From: Justin Pettit <jpettit@nicira.com>
Date: Thu, 3 Nov 2011 01:22:22 +0000 (-0700)
Subject: flow: Rearrange IPv6 addresses to remove potential hole in structure.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5145475f555867bf510428d65ced59369c7d8f4f;p=openvswitch

flow: Rearrange IPv6 addresses to remove potential hole in structure.

On some platforms, the in6_addr structure is made up of 16- or 32-bit
members.  Depending on the members of the "flow" structure, this can
lead to holes in the middle.  Moving the IPv6 addresses to the middle
fixes that on these platforms.
---

diff --git a/lib/flow.h b/lib/flow.h
index 0abfe5a4..ff440a23 100644
--- a/lib/flow.h
+++ b/lib/flow.h
@@ -54,6 +54,9 @@ BUILD_ASSERT_DECL(FLOW_FRAG_LATER == NX_IP_FRAG_LATER);
 
 struct flow {
     ovs_be64 tun_id;            /* Encapsulating tunnel ID. */
+    struct in6_addr ipv6_src;   /* IPv6 source address. */
+    struct in6_addr ipv6_dst;   /* IPv6 destination address. */
+    struct in6_addr nd_target;  /* IPv6 neighbor discovery (ND) target. */
     uint32_t priority;          /* Packet priority for QoS. */
     uint32_t regs[FLOW_N_REGS]; /* Registers. */
     ovs_be32 nw_src;            /* IPv4 source address. */
@@ -69,9 +72,6 @@ struct flow {
     uint8_t tos_frag;           /* IP ToS in top bits, FLOW_FRAG_* in low. */
     uint8_t arp_sha[6];         /* ARP/ND source hardware address. */
     uint8_t arp_tha[6];         /* ARP/ND target hardware address. */
-    struct in6_addr ipv6_src;   /* IPv6 source address. */
-    struct in6_addr ipv6_dst;   /* IPv6 destination address. */
-    struct in6_addr nd_target;  /* IPv6 neighbor discovery (ND) target. */
     uint32_t reserved;          /* Reserved for 64-bit packing. */
 };
 
@@ -79,8 +79,8 @@ struct flow {
  * flow", followed by FLOW_PAD_SIZE bytes of padding. */
 #define FLOW_SIG_SIZE (104 + FLOW_N_REGS * 4)
 #define FLOW_PAD_SIZE 4
-BUILD_ASSERT_DECL(offsetof(struct flow, nd_target) == FLOW_SIG_SIZE - 16);
-BUILD_ASSERT_DECL(sizeof(((struct flow *)0)->nd_target) == 16);
+BUILD_ASSERT_DECL(offsetof(struct flow, arp_tha) == FLOW_SIG_SIZE - 6);
+BUILD_ASSERT_DECL(sizeof(((struct flow *)0)->arp_tha) == 6);
 BUILD_ASSERT_DECL(sizeof(struct flow) == FLOW_SIG_SIZE + FLOW_PAD_SIZE);
 
 /* Remember to update FLOW_WC_SEQ when changing 'struct flow'. */