aboutsummaryrefslogtreecommitdiff
path: root/networking/udhcp/arpping.c
diff options
context:
space:
mode:
authorGlenn L McGrath <bug1@ihug.co.nz>2004-03-05 14:25:49 +0000
committerGlenn L McGrath <bug1@ihug.co.nz>2004-03-05 14:25:49 +0000
commit3f79300e37d02b1d5df4de97089e89927d1063a2 (patch)
tree2d868bbb6059ee64dbf5cd6af9879a33c31562f8 /networking/udhcp/arpping.c
parent0226596dcb218349238380638c46ae1009eb82d3 (diff)
downloadbusybox-3f79300e37d02b1d5df4de97089e89927d1063a2.tar.gz
Patch by Andrew Victor,
In arpping.h, fix structure alignment of "struct arpMsg". GCC can insert padding in the structure which causes udhcpd to send an invalid ARP packet on the network. It will then not receive a valid reply, which can cause it to assign an IP address that's already in use on the network. (With kernels before 2.4.20, the "struct ethhdr" in linux/if_ether.h wasn't marked as packed. This is also an issue if your toolchain was built with a pre-2.4.20 kernel).
Diffstat (limited to 'networking/udhcp/arpping.c')
-rw-r--r--networking/udhcp/arpping.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/networking/udhcp/arpping.c b/networking/udhcp/arpping.c
index f2e3768c5..23c7d46b3 100644
--- a/networking/udhcp/arpping.c
+++ b/networking/udhcp/arpping.c
@@ -60,9 +60,9 @@ int arpping(uint32_t yiaddr, uint32_t ip, uint8_t *mac, char *interface)
/* send arp request */
memset(&arp, 0, sizeof(arp));
- memcpy(arp.ethhdr.h_dest, MAC_BCAST_ADDR, 6); /* MAC DA */
- memcpy(arp.ethhdr.h_source, mac, 6); /* MAC SA */
- arp.ethhdr.h_proto = htons(ETH_P_ARP); /* protocol type (Ethernet) */
+ memcpy(arp.h_dest, MAC_BCAST_ADDR, 6); /* MAC DA */
+ memcpy(arp.h_source, mac, 6); /* MAC SA */
+ arp.h_proto = htons(ETH_P_ARP); /* protocol type (Ethernet) */
arp.htype = htons(ARPHRD_ETHER); /* hardware type */
arp.ptype = htons(ETH_P_IP); /* protocol type (ARP message) */
arp.hlen = 6; /* hardware address length */