slirp/arp: do not special-case bogus IP addresses
Do not special-case addresses with zero host part, as we do not
necessarily know how big it is, and the guest can fake them anyway.
Silently avoid having 0.0.0.0 as a destination, however.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
[Edgar: Minor change to subject]
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
diff --git a/arp_table.c b/arp_table.c
index b0f7081..cabd87e 100644
--- a/arp_table.c
+++ b/arp_table.c
@@ -36,12 +36,7 @@
DEBUG_ARGS((dfd, " hw addr = %02x:%02x:%02x:%02x:%02x:%02x\n", ethaddr[0],
ethaddr[1], ethaddr[2], ethaddr[3], ethaddr[4], ethaddr[5]));
- /* Check 0.0.0.0/8 invalid source-only addresses */
- if ((ip_addr & htonl(~(0xfU << 28))) == 0) {
- return;
- }
-
- if (ip_addr == 0xffffffff || ip_addr == broadcast_addr) {
+ if (ip_addr == 0 || ip_addr == 0xffffffff || ip_addr == broadcast_addr) {
/* Do not register broadcast addresses */
return;
}
@@ -72,9 +67,6 @@
DEBUG_CALL("arp_table_search");
DEBUG_ARG("ip = 0x%x", ip_addr);
- /* Check 0.0.0.0/8 invalid source-only addresses */
- assert((ip_addr & htonl(~(0xfU << 28))) != 0);
-
/* If broadcast address */
if (ip_addr == 0xffffffff || ip_addr == broadcast_addr) {
/* return Ethernet broadcast address */
diff --git a/slirp.c b/slirp.c
index f002b0a..0a143da 100644
--- a/slirp.c
+++ b/slirp.c
@@ -772,6 +772,11 @@
return 1;
}
+ if (iph->ip_dst.s_addr == 0) {
+ /* 0.0.0.0 can not be a destination address, something went wrong,
+ * avoid making it worse */
+ return 1;
+ }
if (!arp_table_search(slirp, iph->ip_dst.s_addr, ethaddr)) {
uint8_t arp_req[ETH_HLEN + sizeof(struct arphdr)];
struct ethhdr *reh = (struct ethhdr *)arp_req;
