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2025-06-17net: ipv4: Add a flags argument to iptunnel_xmit(), udp_tunnel_xmit_skb()Petr Machata
iptunnel_xmit() erases the contents of the SKB control block. In order to be able to set particular IPCB flags on the SKB, add a corresponding parameter, and propagate it to udp_tunnel_xmit_skb() as well. In one of the following patches, VXLAN driver will use this facility to mark packets as subject to IP multicast routing. Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Acked-by: Antonio Quartulli <antonio@openvpn.net> Link: https://patch.msgid.link/89c9daf9f2dc088b6b92ccebcc929f51742de91f.1750113335.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-03net: fix geneve_opt length integer overflowLin Ma
struct geneve_opt uses 5 bit length for each single option, which means every vary size option should be smaller than 128 bytes. However, all current related Netlink policies cannot promise this length condition and the attacker can exploit a exact 128-byte size option to *fake* a zero length option and confuse the parsing logic, further achieve heap out-of-bounds read. One example crash log is like below: [ 3.905425] ================================================================== [ 3.905925] BUG: KASAN: slab-out-of-bounds in nla_put+0xa9/0xe0 [ 3.906255] Read of size 124 at addr ffff888005f291cc by task poc/177 [ 3.906646] [ 3.906775] CPU: 0 PID: 177 Comm: poc-oob-read Not tainted 6.1.132 #1 [ 3.907131] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 3.907784] Call Trace: [ 3.907925] <TASK> [ 3.908048] dump_stack_lvl+0x44/0x5c [ 3.908258] print_report+0x184/0x4be [ 3.909151] kasan_report+0xc5/0x100 [ 3.909539] kasan_check_range+0xf3/0x1a0 [ 3.909794] memcpy+0x1f/0x60 [ 3.909968] nla_put+0xa9/0xe0 [ 3.910147] tunnel_key_dump+0x945/0xba0 [ 3.911536] tcf_action_dump_1+0x1c1/0x340 [ 3.912436] tcf_action_dump+0x101/0x180 [ 3.912689] tcf_exts_dump+0x164/0x1e0 [ 3.912905] fw_dump+0x18b/0x2d0 [ 3.913483] tcf_fill_node+0x2ee/0x460 [ 3.914778] tfilter_notify+0xf4/0x180 [ 3.915208] tc_new_tfilter+0xd51/0x10d0 [ 3.918615] rtnetlink_rcv_msg+0x4a2/0x560 [ 3.919118] netlink_rcv_skb+0xcd/0x200 [ 3.919787] netlink_unicast+0x395/0x530 [ 3.921032] netlink_sendmsg+0x3d0/0x6d0 [ 3.921987] __sock_sendmsg+0x99/0xa0 [ 3.922220] __sys_sendto+0x1b7/0x240 [ 3.922682] __x64_sys_sendto+0x72/0x90 [ 3.922906] do_syscall_64+0x5e/0x90 [ 3.923814] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 [ 3.924122] RIP: 0033:0x7e83eab84407 [ 3.924331] Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 faf [ 3.925330] RSP: 002b:00007ffff505e370 EFLAGS: 00000202 ORIG_RAX: 000000000000002c [ 3.925752] RAX: ffffffffffffffda RBX: 00007e83eaafa740 RCX: 00007e83eab84407 [ 3.926173] RDX: 00000000000001a8 RSI: 00007ffff505e3c0 RDI: 0000000000000003 [ 3.926587] RBP: 00007ffff505f460 R08: 00007e83eace1000 R09: 000000000000000c [ 3.926977] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffff505f3c0 [ 3.927367] R13: 00007ffff505f5c8 R14: 00007e83ead1b000 R15: 00005d4fbbe6dcb8 Fix these issues by enforing correct length condition in related policies. Fixes: 925d844696d9 ("netfilter: nft_tunnel: add support for geneve opts") Fixes: 4ece47787077 ("lwtunnel: add options setting and dumping for geneve") Fixes: 0ed5269f9e41 ("net/sched: add tunnel option support to act_tunnel_key") Fixes: 0a6e77784f49 ("net/sched: allow flower to match tunnel options") Signed-off-by: Lin Ma <linma@zju.edu.cn> Reviewed-by: Xin Long <lucien.xin@gmail.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Link: https://patch.msgid.link/20250402165632.6958-1-linma@zju.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-02tunnels: Accept PACKET_HOST in skb_tunnel_check_pmtu().Guillaume Nault
Because skb_tunnel_check_pmtu() doesn't handle PACKET_HOST packets, commit 30a92c9e3d6b ("openvswitch: Set the skbuff pkt_type for proper pmtud support.") forced skb->pkt_type to PACKET_OUTGOING for openvswitch packets that are sent using the OVS_ACTION_ATTR_OUTPUT action. This allowed such packets to invoke the iptunnel_pmtud_check_icmp() or iptunnel_pmtud_check_icmpv6() helpers and thus trigger PMTU update on the input device. However, this also broke other parts of PMTU discovery. Since these packets don't have the PACKET_HOST type anymore, they won't trigger the sending of ICMP Fragmentation Needed or Packet Too Big messages to remote hosts when oversized (see the skb_in->pkt_type condition in __icmp_send() for example). These two skb->pkt_type checks are therefore incompatible as one requires skb->pkt_type to be PACKET_HOST, while the other requires it to be anything but PACKET_HOST. It makes sense to not trigger ICMP messages for non-PACKET_HOST packets as these messages should be generated only for incoming l2-unicast packets. However there doesn't seem to be any reason for skb_tunnel_check_pmtu() to ignore PACKET_HOST packets. Allow both cases to work by allowing skb_tunnel_check_pmtu() to work on PACKET_HOST packets and not overriding skb->pkt_type in openvswitch anymore. Fixes: 30a92c9e3d6b ("openvswitch: Set the skbuff pkt_type for proper pmtud support.") Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Aaron Conole <aconole@redhat.com> Tested-by: Aaron Conole <aconole@redhat.com> Link: https://patch.msgid.link/eac941652b86fddf8909df9b3bf0d97bc9444793.1743208264.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-01ip_tunnel: convert __be16 tunnel flags to bitmapsAlexander Lobakin
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 <horms@kernel.org> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-01ip_tunnel: use a separate struct to store tunnel params in the kernelAlexander Lobakin
Unlike IPv6 tunnels which use purely-kernel __ip6_tnl_parm structure to store params inside the kernel, IPv4 tunnel code uses the same ip_tunnel_parm which is being used to talk with the userspace. This makes it difficult to alter or add any fields or use a different format for whatever data. Define struct ip_tunnel_parm_kern, a 1:1 copy of ip_tunnel_parm for now, and use it throughout the code. Define the pieces, where the copy user <-> kernel happens, as standalone functions, and copy the data there field-by-field, so that the kernel-side structure could be easily modified later on and the users wouldn't have to care about this. Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-03tunnels: fix out of bounds access when building IPv6 PMTU errorAntoine Tenart
If the ICMPv6 error is built from a non-linear skb we get the following splat, BUG: KASAN: slab-out-of-bounds in do_csum+0x220/0x240 Read of size 4 at addr ffff88811d402c80 by task netperf/820 CPU: 0 PID: 820 Comm: netperf Not tainted 6.8.0-rc1+ #543 ... kasan_report+0xd8/0x110 do_csum+0x220/0x240 csum_partial+0xc/0x20 skb_tunnel_check_pmtu+0xeb9/0x3280 vxlan_xmit_one+0x14c2/0x4080 vxlan_xmit+0xf61/0x5c00 dev_hard_start_xmit+0xfb/0x510 __dev_queue_xmit+0x7cd/0x32a0 br_dev_queue_push_xmit+0x39d/0x6a0 Use skb_checksum instead of csum_partial who cannot deal with non-linear SKBs. Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-04tunnels: fix kasan splat when generating ipv4 pmtu errorFlorian Westphal
If we try to emit an icmp error in response to a nonliner skb, we get BUG: KASAN: slab-out-of-bounds in ip_compute_csum+0x134/0x220 Read of size 4 at addr ffff88811c50db00 by task iperf3/1691 CPU: 2 PID: 1691 Comm: iperf3 Not tainted 6.5.0-rc3+ #309 [..] kasan_report+0x105/0x140 ip_compute_csum+0x134/0x220 iptunnel_pmtud_build_icmp+0x554/0x1020 skb_tunnel_check_pmtu+0x513/0xb80 vxlan_xmit_one+0x139e/0x2ef0 vxlan_xmit+0x1867/0x2760 dev_hard_start_xmit+0x1ee/0x4f0 br_dev_queue_push_xmit+0x4d1/0x660 [..] ip_compute_csum() cannot deal with nonlinear skbs, so avoid it. After this change, splat is gone and iperf3 is no longer stuck. Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Florian Westphal <fw@strlen.de> Link: https://lore.kernel.org/r/20230803152653.29535-2-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-03net: Add helper function to parse netlink msg of ip_tunnel_parmLiu Jian
Add ip_tunnel_netlink_parms to parse netlink msg of ip_tunnel_parm. Reduces duplicate code, no actual functional changes. Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-03net: Add helper function to parse netlink msg of ip_tunnel_encapLiu Jian
Add ip_tunnel_netlink_encap_parms to parse netlink msg of ip_tunnel_encap. Reduces duplicate code, no actual functional changes. Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-27tunnels: do not assume mac header is set in skb_tunnel_check_pmtu()Eric Dumazet
Recently added debug in commit f9aefd6b2aa3 ("net: warn if mac header was not set") caught a bug in skb_tunnel_check_pmtu(), as shown in this syzbot report [1]. In ndo_start_xmit() paths, there is really no need to use skb->mac_header, because skb->data is supposed to point at it. [1] WARNING: CPU: 1 PID: 8604 at include/linux/skbuff.h:2784 skb_mac_header_len include/linux/skbuff.h:2784 [inline] WARNING: CPU: 1 PID: 8604 at include/linux/skbuff.h:2784 skb_tunnel_check_pmtu+0x5de/0x2f90 net/ipv4/ip_tunnel_core.c:413 Modules linked in: CPU: 1 PID: 8604 Comm: syz-executor.3 Not tainted 5.19.0-rc2-syzkaller-00443-g8720bd951b8e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:skb_mac_header_len include/linux/skbuff.h:2784 [inline] RIP: 0010:skb_tunnel_check_pmtu+0x5de/0x2f90 net/ipv4/ip_tunnel_core.c:413 Code: 00 00 00 00 fc ff df 4c 89 fa 48 c1 ea 03 80 3c 02 00 0f 84 b9 fe ff ff 4c 89 ff e8 7c 0f d7 f9 e9 ac fe ff ff e8 c2 13 8a f9 <0f> 0b e9 28 fc ff ff e8 b6 13 8a f9 48 8b 54 24 70 48 b8 00 00 00 RSP: 0018:ffffc90002e4f520 EFLAGS: 00010212 RAX: 0000000000000324 RBX: ffff88804d5fd500 RCX: ffffc90005b52000 RDX: 0000000000040000 RSI: ffffffff87f05e3e RDI: 0000000000000003 RBP: ffffc90002e4f650 R08: 0000000000000003 R09: 000000000000ffff R10: 000000000000ffff R11: 0000000000000000 R12: 000000000000ffff R13: 0000000000000000 R14: 000000000000ffcd R15: 000000000000001f FS: 00007f3babba9700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000080 CR3: 0000000075319000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> geneve_xmit_skb drivers/net/geneve.c:927 [inline] geneve_xmit+0xcf8/0x35d0 drivers/net/geneve.c:1107 __netdev_start_xmit include/linux/netdevice.h:4805 [inline] netdev_start_xmit include/linux/netdevice.h:4819 [inline] __dev_direct_xmit+0x500/0x730 net/core/dev.c:4309 dev_direct_xmit include/linux/netdevice.h:3007 [inline] packet_direct_xmit+0x1b8/0x2c0 net/packet/af_packet.c:282 packet_snd net/packet/af_packet.c:3073 [inline] packet_sendmsg+0x21f4/0x55d0 net/packet/af_packet.c:3104 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 ____sys_sendmsg+0x6eb/0x810 net/socket.c:2489 ___sys_sendmsg+0xf3/0x170 net/socket.c:2543 __sys_sendmsg net/socket.c:2572 [inline] __do_sys_sendmsg net/socket.c:2581 [inline] __se_sys_sendmsg net/socket.c:2579 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2579 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f3baaa89109 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3babba9168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f3baab9bf60 RCX: 00007f3baaa89109 RDX: 0000000000000000 RSI: 0000000020000a00 RDI: 0000000000000003 RBP: 00007f3baaae305d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe74f2543f R14: 00007f3babba9300 R15: 0000000000022000 </TASK> Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-01-08net: ip_tunnel: clean up endianness conversionsJulian Wiedmann
sparse complains about some harmless endianness issues: > net/ipv4/ip_tunnel_core.c:225:43: warning: cast to restricted __be16 > net/ipv4/ip_tunnel_core.c:225:43: warning: incorrect type in initializer (different base types) > net/ipv4/ip_tunnel_core.c:225:43: expected restricted __be16 [usertype] mtu > net/ipv4/ip_tunnel_core.c:225:43: got unsigned short [usertype] iptunnel_pmtud_build_icmp() uses the wrong flavour of byte-order conversion when storing the MTU into the ICMPv4 packet. Use htons(), just like iptunnel_pmtud_build_icmpv6() does. > net/ipv4/ip_tunnel_core.c:248:35: warning: cast from restricted __be16 > net/ipv4/ip_tunnel_core.c:248:35: warning: incorrect type in argument 3 (different base types) > net/ipv4/ip_tunnel_core.c:248:35: expected unsigned short type > net/ipv4/ip_tunnel_core.c:248:35: got restricted __be16 [usertype] > net/ipv4/ip_tunnel_core.c:341:35: warning: cast from restricted __be16 > net/ipv4/ip_tunnel_core.c:341:35: warning: incorrect type in argument 3 (different base types) > net/ipv4/ip_tunnel_core.c:341:35: expected unsigned short type > net/ipv4/ip_tunnel_core.c:341:35: got restricted __be16 [usertype] eth_header() wants the Ethertype in host-order, use the correct flavour of byte-order conversion. > net/ipv4/ip_tunnel_core.c:600:45: warning: restricted __be16 degrades to integer > net/ipv4/ip_tunnel_core.c:609:30: warning: incorrect type in assignment (different base types) > net/ipv4/ip_tunnel_core.c:609:30: expected int type > net/ipv4/ip_tunnel_core.c:609:30: got restricted __be16 [usertype] > net/ipv4/ip_tunnel_core.c:619:30: warning: incorrect type in assignment (different base types) > net/ipv4/ip_tunnel_core.c:619:30: expected int type > net/ipv4/ip_tunnel_core.c:619:30: got restricted __be16 [usertype] > net/ipv4/ip_tunnel_core.c:629:30: warning: incorrect type in assignment (different base types) > net/ipv4/ip_tunnel_core.c:629:30: expected int type > net/ipv4/ip_tunnel_core.c:629:30: got restricted __be16 [usertype] The TUNNEL_* types are big-endian, so adjust the type of the local variable in ip_tun_parse_opts(). Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Link: https://lore.kernel.org/r/20210107144008.25777-1-jwi@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-12Merge https://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-09net: remove ip_tunnel_get_stats64Heiner Kallweit
After having migrated all users remove ip_tunnel_get_stats64(). Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-09tunnels: Fix off-by-one in lower MTU bounds for ICMP/ICMPv6 repliesStefano Brivio
Jianlin reports that a bridged IPv6 VXLAN endpoint, carrying IPv6 packets over a link with a PMTU estimation of exactly 1350 bytes, won't trigger ICMPv6 Packet Too Big replies when the encapsulated datagrams exceed said PMTU value. VXLAN over IPv6 adds 70 bytes of overhead, so an ICMPv6 reply indicating 1280 bytes as inner MTU would be legitimate and expected. This comes from an off-by-one error I introduced in checks added as part of commit 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets"), whose purpose was to prevent sending ICMPv6 Packet Too Big messages with an MTU lower than the smallest permissible IPv6 link MTU, i.e. 1280 bytes. In iptunnel_pmtud_check_icmpv6(), avoid triggering a reply only if the advertised MTU would be less than, and not equal to, 1280 bytes. Also fix the analogous comparison for IPv4, that is, skip the ICMP reply only if the resulting MTU is strictly less than 576 bytes. This becomes apparent while running the net/pmtu.sh bridged VXLAN or GENEVE selftests with adjusted lower-link MTU values. Using e.g. GENEVE, setting ll_mtu to the values reported below, in the test_pmtu_ipvX_over_bridged_vxlanY_or_geneveY_exception() test function, we can see failures on the following tests: test | ll_mtu -------------------------------|-------- pmtu_ipv4_br_geneve4_exception | 626 pmtu_ipv6_br_geneve4_exception | 1330 pmtu_ipv6_br_geneve6_exception | 1350 owing to the different tunneling overheads implied by the corresponding configurations. Reported-by: Jianlin Shi <jishi@redhat.com> Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Link: https://lore.kernel.org/r/4f5fc2f33bfdf8409549fafd4f952b008bf04d63.1604681709.git.sbrivio@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-13iptunnel: use new function dev_fetch_sw_netstatsHeiner Kallweit
Simplify the code by using new function dev_fetch_sw_netstats(). Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Link: https://lore.kernel.org/r/050f9a83-b195-a3d6-edbd-91a59040be21@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-14lwtunnel: only keep the available bits when setting vxlan md->gbpXin Long
As we can see from vxlan_build/parse_gbp_hdr(), when processing metadata on vxlan rx/tx path, only dont_learn/policy_applied/policy_id fields can be set to or parse from the packet for vxlan gbp option. So do the mask when set it in lwtunnel, as it does in act_tunnel_key and cls_flower. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-05ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUMStefano Brivio
On architectures defining _HAVE_ARCH_IPV6_CSUM, we get csum_ipv6_magic() defined by means of arch checksum.h headers. On other architectures, we actually need to include net/ip6_checksum.h to be able to use it. Without this include, building with defconfig breaks at least for s390. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-04tunnels: PMTU discovery support for directly bridged IP packetsStefano Brivio
It's currently possible to bridge Ethernet tunnels carrying IP packets directly to external interfaces without assigning them addresses and routes on the bridged network itself: this is the case for UDP tunnels bridged with a standard bridge or by Open vSwitch. PMTU discovery is currently broken with those configurations, because the encapsulation effectively decreases the MTU of the link, and while we are able to account for this using PMTU discovery on the lower layer, we don't have a way to relay ICMP or ICMPv6 messages needed by the sender, because we don't have valid routes to it. On the other hand, as a tunnel endpoint, we can't fragment packets as a general approach: this is for instance clearly forbidden for VXLAN by RFC 7348, section 4.3: VTEPs MUST NOT fragment VXLAN packets. Intermediate routers may fragment encapsulated VXLAN packets due to the larger frame size. The destination VTEP MAY silently discard such VXLAN fragments. The same paragraph recommends that the MTU over the physical network accomodates for encapsulations, but this isn't a practical option for complex topologies, especially for typical Open vSwitch use cases. Further, it states that: Other techniques like Path MTU discovery (see [RFC1191] and [RFC1981]) MAY be used to address this requirement as well. Now, PMTU discovery already works for routed interfaces, we get route exceptions created by the encapsulation device as they receive ICMP Fragmentation Needed and ICMPv6 Packet Too Big messages, and we already rebuild those messages with the appropriate MTU and route them back to the sender. Add the missing bits for bridged cases: - checks in skb_tunnel_check_pmtu() to understand if it's appropriate to trigger a reply according to RFC 1122 section 3.2.2 for ICMP and RFC 4443 section 2.4 for ICMPv6. This function is already called by UDP tunnels - a new function generating those ICMP or ICMPv6 replies. We can't reuse icmp_send() and icmp6_send() as we don't see the sender as a valid destination. This doesn't need to be generic, as we don't cover any other type of ICMP errors given that we only provide an encapsulation function to the sender While at it, make the MTU check in skb_tunnel_check_pmtu() accurate: we might receive GSO buffers here, and the passed headroom already includes the inner MAC length, so we don't have to account for it a second time (that would imply three MAC headers on the wire, but there are just two). This issue became visible while bridging IPv6 packets with 4500 bytes of payload over GENEVE using IPv4 with a PMTU of 4000. Given the 50 bytes of encapsulation headroom, we would advertise MTU as 3950, and we would reject fragmented IPv6 datagrams of 3958 bytes size on the wire. We're exclusively dealing with network MTU here, though, so we could get Ethernet frames up to 3964 octets in that case. v2: - moved skb_tunnel_check_pmtu() to ip_tunnel_core.c (David Ahern) - split IPv4/IPv6 functions (David Ahern) Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-30net: ip_tunnel: add header_ops for layer 3 devicesJason A. Donenfeld
Some devices that take straight up layer 3 packets benefit from having a shared header_ops so that AF_PACKET sockets can inject packets that are recognized. This shared infrastructure will be used by other drivers that currently can't inject packets using AF_PACKET. It also exposes the parser function, as it is useful in standalone form too. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29net: add net available in build_stateAlexander Aring
The build_state callback of lwtunnel doesn't contain the net namespace structure yet. This patch will add it so we can check on specific address configuration at creation time of rpl source routes. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21lwtunnel: check erspan options before allocating tun_infoXin Long
As Jakub suggested on another patch, it's better to do the check on erspan options before allocating memory. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21lwtunnel: be STRICT to validate the new LWTUNNEL_IP(6)_OPTSXin Long
LWTUNNEL_IP(6)_OPTS are the new items in ip(6)_tun_policy, which are parsed by nla_parse_nested_deprecated(). We should check it strictly by setting .strict_start_type = LWTUNNEL_IP(6)_OPTS. This patch also adds missing LWTUNNEL_IP6_OPTS in ip6_tun_policy. Fixes: 4ece47787077 ("lwtunnel: add options setting and dumping for geneve") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-20lwtunnel: add support for multiple geneve optsXin Long
geneve RFC (draft-ietf-nvo3-geneve-14) allows a geneve packet to carry multiple geneve opts, so it's necessary for lwtunnel to support adding multiple geneve opts in one lwtunnel route. But vxlan and erspan opts are still only allowed to add one option. With this patch, iproute2 could make it like: # ip r a 1.1.1.0/24 encap ip id 1 geneve_opts 0:0:12121212,1:2:12121212 \ dst 10.1.0.2 dev geneve1 # ip r a 1.1.1.0/24 encap ip id 1 vxlan_opts 456 \ dst 10.1.0.2 dev erspan1 # ip r a 1.1.1.0/24 encap ip id 1 erspan_opts 1:123:0:0 \ dst 10.1.0.2 dev erspan1 Which are pretty much like cls_flower and act_tunnel_key. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-18lwtunnel: change to use nla_put_u8 for LWTUNNEL_IP_OPT_ERSPAN_VERXin Long
LWTUNNEL_IP_OPT_ERSPAN_VER is u8 type, and nla_put_u8 should have been used instead of nla_put_u32(). This is a copy-paste error. Fixes: b0a21810bd5e ("lwtunnel: add options setting and dumping for erspan") Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-11lwtunnel: ignore any TUNNEL_OPTIONS_PRESENT flags set by usersXin Long
TUNNEL_OPTIONS_PRESENT (TUNNEL_GENEVE_OPT|TUNNEL_VXLAN_OPT| TUNNEL_ERSPAN_OPT) flags should be set only according to tb[LWTUNNEL_IP_OPTS], which is done in ip_tun_parse_opts(). When setting info key.tun_flags, the TUNNEL_OPTIONS_PRESENT bits in tb[LWTUNNEL_IP(6)_FLAGS] passed from users should be ignored. While at it, replace all (TUNNEL_GENEVE_OPT|TUNNEL_VXLAN_OPT| TUNNEL_ERSPAN_OPT) with 'TUNNEL_OPTIONS_PRESENT'. Fixes: 3093fbe7ff4b ("route: Per route IP tunnel metadata via lightweight tunnel") Fixes: 32a2b002ce61 ("ipv6: route: per route IP tunnel metadata via lightweight tunnel") Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-11lwtunnel: get nlsize for erspan options properlyXin Long
erspan v1 has OPT_ERSPAN_INDEX while erspan v2 has OPT_ERSPAN_DIR and OPT_ERSPAN_HWID attributes, and they require different nlsize when dumping. So this patch is to get nlsize for erspan options properly according to erspan version. Fixes: b0a21810bd5e ("lwtunnel: add options setting and dumping for erspan") Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-11lwtunnel: change to use nla_parse_nested on new optionsXin Long
As the new options added in kernel, all should always use strict parsing from the beginning with nla_parse_nested(), instead of nla_parse_nested_deprecated(). Fixes: b0a21810bd5e ("lwtunnel: add options setting and dumping for erspan") Fixes: edf31cbb1502 ("lwtunnel: add options setting and dumping for vxlan") Fixes: 4ece47787077 ("lwtunnel: add options setting and dumping for geneve") Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06lwtunnel: add options setting and dumping for erspanXin Long
Based on the code framework built on the last patch, to support setting and dumping for vxlan, we only need to add ip_tun_parse_opts_erspan() for .build_state and ip_tun_fill_encap_opts_erspan() for .fill_encap and if (tun_flags & TUNNEL_ERSPAN_OPT) for .get_encap_size. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06lwtunnel: add options setting and dumping for vxlanXin Long
Based on the code framework built on the last patch, to support setting and dumping for vxlan, we only need to add ip_tun_parse_opts_vxlan() for .build_state and ip_tun_fill_encap_opts_vxlan() for .fill_encap and if (tun_flags & TUNNEL_VXLAN_OPT) for .get_encap_size. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06lwtunnel: add options setting and dumping for geneveXin Long
To add options setting and dumping, .build_state(), .fill_encap() and .get_encap_size() in ip_tun_lwt_ops needs to be extended: ip_tun_build_state(): ip_tun_parse_opts(): ip_tun_parse_opts_geneve() ip_tun_fill_encap_info(): ip_tun_fill_encap_opts(): ip_tun_fill_encap_opts_geneve() ip_tun_encap_nlsize() ip_tun_opts_nlsize(): if (tun_flags & TUNNEL_GENEVE_OPT) ip_tun_parse_opts(), ip_tun_fill_encap_opts() and ip_tun_opts_nlsize() processes LWTUNNEL_IP_OPTS. ip_tun_parse_opts_geneve(), ip_tun_fill_encap_opts_geneve() and if (tun_flags & TUNNEL_GENEVE_OPT) processes LWTUNNEL_IP_OPTS_GENEVE. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06lwtunnel: add options process for cmp_encapXin Long
When comparing two tun_info, dst_cache member should have been skipped, as dst_cache is a per cpu pointer and they are always different values even in two tun_info with the same keys. So this patch is to skip dst_cache member and compare the key, mode and options_len only. For the future opts setting support, also to compare options. Fixes: 2d79849903e0 ("lwtunnel: ip tunnel: fix multiple routes with different encap") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06lwtunnel: add options process for arp requestXin Long
Without options copied to the dst tun_info in iptunnel_metadata_reply() called by arp_process for handling arp_request, the generated arp_reply packet may be dropped or sent out with wrong options for some tunnels like erspan and vxlan, and the traffic will break. Fixes: 63d008a4e9ee ("ipv4: send arp replies to the correct tunnel") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-18ip_tunnel: allow not to count pkts on tstats by setting skb's dev to NULLXin Long
iptunnel_xmit() works as a common function, also used by a udp tunnel which doesn't have to have a tunnel device, like how TIPC works with udp media. In these cases, we should allow not to count pkts on dev's tstats, so that udp tunnel can work with no tunnel device safely. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 269Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 21 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141334.228102212@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-24ip_tunnel: Add dst_cache support in lwtunnel_state of ip tunnelwenxu
The lwtunnel_state is not init the dst_cache Which make the ip_md_tunnel_xmit can't use the dst_cache. It will lookup route table every packets. Signed-off-by: wenxu <wenxu@ucloud.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Pull in bug fixes before respinning my net-next pull request. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-24iptunnel: Set tun_flags in the iptunnel_metadata_reply from srcwenxu
ip l add tun type gretap external ip r a 10.0.0.2 encap ip id 1000 dst 172.168.0.2 key dev tun ip a a 10.0.0.1/24 dev tun The peer arp request to 10.0.0.1 with tunnel_id, but the arp reply only set the tun_id but not the tun_flags with TUNNEL_KEY. The arp reply packet don't contain tun_id field. Signed-off-by: wenxu <wenxu@ucloud.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2018-11-17ip_tunnel: don't force DF when MTU is lockedSabrina Dubroca
The various types of tunnels running over IPv4 can ask to set the DF bit to do PMTU discovery. However, PMTU discovery is subject to the threshold set by the net.ipv4.route.min_pmtu sysctl, and is also disabled on routes with "mtu lock". In those cases, we shouldn't set the DF bit. This patch makes setting the DF bit conditional on the route's MTU locking state. This issue seems to be older than git history. Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08ipv4/tunnel: use __vlan_hwaccel helpersMichał Mirosław
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10net/ipv4: Update ip_tunnel_metadata_cnt static key to modern apiDavidlohr Bueso
No changes in refcount semantics -- key init is false; replace static_key_slow_inc|dec with static_branch_inc|dec static_key_false with static_branch_unlikely Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25net: store port/representator id in metadata_dstJakub Kicinski
Switches and modern SR-IOV enabled NICs may multiplex traffic from Port representators and control messages over single set of hardware queues. Control messages and muxed traffic may need ordered delivery. Those requirements make it hard to comfortably use TC infrastructure today unless we have a way of attaching metadata to skbs at the upper device. Because single set of queues is used for many netdevs stopping TC/sched queues of all of them reliably is impossible and lower device has to retreat to returning NETDEV_TX_BUSY and usually has to take extra locks on the fastpath. This patch attempts to enable port/representative devs to attach metadata to skbs which carry port id. This way representatives can be queueless and all queuing can be performed at the lower netdev in the usual way. Traffic arriving on the port/representative interfaces will be have metadata attached and will subsequently be queued to the lower device for transmission. The lower device should recognize the metadata and translate it to HW specific format which is most likely either a special header inserted before the network headers or descriptor/metadata fields. Metadata is associated with the lower device by storing the netdev pointer along with port id so that if TC decides to redirect or mirror the new netdev will not try to interpret it. This is mostly for SR-IOV devices since switches don't have lower netdevs today. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-30net: add extack arg to lwtunnel build stateDavid Ahern
Pass extack arg down to lwtunnel_build_state and the build_state callbacks. Add messages for failures in lwtunnel_build_state, and add the extarg to nla_parse where possible in the build_state callbacks. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-13netlink: pass extended ACK struct to parsing functionsJohannes Berg
Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-30lwtunnel: remove device arg to lwtunnel_build_stateDavid Ahern
Nothing about lwt state requires a device reference, so remove the input argument. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Two trivial overlapping changes conflicts in MPLS and mlx5. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-24net: Specify the owning module for lwtunnel opsRobert Shearman
Modules implementing lwtunnel ops should not be allowed to unload while there is state alive using those ops, so specify the owning module for all lwtunnel ops. Signed-off-by: Robert Shearman <rshearma@brocade.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-08net: make ndo_get_stats64 a void functionstephen hemminger
The network device operation for reading statistics is only called in one place, and it ignores the return value. Having a structure return value is potentially confusing because some future driver could incorrectly assume that the return value was used. Fix all drivers with ndo_get_stats64 to have a void function. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03ipv4: allow local fragmentation in ip_finish_output_gso()Lance Richardson
Some configurations (e.g. geneve interface with default MTU of 1500 over an ethernet interface with 1500 MTU) result in the transmission of packets that exceed the configured MTU. While this should be considered to be a "bad" configuration, it is still allowed and should not result in the sending of packets that exceed the configured MTU. Fix by dropping the assumption in ip_finish_output_gso() that locally originated gso packets will never need fragmentation. Basic testing using iperf (observing CPU usage and bandwidth) have shown no measurable performance impact for traffic not requiring fragmentation. Fixes: c7ba65d7b649 ("net: ip: push gso skb forwarding handling down the stack") Reported-by: Jan Tluka <jtluka@redhat.com> Signed-off-by: Lance Richardson <lrichard@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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