The existing test fail with:
extensions/libarpt_standard.t: ERROR: line 2 (cannot find: arptables -I INPUT -s 192.168.0.1)
... because hlen is 0 instead of expected "6".
The rule is correct, i.e. this is a decode/display bug: arp_hlen is
specified as 'unsigned short' instead of uint8_t.
On LSB systems, this doesn't matter but on MSB the value then is '0x600'
instead of '0x006' which becomes 0 when assignment to the u8 header field.
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
iptables/nft-arp.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/iptables/nft-arp.c b/iptables/nft-arp.c
index 637da4274ded..c786abb82ed2 100644
--- a/iptables/nft-arp.c
+++ b/iptables/nft-arp.c
@@ -338,7 +338,8 @@ static void nft_arp_parse_payload(struct nft_xt_ctx *ctx,
struct iptables_command_state *cs = data;
struct arpt_entry *fw = &cs->arp;
struct in_addr addr;
- unsigned short int ar_hrd, ar_pro, ar_op, ar_hln;
+ uint16_t ar_hrd, ar_pro, ar_op;
+ uint8_t ar_hln;
bool inv;
switch (ctx->payload.offset) {
@@ -364,7 +365,7 @@ static void nft_arp_parse_payload(struct nft_xt_ctx *ctx,
fw->arp.invflags |= ARPT_INV_ARPOP;
break;
case offsetof(struct arphdr, ar_hln):
- get_cmp_data(e, &ar_hln, sizeof(ar_op), &inv);
+ get_cmp_data(e, &ar_hln, sizeof(ar_hln), &inv);
fw->arp.arhln = ar_hln;
fw->arp.arhln_mask = 0xff;
if (inv)
--
2.19.2
