diff options
| author | Dmitry Safonov <dima@arista.com> | 2025-10-09 18:02:19 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-10-23 17:16:31 +0300 |
| commit | 48294a67863c9cfa367abb66bbf0ef6548ae124f (patch) | |
| tree | ec3b517b00a5dc4e963d6b27595ca2108187c229 /net/ipv4 | |
| parent | 932f7cd27905f1ddac6c4b38e90fa1e58c2a59d9 (diff) | |
| download | linux-48294a67863c9cfa367abb66bbf0ef6548ae124f.tar.xz | |
net/ip6_tunnel: Prevent perpetual tunnel growth
[ Upstream commit 21f4d45eba0b2dcae5dbc9e5e0ad08735c993f16 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/ip_tunnel.c | 14 |
1 files changed, 0 insertions, 14 deletions
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index b5d64cd3ab0a..090403c8cc6c 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -567,20 +567,6 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, return 0; } -static void ip_tunnel_adj_headroom(struct net_device *dev, unsigned int headroom) -{ - /* we must cap headroom to some upperlimit, else pskb_expand_head - * will overflow header offsets in skb_headers_offset_update(). - */ - static const unsigned int max_allowed = 512; - - if (headroom > max_allowed) - headroom = max_allowed; - - if (headroom > READ_ONCE(dev->needed_headroom)) - WRITE_ONCE(dev->needed_headroom, headroom); -} - void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto, int tunnel_hlen) { |