path: root/iptables
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authorFlorian Westphal <>2019-02-22 13:26:05 +0100
committerFlorian Westphal <>2019-02-22 16:50:14 +0100
commitd68672a641439b72bccfcb39d50f26fe3f915c19 (patch)
tree128af8af28fd18116bd6283483e85352339b609f /iptables
parent73a0c2ef36d15e8277f0e00337736668b325381a (diff)
arptables-nft: fix decoding of hlen on bigendian platforms
The existing test fail with: extensions/libarpt_standard.t: ERROR: line 2 (cannot find: arptables -I INPUT -s ... 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 <> Acked-by: Phil Sutter <>
Diffstat (limited to 'iptables')
1 files changed, 3 insertions, 2 deletions
diff --git a/iptables/nft-arp.c b/iptables/nft-arp.c
index a3715579..9805bbe0 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;
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)