp.c:1.299
--- src/sys/netinet/if_arp.c:1.298 Tue Feb 2 10:48:33 2021
+++ src/sys/netinet/if_arp.c Sat Feb 13 07:57:09 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: if_arp.c,v 1.298 2021/02/02 10:48:33 yamt Exp $ */
+/* $NetBSD: if_arp.c,v 1.299 2021/02/13 07:57:09 roy 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 1.298 2021/02/02 10:48:33 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.299 2021/02/13 07:57:09 roy Exp $");
#ifdef _KERNEL_OPT
#include "opt_ddb.h"
@@ -700,9 +700,19 @@ arpintr(void)
MCLAIM(m, &arpdomain.dom_mowner);
ARP_STATINC(ARP_STAT_RCVTOTAL);
- arplen = sizeof(struct arphdr);
- if (m->m_len < arplen && (m = m_pullup(m, arplen)) == NULL)
- goto badlen;
+ /* If the ARP header is not aligned, slurp it up into a new
+ * mbuf with space for link headers, in the event we forward
+ * it. Otherwise, if it is aligned, make sure the entire
+ * base ARP header is in the first mbuf of the chain.
+ */
+ if (ARP_HDR_ALIGNED_P(mtod(m, void *)) == 0) {
+ if ((m = m_copyup(m, sizeof(*ar),
+ (max_linkhdr + 3) & ~3)) == NULL)
+ goto badlen;
+ } else if (__predict_false(m->m_len < sizeof(*ar))) {
+ if ((m = m_pullup(m, sizeof(*ar))) == NULL)
+ goto badlen;
+ }
ar = mtod(m, struct arphdr *);
rcvif = m_get_rcvif(m, &s);
