kernel/linux.git/include/net/dst_metadata.h, branch v6.11.8

ip_tunnel: convert __be16 tunnel flags to bitmaps

2024-04-01T09:49:28+00:00

Historically, tunnel flags like TUNNEL_CSUM or TUNNEL_ERSPAN_OPT have been defined as __be16. Now all of those 16 bits are occupied and there's no more free space for new flags. It can't be simply switched to a bigger container with no adjustments to the values, since it's an explicit Endian storage, and on LE systems (__be16)0x0001 equals to (__be64)0x0001000000000000. We could probably define new 64-bit flags depending on the Endianness, i.e. (__be64)0x0001 on BE and (__be64)0x00010000... on LE, but that would introduce an Endianness dependency and spawn a ton of Sparse warnings. To mitigate them, all of those places which were adjusted with this change would be touched anyway, so why not define stuff properly if there's no choice. Define IP_TUNNEL_*_BIT counterparts as a bit number instead of the value already coded and a fistful of <16 <-> bitmap> converters and helpers. The two flags which have a different bit position are SIT_ISATAP_BIT and VTI_ISVTI_BIT, as they were defined not as __cpu_to_be16(), but as (__force __be16), i.e. had different positions on LE and BE. Now they both have strongly defined places. Change all __be16 fields which were used to store those flags, to IP_TUNNEL_DECLARE_FLAGS() -> DECLARE_BITMAP(__IP_TUNNEL_FLAG_NUM) -> unsigned long[1] for now, and replace all TUNNEL_* occurrences to their bitmap counterparts. Use the converters in the places which talk to the userspace, hardware (NFP) or other hosts (GRE header). The rest must explicitly use the new flags only. This must be done at once, otherwise there will be too many conversions throughout the code in the intermediate commits. Finally, disable the old __be16 flags for use in the kernel code (except for the two 'irregular' flags mentioned above), to prevent any accidental (mis)use of them. For the userspace, nothing is changed, only additions were made. Most noticeable bloat-o-meter difference (.text): vmlinux: 307/-1 (306) gre.ko: 62/0 (62) ip_gre.ko: 941/-217 (724) [*] ip_tunnel.ko: 390/-900 (-510) [**] ip_vti.ko: 138/0 (138) ip6_gre.ko: 534/-18 (516) [*] ip6_tunnel.ko: 118/-10 (108) [*] gre_flags_to_tnl_flags() grew, but still is inlined [**] ip_tunnel_find() got uninlined, hence such decrease The average code size increase in non-extreme case is 100-200 bytes per module, mostly due to sizeof(long) > sizeof(__be16), as %__IP_TUNNEL_FLAG_NUM is less than %BITS_PER_LONG and the compilers are able to expand the majority of bitmap_*() calls here into direct operations on scalars. Reviewed-by: Simon Horman Signed-off-by: Alexander Lobakin Signed-off-by: David S. Miller

xfrm: interface: Add unstable helpers for setting/getting XFRM metadata from TC-BPF

2022-12-06T05:58:27+00:00

This change adds xfrm metadata helpers using the unstable kfunc call interface for the TC-BPF hooks. This allows steering traffic towards different IPsec connections based on logic implemented in bpf programs. This object is built based on the availability of BTF debug info. When setting the xfrm metadata, percpu metadata dsts are used in order to avoid allocating a metadata dst per packet. In order to guarantee safe module unload, the percpu dsts are allocated on first use and never freed. The percpu pointer is stored in net/core/filter.c so that it can be reused on module reload. The metadata percpu dsts take ownership of the original skb dsts so that they may be used as part of the xfrm transmission logic - e.g. for MTU calculations. Signed-off-by: Eyal Birger Link: https://lore.kernel.org/r/20221203084659.1837829-3-eyal.birger@gmail.com Signed-off-by: Martin KaFai Lau

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

2022-10-03T06:52:13+00:00

Steffen Klassert says: ==================== 1) Refactor selftests to use an array of structs in xfrm_fill_key(). From Gautam Menghani. 2) Drop an unused argument from xfrm_policy_match. From Hongbin Wang. 3) Support collect metadata mode for xfrm interfaces. From Eyal Birger. 4) Add netlink extack support to xfrm. From Sabrina Dubroca. Please note, there is a merge conflict in: include/net/dst_metadata.h between commit: 0a28bfd4971f ("net/macsec: Add MACsec skb_metadata_dst Tx Data path support") from the net-next tree and commit: 5182a5d48c3d ("net: allow storing xfrm interface metadata in metadata_dst") from the ipsec-next tree. Can be solved as done in linux-next. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller

net/macsec: Add MACsec skb_metadata_dst Tx Data path support

2022-09-07T13:02:08+00:00

In the current MACsec offload implementation, MACsec interfaces shares the same MAC address by default. Therefore, HW can't distinguish from which MACsec interface the traffic originated from. MACsec stack will use skb_metadata_dst to store the SCI value, which is unique per Macsec interface, skb_metadat_dst will be used by the offloading device driver to associate the SKB with the corresponding offloaded interface (SCI). Signed-off-by: Lior Nahmanson Reviewed-by: Raed Salem Signed-off-by: Saeed Mahameed Signed-off-by: David S. Miller

xfrm: lwtunnel: add lwtunnel support for xfrm interfaces in collect_md mode

2022-08-29T08:44:08+00:00

Allow specifying the xfrm interface if_id and link as part of a route metadata using the lwtunnel infrastructure. This allows for example using a single xfrm interface in collect_md mode as the target of multiple routes each specifying a different if_id. With the appropriate changes to iproute2, considering an xfrm device ipsec1 in collect_md mode one can for example add a route specifying an if_id like so: ip route add dev ipsec1 encap xfrm if_id 1 In which case traffic routed to the device via this route would use if_id in the xfrm interface policy lookup. Or in the context of vrf, one can also specify the "link" property: ip route add dev ipsec1 encap xfrm if_id 1 link_dev eth15 Note: LWT_XFRM_LINK uses NLA_U32 similar to IFLA_XFRM_LINK even though internally "link" is signed. This is consistent with other _LINK attributes in other devices as well as in bpf and should not have an effect as device indexes can't be negative. Reviewed-by: Nicolas Dichtel Reviewed-by: Nikolay Aleksandrov Signed-off-by: Eyal Birger Signed-off-by: Steffen Klassert

net: allow storing xfrm interface metadata in metadata_dst

2022-08-29T08:38:19+00:00

XFRM interfaces provide the association of various XFRM transformations to a netdevice using an 'if_id' identifier common to both the XFRM data structures (polcies, states) and the interface. The if_id is configured by the controlling entity (usually the IKE daemon) and can be used by the administrator to define logical relations between different connections. For example, different connections can share the if_id identifier so that they pass through the same interface, . However, currently it is not possible for connections using a different if_id to use the same interface while retaining the logical separation between them, without using additional criteria such as skb marks or different traffic selectors. When having a large number of connections, it is useful to have a the logical separation offered by the if_id identifier but use a single network interface. Similar to the way collect_md mode is used in IP tunnels. This patch attempts to enable different configuration mechanisms - such as ebpf programs, LWT encapsulations, and TC - to attach metadata to skbs which would carry the if_id. This way a single xfrm interface in collect_md mode can demux traffic based on this configuration on tx and provide this metadata on rx. The XFRM metadata is somewhat similar to ip tunnel metadata in that it has an "id", and shares similar configuration entities (bpf, tc, ...), however, it does not necessarily represent an IP tunnel or use other ip tunnel information, and also has an optional "link" property which can be used for affecting underlying routing decisions. Additional xfrm related criteria may also be added in the future. Therefore, a new metadata type is introduced, to be used in subsequent patches in the xfrm interface and configuration entities. Reviewed-by: Nikolay Aleksandrov Reviewed-by: Nicolas Dichtel Signed-off-by: Eyal Birger Signed-off-by: Steffen Klassert

net: fix a memleak when uncloning an skb dst and its metadata

2022-02-09T11:41:47+00:00

When uncloning an skb dst and its associated metadata, a new dst+metadata is allocated and later replaces the old one in the skb. This is helpful to have a non-shared dst+metadata attached to a specific skb. The issue is the uncloned dst+metadata is initialized with a refcount of 1, which is increased to 2 before attaching it to the skb. When tun_dst_unclone returns, the dst+metadata is only referenced from a single place (the skb) while its refcount is 2. Its refcount will never drop to 0 (when the skb is consumed), leading to a memory leak. Fix this by removing the call to dst_hold in tun_dst_unclone, as the dst+metadata refcount is already 1. Fixes: fc4099f17240 ("openvswitch: Fix egress tunnel info.") Cc: Pravin B Shelar Reported-by: Vlad Buslov Tested-by: Vlad Buslov Signed-off-by: Antoine Tenart Signed-off-by: David S. Miller

net: do not keep the dst cache when uncloning an skb dst and its metadata

2022-02-09T11:41:47+00:00

When uncloning an skb dst and its associated metadata a new dst+metadata is allocated and the tunnel information from the old metadata is copied over there. The issue is the tunnel metadata has references to cached dst, which are copied along the way. When a dst+metadata refcount drops to 0 the metadata is freed including the cached dst entries. As they are also referenced in the initial dst+metadata, this ends up in UaFs. In practice the above did not happen because of another issue, the dst+metadata was never freed because its refcount never dropped to 0 (this will be fixed in a subsequent patch). Fix this by initializing the dst cache after copying the tunnel information from the old metadata to also unshare the dst cache. Fixes: d71785ffc7e7 ("net: add dst_cache to ovs vxlan lwtunnel") Cc: Paolo Abeni Reported-by: Vlad Buslov Tested-by: Vlad Buslov Signed-off-by: Antoine Tenart Acked-by: Paolo Abeni Signed-off-by: David S. Miller

net: validate lwtstate->data before returning from skb_tunnel_info()

2021-07-09T20:55:53+00:00

skb_tunnel_info() returns pointer of lwtstate->data as ip_tunnel_info type without validation. lwtstate->data can have various types such as mpls_iptunnel_encap, etc and these are not compatible. So skb_tunnel_info() should validate before returning that pointer. Splat looks like: BUG: KASAN: slab-out-of-bounds in vxlan_get_route+0x418/0x4b0 [vxlan] Read of size 2 at addr ffff888106ec2698 by task ping/811 CPU: 1 PID: 811 Comm: ping Not tainted 5.13.0+ #1195 Call Trace: dump_stack_lvl+0x56/0x7b print_address_description.constprop.8.cold.13+0x13/0x2ee ? vxlan_get_route+0x418/0x4b0 [vxlan] ? vxlan_get_route+0x418/0x4b0 [vxlan] kasan_report.cold.14+0x83/0xdf ? vxlan_get_route+0x418/0x4b0 [vxlan] vxlan_get_route+0x418/0x4b0 [vxlan] [ ... ] vxlan_xmit_one+0x148b/0x32b0 [vxlan] [ ... ] vxlan_xmit+0x25c5/0x4780 [vxlan] [ ... ] dev_hard_start_xmit+0x1ae/0x6e0 __dev_queue_xmit+0x1f39/0x31a0 [ ... ] neigh_xmit+0x2f9/0x940 mpls_xmit+0x911/0x1600 [mpls_iptunnel] lwtunnel_xmit+0x18f/0x450 ip_finish_output2+0x867/0x2040 [ ... ] Fixes: 61adedf3e3f1 ("route: move lwtunnel state to dst_entry") Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-04T00:26:51+00:00

Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller