kernel/linux.git/net/ipv4/ip_tunnel.c, branch v6.12.80

net/ip6_tunnel: Prevent perpetual tunnel growth

2025-10-23T14:20:29+00:00

[ 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 Cc: Francesco Ruggeri Signed-off-by: Dmitry Safonov Link: https://patch.msgid.link/20251009-ip6_tunnel-headroom-v2-1-8e4dbd8f7e35@arista.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: Fix netns for ip_tunnel_init_flow()

2025-01-09T12:33:38+00:00

[ Upstream commit b5a7b661a073727219fedc35f5619f62418ffe72 ] The device denoted by tunnel->parms.link resides in the underlay net namespace. Therefore pass tunnel->net to ip_tunnel_init_flow(). Fixes: db53cd3d88dc ("net: Handle l3mdev in ip_tunnel_init_flow") Signed-off-by: Xiao Liang Reviewed-by: Ido Schimmel Link: https://patch.msgid.link/20241219130336.103839-1-shaw.leon@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: ip_tunnel: Fix suspicious RCU usage warning in ip_tunnel_find()

2024-10-29T18:12:53+00:00

The per-netns IP tunnel hash table is protected by the RTNL mutex and ip_tunnel_find() is only called from the control path where the mutex is taken. Add a lockdep expression to hlist_for_each_entry_rcu() in ip_tunnel_find() in order to validate that the mutex is held and to silence the suspicious RCU usage warning [1]. [1] WARNING: suspicious RCU usage 6.12.0-rc3-custom-gd95d9a31aceb #139 Not tainted ----------------------------- net/ipv4/ip_tunnel.c:221 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/362: #0: ffffffff86fc7cb0 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x377/0xf60 stack backtrace: CPU: 12 UID: 0 PID: 362 Comm: ip Not tainted 6.12.0-rc3-custom-gd95d9a31aceb #139 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: dump_stack_lvl+0xba/0x110 lockdep_rcu_suspicious.cold+0x4f/0xd6 ip_tunnel_find+0x435/0x4d0 ip_tunnel_newlink+0x517/0x7a0 ipgre_newlink+0x14c/0x170 __rtnl_newlink+0x1173/0x19c0 rtnl_newlink+0x6c/0xa0 rtnetlink_rcv_msg+0x3cc/0xf60 netlink_rcv_skb+0x171/0x450 netlink_unicast+0x539/0x7f0 netlink_sendmsg+0x8c1/0xd80 ____sys_sendmsg+0x8f9/0xc20 ___sys_sendmsg+0x197/0x1e0 __sys_sendmsg+0x122/0x1f0 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Suggested-by: Eric Dumazet Signed-off-by: Ido Schimmel Reviewed-by: Eric Dumazet Link: https://patch.msgid.link/20241023123009.749764-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski

ipv4: ip_tunnel: Unmask upper DSCP bits in ip_tunnel_xmit()

2024-09-09T13:14:53+00:00

Unmask the upper DSCP bits when initializing an IPv4 flow key via ip_tunnel_init_flow() before passing it to ip_route_output_key() so that in the future we could perform the FIB lookup according to the full DSCP value. Note that the 'tos' variable includes the full DS field. Either the one specified as part of the tunnel parameters or the one inherited from the inner packet. Signed-off-by: Ido Schimmel Reviewed-by: Guillaume Nault Signed-off-by: David S. Miller

ipv4: ip_tunnel: Unmask upper DSCP bits in ip_md_tunnel_xmit()

2024-09-09T13:14:53+00:00

Unmask the upper DSCP bits when initializing an IPv4 flow key via ip_tunnel_init_flow() before passing it to ip_route_output_key() so that in the future we could perform the FIB lookup according to the full DSCP value. Note that the 'tos' variable includes the full DS field. Either the one specified via the tunnel key or the one inherited from the inner packet. Signed-off-by: Ido Schimmel Reviewed-by: Guillaume Nault Signed-off-by: David S. Miller

ipv4: ip_tunnel: Unmask upper DSCP bits in ip_tunnel_bind_dev()

2024-09-09T13:14:53+00:00

netdev_features: convert NETIF_F_NETNS_LOCAL to dev->netns_local

2024-09-03T09:36:43+00:00

"Interface can't change network namespaces" is rather an attribute, not a feature, and it can't be changed via Ethtool. Make it a "cold" private flag instead of a netdev_feature and free one more bit. Signed-off-by: Alexander Lobakin Signed-off-by: Paolo Abeni

net/ipv4: net: prefer strscpy over strcpy

2024-08-29T19:33:14+00:00

The deprecated helper strcpy() performs no bounds checking on the destination buffer. This could result in linear overflows beyond the end of the buffer, leading to all kinds of misbehaviors. The safe replacement is strscpy() [1]. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1] Signed-off-by: Hongbo Li Link: https://patch.msgid.link/20240828123224.3697672-7-lihongbo22@huawei.com Signed-off-by: Jakub Kicinski

ip_tunnel: Move stats allocation to core

2024-06-12T02:24:37+00:00

With commit 34d21de99cea9 ("net: Move {l,t,d}stats allocation to core and convert veth & vrf"), stats allocation could be done on net core instead of this driver. With this new approach, the driver doesn't have to bother with error handling (allocation failure checking, making sure free happens in the right spot, etc). This is core responsibility now. Move ip_tunnel driver to leverage the core allocation. All the ip_tunnel_init() users call ip_tunnel_init() as part of their .ndo_init callback. The .ndo_init callback is called before the stats allocation in netdev_register(), thus, the allocation will happen before the netdev is visible. Signed-off-by: Breno Leitao Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20240607084420.3932875-1-leitao@debian.org Signed-off-by: Jakub Kicinski

net: annotate writes on dev->mtu from ndo_change_mtu()

2024-05-07T23:19:14+00:00

Simon reported that ndo_change_mtu() methods were never updated to use WRITE_ONCE(dev->mtu, new_mtu) as hinted in commit 501a90c94510 ("inet: protect against too small mtu values.") We read dev->mtu without holding RTNL in many places, with READ_ONCE() annotations. It is time to take care of ndo_change_mtu() methods to use corresponding WRITE_ONCE() Signed-off-by: Eric Dumazet Reported-by: Simon Horman Closes: https://lore.kernel.org/netdev/20240505144608.GB67882@kernel.org/ Reviewed-by: Jacob Keller Reviewed-by: Sabrina Dubroca Reviewed-by: Simon Horman Acked-by: Shannon Nelson Link: https://lore.kernel.org/r/20240506102812.3025432-1-edumazet@google.com Signed-off-by: Jakub Kicinski