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| author |   Jason A. Donenfeld <Jason@zx2c4.com> | 2018-04-14 05:27:19 +0200 |
|---|---|---|
| committer | Jason A. Donenfeld <Jason@zx2c4.com> | 2018-04-15 15:45:13 +0200 |
| commit | a1525bfdccc7fabf35c6c538409e4de4c4812169 (patch) | |
| tree | 81427f89c2bbf51aef4cde1e873c66a509851c28 /src/send.c | |
| parent | wg-quick: account for specified fwmark in auto routing mode (diff) | |
| download | wireguard-monolithic-historical-a1525bfdccc7fabf35c6c538409e4de4c4812169.tar.xz wireguard-monolithic-historical-a1525bfdccc7fabf35c6c538409e4de4c4812169.zip | |
send: account for route-based MTU
It might be that a particular route has a different MTU than the
interface, via `ip route add ... dev wg0 mtu 1281`, for example. In this
case, it's important that we don't accidently pad beyond the end of the
MTU. We accomplish that in this patch by carrying forward the MTU from
the dst if it exists. We also add a unit test for this issue.
Reported-by: Roman Mamedov <rm.wg@romanrm.net>
Diffstat (limited to 'src/send.c')
| -rw-r--r-- | src/send.c | 7 |
1 files changed, 4 insertions, 3 deletions
@@ -116,11 +116,11 @@ static inline unsigned int skb_padding(struct sk_buff *skb) * isn't strictly neccessary, but it's better to be cautious here, especially * if that code ever changes. */ - unsigned int last_unit = skb->len % skb->dev->mtu; + unsigned int last_unit = skb->len % PACKET_CB(skb)->mtu; unsigned int padded_size = (last_unit + MESSAGE_PADDING_MULTIPLE - 1) & ~(MESSAGE_PADDING_MULTIPLE - 1); - if (padded_size > skb->dev->mtu) - padded_size = skb->dev->mtu; + if (padded_size > PACKET_CB(skb)->mtu) + padded_size = PACKET_CB(skb)->mtu; return padded_size - last_unit; } @@ -178,6 +178,7 @@ void packet_send_keepalive(struct wireguard_peer *peer) return; skb_reserve(skb, DATA_PACKET_HEAD_ROOM); skb->dev = peer->device->dev; + PACKET_CB(skb)->mtu = skb->dev->mtu; skb_queue_tail(&peer->staged_packet_queue, skb); net_dbg_ratelimited("%s: Sending keepalive packet to peer %llu (%pISpfsc)\n", peer->device->dev->name, peer->internal_id, &peer->endpoint.addr); } |