[NETFILTER] arp_tables: Fix unaligned accesses.
There are two device string comparison loops in arp_packet_match().
The first one goes byte-by-byte but the second one tries to be
clever and cast the string to a long and compare by longs.
The device name strings in the arp table entries are not guarenteed
to be aligned enough to make this value, so just use byte-by-byte
for both cases.
Based upon a report by <drraid@gmail.com>.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 5170f5c..57b0221 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -166,13 +166,9 @@
return 0;
}
- for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
- unsigned long odev;
- memcpy(&odev, outdev + i*sizeof(unsigned long),
- sizeof(unsigned long));
- ret |= (odev
- ^ ((const unsigned long *)arpinfo->outiface)[i])
- & ((const unsigned long *)arpinfo->outiface_mask)[i];
+ for (i = 0, ret = 0; i < IFNAMSIZ; i++) {
+ ret |= (outdev[i] ^ arpinfo->outiface[i])
+ & arpinfo->outiface_mask[i];
}
if (FWINV(ret != 0, ARPT_INV_VIA_OUT)) {