kernel/linux.git/net/openvswitch/flow.c, branch v5.10.257

net: openvswitch: Fix the dead loop of MPLS parse

2025-06-27T10:04:04+00:00

[ Upstream commit 0bdc924bfb319fb10d1113cbf091fc26fb7b1f99 ] The unexpected MPLS packet may not end with the bottom label stack. When there are many stacks, The label count value has wrapped around. A dead loop occurs, soft lockup/CPU stuck finally. stack backtrace: UBSAN: array-index-out-of-bounds in /build/linux-0Pa0xK/linux-5.15.0/net/openvswitch/flow.c:662:26 index -1 is out of range for type '__be32 [3]' CPU: 34 PID: 0 Comm: swapper/34 Kdump: loaded Tainted: G OE 5.15.0-121-generic #131-Ubuntu Hardware name: Dell Inc. PowerEdge C6420/0JP9TF, BIOS 2.12.2 07/14/2021 Call Trace: show_stack+0x52/0x5c dump_stack_lvl+0x4a/0x63 dump_stack+0x10/0x16 ubsan_epilogue+0x9/0x36 __ubsan_handle_out_of_bounds.cold+0x44/0x49 key_extract_l3l4+0x82a/0x840 [openvswitch] ? kfree_skbmem+0x52/0xa0 key_extract+0x9c/0x2b0 [openvswitch] ovs_flow_key_extract+0x124/0x350 [openvswitch] ovs_vport_receive+0x61/0xd0 [openvswitch] ? kernel_init_free_pages.part.0+0x4a/0x70 ? get_page_from_freelist+0x353/0x540 netdev_port_receive+0xc4/0x180 [openvswitch] ? netdev_port_receive+0x180/0x180 [openvswitch] netdev_frame_hook+0x1f/0x40 [openvswitch] __netif_receive_skb_core.constprop.0+0x23a/0xf00 __netif_receive_skb_list_core+0xfa/0x240 netif_receive_skb_list_internal+0x18e/0x2a0 napi_complete_done+0x7a/0x1c0 bnxt_poll+0x155/0x1c0 [bnxt_en] __napi_poll+0x30/0x180 net_rx_action+0x126/0x280 ? bnxt_msix+0x67/0x80 [bnxt_en] handle_softirqs+0xda/0x2d0 irq_exit_rcu+0x96/0xc0 common_interrupt+0x8e/0xa0 Fixes: fbdcdd78da7c ("Change in Openvswitch to support MPLS label depth of 3 in ingress direction") Signed-off-by: Faicker Mo Acked-by: Ilya Maximets Reviewed-by: Aaron Conole Link: https://patch.msgid.link/259D3404-575D-4A6D-B263-1DF59A67CF89@zenlayer.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: openvswitch: fix overwriting ct original tuple for ICMPv6

2024-06-16T11:32:09+00:00

[ Upstream commit 7c988176b6c16c516474f6fceebe0f055af5eb56 ] OVS_PACKET_CMD_EXECUTE has 3 main attributes: - OVS_PACKET_ATTR_KEY - Packet metadata in a netlink format. - OVS_PACKET_ATTR_PACKET - Binary packet content. - OVS_PACKET_ATTR_ACTIONS - Actions to execute on the packet. OVS_PACKET_ATTR_KEY is parsed first to populate sw_flow_key structure with the metadata like conntrack state, input port, recirculation id, etc. Then the packet itself gets parsed to populate the rest of the keys from the packet headers. Whenever the packet parsing code starts parsing the ICMPv6 header, it first zeroes out fields in the key corresponding to Neighbor Discovery information even if it is not an ND packet. It is an 'ipv6.nd' field. However, the 'ipv6' is a union that shares the space between 'nd' and 'ct_orig' that holds the original tuple conntrack metadata parsed from the OVS_PACKET_ATTR_KEY. ND packets should not normally have conntrack state, so it's fine to share the space, but normal ICMPv6 Echo packets or maybe other types of ICMPv6 can have the state attached and it should not be overwritten. The issue results in all but the last 4 bytes of the destination address being wiped from the original conntrack tuple leading to incorrect packet matching and potentially executing wrong actions in case this packet recirculates within the datapath or goes back to userspace. ND fields should not be accessed in non-ND packets, so not clearing them should be fine. Executing memset() only for actual ND packets to avoid the issue. Initializing the whole thing before parsing is needed because ND packet may not contain all the options. The issue only affects the OVS_PACKET_CMD_EXECUTE path and doesn't affect packets entering OVS datapath from network interfaces, because in this case CT metadata is populated from skb after the packet is already parsed. Fixes: 9dd7f8907c37 ("openvswitch: Add original direction conntrack tuple to sw_flow_key.") Reported-by: Antonin Bas Closes: https://github.com/openvswitch/ovs-issues/issues/327 Signed-off-by: Ilya Maximets Acked-by: Aaron Conole Acked-by: Eelco Chaudron Link: https://lore.kernel.org/r/20240509094228.1035477-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: openvswitch: fix parsing of nw_proto for IPv6 fragments

2022-06-29T06:59:45+00:00

commit 12378a5a75e33f34f8586706eb61cca9e6d4690c upstream. When a packet enters the OVS datapath and does not match any existing flows installed in the kernel flow cache, the packet will be sent to userspace to be parsed, and a new flow will be created. The kernel and OVS rely on each other to parse packet fields in the same way so that packets will be handled properly. As per the design document linked below, OVS expects all later IPv6 fragments to have nw_proto=44 in the flow key, so they can be correctly matched on OpenFlow rules. OpenFlow controllers create pipelines based on this design. This behavior was changed by the commit in the Fixes tag so that nw_proto equals the next_header field of the last extension header. However, there is no counterpart for this change in OVS userspace, meaning that this field is parsed differently between OVS and the kernel. This is a problem because OVS creates actions based on what is parsed in userspace, but the kernel-provided flow key is used as a match criteria, as described in Documentation/networking/openvswitch.rst. This leads to issues such as packets incorrectly matching on a flow and thus the wrong list of actions being applied to the packet. Such changes in packet parsing cannot be implemented without breaking the userspace. The offending commit is partially reverted to restore the expected behavior. The change technically made sense and there is a good reason that it was implemented, but it does not comply with the original design of OVS. If in the future someone wants to implement such a change, then it must be user-configurable and disabled by default to preserve backwards compatibility with existing OVS versions. Cc: stable@vger.kernel.org Fixes: fa642f08839b ("openvswitch: Derive IP protocol number for IPv6 later frags") Link: https://docs.openvswitch.org/en/latest/topics/design/#fragments Signed-off-by: Rosemarie O'Riorden Acked-by: Eelco Chaudron Link: https://lore.kernel.org/r/20220621204845.9721-1-roriorden@redhat.com Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

net/sched: act_ct: fix miss set mru for ovs after defrag in act_ct

2020-08-03T22:04:48+00:00

When openvswitch conntrack offload with act_ct action. Fragment packets defrag in the ingress tc act_ct action and miss the next chain. Then the packet pass to the openvswitch datapath without the mru. The over mtu packet will be dropped in output action in openvswitch for over mtu. "kernel: net2: dropped over-mtu packet: 1528 > 1500" This patch add mru in the tc_skb_ext for adefrag and miss next chain situation. And also add mru in the qdisc_skb_cb. The act_ct set the mru to the qdisc_skb_cb when the packet defrag. And When the chain miss, The mru is set to tc_skb_ext which can be got by ovs datapath. Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct") Signed-off-by: wenxu Reviewed-by: Cong Wang Signed-off-by: David S. Miller

Change in Openvswitch to support MPLS label depth of 3 in ingress direction

2019-11-06T02:02:29+00:00

The openvswitch was supporting a MPLS label depth of 1 in the ingress direction though the userspace OVS supports a max depth of 3 labels. This change enables openvswitch module to support a max depth of 3 labels in the ingress. Signed-off-by: Martin Varghese Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

net: openvswitch: Set OvS recirc_id from tc chain index

2019-09-06T12:59:18+00:00

Offloaded OvS datapath rules are translated one to one to tc rules, for example the following simplified OvS rule: recirc_id(0),in_port(dev1),eth_type(0x0800),ct_state(-trk) actions:ct(),recirc(2) Will be translated to the following tc rule: $ tc filter add dev dev1 ingress \ prio 1 chain 0 proto ip \ flower tcp ct_state -trk \ action ct pipe \ action goto chain 2 Received packets will first travel though tc, and if they aren't stolen by it, like in the above rule, they will continue to OvS datapath. Since we already did some actions (action ct in this case) which might modify the packets, and updated action stats, we would like to continue the proccessing with the correct recirc_id in OvS (here recirc_id(2)) where we left off. To support this, introduce a new skb extension for tc, which will be used for translating tc chain to ovs recirc_id to handle these miss cases. Last tc chain index will be set by tc goto chain action and read by OvS datapath. Signed-off-by: Paul Blakey Signed-off-by: Vlad Buslov Acked-by: Jiri Pirko Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

openvswitch: Clear the L4 portion of the key for "later" fragments.

2019-08-28T21:53:51+00:00

Only the first fragment in a datagram contains the L4 headers. When the Open vSwitch module parses a packet, it always sets the IP protocol field in the key, but can only set the L4 fields on the first fragment. The original behavior would not clear the L4 portion of the key, so garbage values would be sent in the key for "later" fragments. This patch clears the L4 fields in that circumstance to prevent sending those garbage values as part of the upcall. Signed-off-by: Justin Pettit Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

openvswitch: Properly set L4 keys on "later" IP fragments

2019-08-28T21:53:51+00:00

When IP fragments are reassembled before being sent to conntrack, the key from the last fragment is used. Unless there are reordering issues, the last fragment received will not contain the L4 ports, so the key for the reassembled datagram won't contain them. This patch updates the key once we have a reassembled datagram. The handle_fragments() function works on L3 headers so we pull the L3/L4 flow key update code from key_extract into a new function 'key_extract_l3l4'. Then we add a another new function ovs_flow_key_update_l3l4() and export it so that it is accessible by handle_fragments() for conntrack packet reassembly. Co-authored-by: Justin Pettit Signed-off-by: Greg Rose Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

net: openvswitch: rename flow_stats to sw_flow_stats

2019-07-20T04:27:45+00:00

There is a flow_stats structure defined in include/net/flow_offload.h and a follow up patch adds #include to net/sch_generic.h. This breaks compilation since OVS codebase includes net/sock.h which pulls in linux/filter.h which includes net/sch_generic.h. In file included from ./include/net/sch_generic.h:18:0, from ./include/linux/filter.h:25, from ./include/net/sock.h:59, from ./include/linux/tcp.h:19, from net/openvswitch/datapath.c:24 This definition takes precedence on OVS since it is placed in the networking core, so rename flow_stats in OVS to sw_flow_stats since this structure is contained in sw_flow. Signed-off-by: Pablo Neira Ayuso Acked-by: Jiri Pirko Signed-off-by: David S. Miller