diff options
| author | Dmitry Safonov <dima@arista.com> | 2025-10-09 16:02:19 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-10-13 17:43:46 -0700 |
| commit | 21f4d45eba0b2dcae5dbc9e5e0ad08735c993f16 (patch) | |
| tree | 4a5d6d392dd03d693a87eae2438bcde385dfc552 /net/ipv6 | |
| parent | e4d0c909bf8328d986bf3aadba0c33a72b5ae30d (diff) | |
net/ip6_tunnel: Prevent perpetual tunnel growth
Similarly to ipv4 tunnel, ipv6 version updates dev->needed_headroom, too.
While ipv4 tunnel headroom adjustment growth was limited in
commit 5ae1e9922bbd ("net: ip_tunnel: prevent perpetual headroom growth"),
ipv6 tunnel yet increases the headroom without any ceiling.
Reflect ipv4 tunnel headroom adjustment limit on ipv6 version.
Credits to Francesco Ruggeri, who was originally debugging this issue
and wrote local Arista-specific patch and a reproducer.
Fixes: 8eb30be0352d ("ipv6: Create ip6_tnl_xmit")
Cc: Florian Westphal <fw@strlen.de>
Cc: Francesco Ruggeri <fruggeri05@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://patch.msgid.link/20251009-ip6_tunnel-headroom-v2-1-8e4dbd8f7e35@arista.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/ip6_tunnel.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index 3262e81223df..6405072050e0 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -1257,8 +1257,7 @@ route_lookup: */ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct ipv6hdr) + dst->header_len + t->hlen; - if (max_headroom > READ_ONCE(dev->needed_headroom)) - WRITE_ONCE(dev->needed_headroom, max_headroom); + ip_tunnel_adj_headroom(dev, max_headroom); err = ip6_tnl_encap(skb, t, &proto, fl6); if (err) |