user/sven/linux.git/net, branch v5.10.98

tcp: add missing tcp_skb_can_collapse() test in tcp_shift_skb_data()

2022-02-05T11:37:57Z

commit b67985be400969578d4d4b17299714c0e5d2c07b upstream. tcp_shift_skb_data() might collapse three packets into a larger one. P_A, P_B, P_C -> P_ABC Historically, it used a single tcp_skb_can_collapse_to(P_A) call, because it was enough. In commit 85712484110d ("tcp: coalesce/collapse must respect MPTCP extensions"), this call was replaced by a call to tcp_skb_can_collapse(P_A, P_B) But the now needed test over P_C has been missed. This probably broke MPTCP. Then later, commit 9b65b17db723 ("net: avoid double accounting for pure zerocopy skbs") added an extra condition to tcp_skb_can_collapse(), but the missing call from tcp_shift_skb_data() is also breaking TCP zerocopy, because P_A and P_C might have different skb_zcopy_pure() status. Fixes: 85712484110d ("tcp: coalesce/collapse must respect MPTCP extensions") Fixes: 9b65b17db723 ("net: avoid double accounting for pure zerocopy skbs") Signed-off-by: Eric Dumazet Cc: Mat Martineau Cc: Talal Ahmad Cc: Arjun Roy Cc: Willem de Bruijn Acked-by: Soheil Hassas Yeganeh Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20220201184640.756716-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

af_packet: fix data-race in packet_setsockopt / packet_setsockopt

2022-02-05T11:37:57Z

commit e42e70ad6ae2ae511a6143d2e8da929366e58bd9 upstream. When packet_setsockopt( PACKET_FANOUT_DATA ) reads po->fanout, no lock is held, meaning that another thread can change po->fanout. Given that po->fanout can only be set once during the socket lifetime (it is only cleared from fanout_release()), we can use READ_ONCE()/WRITE_ONCE() to document the race. BUG: KCSAN: data-race in packet_setsockopt / packet_setsockopt write to 0xffff88813ae8e300 of 8 bytes by task 14653 on cpu 0: fanout_add net/packet/af_packet.c:1791 [inline] packet_setsockopt+0x22fe/0x24a0 net/packet/af_packet.c:3931 __sys_setsockopt+0x209/0x2a0 net/socket.c:2180 __do_sys_setsockopt net/socket.c:2191 [inline] __se_sys_setsockopt net/socket.c:2188 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2188 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88813ae8e300 of 8 bytes by task 14654 on cpu 1: packet_setsockopt+0x691/0x24a0 net/packet/af_packet.c:3935 __sys_setsockopt+0x209/0x2a0 net/socket.c:2180 __do_sys_setsockopt net/socket.c:2191 [inline] __se_sys_setsockopt net/socket.c:2188 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2188 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000000000000000 -> 0xffff888106f8c000 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 14654 Comm: syz-executor.3 Not tainted 5.16.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 47dceb8ecdc1 ("packet: add classic BPF fanout mode") Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Reported-by: syzbot Link: https://lore.kernel.org/r/20220201022358.330621-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

rtnetlink: make sure to refresh master_dev/m_ops in __rtnl_newlink()

2022-02-05T11:37:56Z

commit c6f6f2444bdbe0079e41914a35081530d0409963 upstream. While looking at one unrelated syzbot bug, I found the replay logic in __rtnl_newlink() to potentially trigger use-after-free. It is better to clear master_dev and m_ops inside the loop, in case we have to replay it. Fixes: ba7d49b1f0f8 ("rtnetlink: provide api for getting and setting slave info") Signed-off-by: Eric Dumazet Cc: Jiri Pirko Link: https://lore.kernel.org/r/20220201012106.216495-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: sched: fix use-after-free in tc_new_tfilter()

2022-02-05T11:37:56Z

commit 04c2a47ffb13c29778e2a14e414ad4cb5a5db4b5 upstream. Whenever tc_new_tfilter() jumps back to replay: label, we need to make sure @q and @chain local variables are cleared again, or risk use-after-free as in [1] For consistency, apply the same fix in tc_ctl_chain() BUG: KASAN: use-after-free in mini_qdisc_pair_swap+0x1b9/0x1f0 net/sched/sch_generic.c:1581 Write of size 8 at addr ffff8880985c4b08 by task syz-executor.4/1945 CPU: 0 PID: 1945 Comm: syz-executor.4 Not tainted 5.17.0-rc1-syzkaller-00495-gff58831fa02d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 mini_qdisc_pair_swap+0x1b9/0x1f0 net/sched/sch_generic.c:1581 tcf_chain_head_change_item net/sched/cls_api.c:372 [inline] tcf_chain0_head_change.isra.0+0xb9/0x120 net/sched/cls_api.c:386 tcf_chain_tp_insert net/sched/cls_api.c:1657 [inline] tcf_chain_tp_insert_unique net/sched/cls_api.c:1707 [inline] tc_new_tfilter+0x1e67/0x2350 net/sched/cls_api.c:2086 rtnetlink_rcv_msg+0x80d/0xb80 net/core/rtnetlink.c:5583 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ____sys_sendmsg+0x331/0x810 net/socket.c:2413 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467 __sys_sendmmsg+0x195/0x470 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x99/0x100 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+0x44/0xae RIP: 0033:0x7f2647172059 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:00007f2645aa5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f2647285100 RCX: 00007f2647172059 RDX: 040000000000009f RSI: 00000000200002c0 RDI: 0000000000000006 RBP: 00007f26471cc08d R08: 0000000000000000 R09: 0000000000000000 R10: 9e00000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffb3f7f02f R14: 00007f2645aa5300 R15: 0000000000022000 Allocated by task 1944: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 kmalloc_node include/linux/slab.h:604 [inline] kzalloc_node include/linux/slab.h:726 [inline] qdisc_alloc+0xac/0xa10 net/sched/sch_generic.c:941 qdisc_create.constprop.0+0xce/0x10f0 net/sched/sch_api.c:1211 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5592 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ____sys_sendmsg+0x331/0x810 net/socket.c:2413 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467 __sys_sendmmsg+0x195/0x470 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x99/0x100 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+0x44/0xae Freed by task 3609: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x130/0x160 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3509 [inline] kfree+0xcb/0x280 mm/slub.c:4562 rcu_do_batch kernel/rcu/tree.c:2527 [inline] rcu_core+0x7b8/0x1540 kernel/rcu/tree.c:2778 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3026 [inline] call_rcu+0xb1/0x740 kernel/rcu/tree.c:3106 qdisc_put_unlocked+0x6f/0x90 net/sched/sch_generic.c:1109 tcf_block_release+0x86/0x90 net/sched/cls_api.c:1238 tc_new_tfilter+0xc0d/0x2350 net/sched/cls_api.c:2148 rtnetlink_rcv_msg+0x80d/0xb80 net/core/rtnetlink.c:5583 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ____sys_sendmsg+0x331/0x810 net/socket.c:2413 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467 __sys_sendmmsg+0x195/0x470 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x99/0x100 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+0x44/0xae The buggy address belongs to the object at ffff8880985c4800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 776 bytes inside of 1024-byte region [ffff8880985c4800, ffff8880985c4c00) The buggy address belongs to the page: page:ffffea0002617000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x985c0 head:ffffea0002617000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888010c41dc0 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1941, ts 1038999441284, free_ts 1033444432829 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab mm/slub.c:1944 [inline] new_slab+0x28a/0x3b0 mm/slub.c:2004 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105 slab_alloc_node mm/slub.c:3196 [inline] slab_alloc mm/slub.c:3238 [inline] __kmalloc+0x2fb/0x340 mm/slub.c:4420 kmalloc include/linux/slab.h:586 [inline] kzalloc include/linux/slab.h:715 [inline] __register_sysctl_table+0x112/0x1090 fs/proc/proc_sysctl.c:1335 neigh_sysctl_register+0x2c8/0x5e0 net/core/neighbour.c:3787 devinet_sysctl_register+0xb1/0x230 net/ipv4/devinet.c:2618 inetdev_init+0x286/0x580 net/ipv4/devinet.c:278 inetdev_event+0xa8a/0x15d0 net/ipv4/devinet.c:1532 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1919 call_netdevice_notifiers_extack net/core/dev.c:1931 [inline] call_netdevice_notifiers net/core/dev.c:1945 [inline] register_netdevice+0x1073/0x1500 net/core/dev.c:9698 veth_newlink+0x59c/0xa90 drivers/net/veth.c:1722 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 release_pages+0x748/0x1220 mm/swap.c:956 tlb_batch_pages_flush mm/mmu_gather.c:50 [inline] tlb_flush_mmu_free mm/mmu_gather.c:243 [inline] tlb_flush_mmu+0xe9/0x6b0 mm/mmu_gather.c:250 zap_pte_range mm/memory.c:1441 [inline] zap_pmd_range mm/memory.c:1490 [inline] zap_pud_range mm/memory.c:1519 [inline] zap_p4d_range mm/memory.c:1540 [inline] unmap_page_range+0x1d1d/0x2a30 mm/memory.c:1561 unmap_single_vma+0x198/0x310 mm/memory.c:1606 unmap_vmas+0x16b/0x2f0 mm/memory.c:1638 exit_mmap+0x201/0x670 mm/mmap.c:3178 __mmput+0x122/0x4b0 kernel/fork.c:1114 mmput+0x56/0x60 kernel/fork.c:1135 exit_mm kernel/exit.c:507 [inline] do_exit+0xa3c/0x2a30 kernel/exit.c:793 do_group_exit+0xd2/0x2f0 kernel/exit.c:935 __do_sys_exit_group kernel/exit.c:946 [inline] __se_sys_exit_group kernel/exit.c:944 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:944 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+0x44/0xae Memory state around the buggy address: ffff8880985c4a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880985c4a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880985c4b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880985c4b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880985c4c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc Fixes: 470502de5bdb ("net: sched: unlock rules update API") Signed-off-by: Eric Dumazet Cc: Vlad Buslov Cc: Jiri Pirko Cc: Cong Wang Reported-by: syzbot Link: https://lore.kernel.org/r/20220131172018.3704490-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: bridge: vlan: fix memory leak in __allowed_ingress

2022-02-01T16:25:48Z

[ Upstream commit fd20d9738395cf8e27d0a17eba34169699fccdff ] When using per-vlan state, if vlan snooping and stats are disabled, untagged or priority-tagged ingress frame will go to check pvid state. If the port state is forwarding and the pvid state is not learning/forwarding, untagged or priority-tagged frame will be dropped but skb memory is not freed. Should free skb when __allowed_ingress returns false. Fixes: a580c76d534c ("net: bridge: vlan: add per-vlan state") Signed-off-by: Tim Yi Acked-by: Nikolay Aleksandrov Link: https://lore.kernel.org/r/20220127074953.12632-1-tim.yi@pica8.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: tcp: send zero IPID in SYNACK messages

2022-02-01T16:25:47Z

[ Upstream commit 970a5a3ea86da637471d3cd04d513a0755aba4bf ] In commit 431280eebed9 ("ipv4: tcp: send zero IPID for RST and ACK sent in SYN-RECV and TIME-WAIT state") we took care of some ctl packets sent by TCP. It turns out we need to use a similar strategy for SYNACK packets. By default, they carry IP_DF and IPID==0, but there are ways to ask them to use the hashed IP ident generator and thus be used to build off-path attacks. (Ref: Off-Path TCP Exploits of the Mixed IPID Assignment) One of this way is to force (before listener is started) echo 1 >/proc/sys/net/ipv4/ip_no_pmtu_disc Another way is using forged ICMP ICMP_FRAG_NEEDED with a very small MTU (like 68) to force a false return from ip_dont_fragment() In this patch, ip_build_and_send_pkt() uses the following heuristics. 1) Most SYNACK packets are smaller than IPV4_MIN_MTU and therefore can use IP_DF regardless of the listener or route pmtu setting. 2) In case the SYNACK packet is bigger than IPV4_MIN_MTU, we use prandom_u32() generator instead of the IPv4 hashed ident one. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: Ray Che Reviewed-by: David Ahern Cc: Geoff Alexander Cc: Willy Tarreau Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv4: raw: lock the socket in raw_bind()

2022-02-01T16:25:47Z

[ Upstream commit 153a0d187e767c68733b8e9f46218eb1f41ab902 ] For some reason, raw_bind() forgot to lock the socket. BUG: KCSAN: data-race in __ip4_datagram_connect / raw_bind write to 0xffff8881170d4308 of 4 bytes by task 5466 on cpu 0: raw_bind+0x1b0/0x250 net/ipv4/raw.c:739 inet_bind+0x56/0xa0 net/ipv4/af_inet.c:443 __sys_bind+0x14b/0x1b0 net/socket.c:1697 __do_sys_bind net/socket.c:1708 [inline] __se_sys_bind net/socket.c:1706 [inline] __x64_sys_bind+0x3d/0x50 net/socket.c:1706 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881170d4308 of 4 bytes by task 5468 on cpu 1: __ip4_datagram_connect+0xb7/0x7b0 net/ipv4/datagram.c:39 ip4_datagram_connect+0x2a/0x40 net/ipv4/datagram.c:89 inet_dgram_connect+0x107/0x190 net/ipv4/af_inet.c:576 __sys_connect_file net/socket.c:1900 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1917 __do_sys_connect net/socket.c:1927 [inline] __se_sys_connect net/socket.c:1924 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:1924 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00000000 -> 0x0003007f Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 5468 Comm: syz-executor.5 Not tainted 5.17.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: bridge: vlan: fix single net device option dumping

2022-02-01T16:25:47Z

[ Upstream commit dcb2c5c6ca9b9177f04abaf76e5a983d177c9414 ] When dumping vlan options for a single net device we send the same entries infinitely because user-space expects a 0 return at the end but we keep returning skb->len and restarting the dump on retry. Fix it by returning the value from br_vlan_dump_dev() if it completed or there was an error. The only case that must return skb->len is when the dump was incomplete and needs to continue (-EMSGSIZE). Reported-by: Benjamin Poirier Fixes: 8dcea187088b ("net: bridge: vlan: add rtm definitions and dump support") Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

Revert "ipv6: Honor all IPv6 PIO Valid Lifetime values"

2022-02-01T16:25:47Z

[ Upstream commit 36268983e90316b37000a005642af42234dabb36 ] This reverts commit b75326c201242de9495ff98e5d5cff41d7fc0d9d. This commit breaks Linux compatibility with USGv6 tests. The RFC this commit was based on is actually an expired draft: no published RFC currently allows the new behaviour it introduced. Without full IETF endorsement, the flash renumbering scenario this patch was supposed to enable is never going to work, as other IPv6 equipements on the same LAN will keep the 2 hours limit. Fixes: b75326c20124 ("ipv6: Honor all IPv6 PIO Valid Lifetime values") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ipv4: fix ip option filtering for locally generated fragments

2022-02-01T16:25:46Z

[ Upstream commit 27a8caa59babb96c5890569e131bc0eb6d45daee ] During IP fragmentation we sanitize IP options. This means overwriting options which should not be copied with NOPs. Only the first fragment has the original, full options. ip_fraglist_prepare() copies the IP header and options from previous fragment to the next one. Commit 19c3401a917b ("net: ipv4: place control buffer handling away from fragmentation iterators") moved sanitizing options before ip_fraglist_prepare() which means options are sanitized and then overwritten again with the old values. Fixing this is not enough, however, nor did the sanitization work prior to aforementioned commit. ip_options_fragment() (which does the sanitization) uses ipcb->opt.optlen for the length of the options. ipcb->opt of fragments is not populated (it's 0), only the head skb has the state properly built. So even when called at the right time ip_options_fragment() does nothing. This seems to date back all the way to v2.5.44 when the fast path for pre-fragmented skbs had been introduced. Prior to that ip_options_build() would have been called for every fragment (in fact ever since v2.5.44 the fragmentation handing in ip_options_build() has been dead code, I'll clean it up in -next). In the original patch (see Link) caixf mentions fixing the handling for fragments other than the second one, but I'm not sure how _any_ fragment could have had their options sanitized with the code as it stood. Tested with python (MTU on lo lowered to 1000 to force fragmentation): import socket s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) s.setsockopt(socket.IPPROTO_IP, socket.IP_OPTIONS, bytearray([7,4,5,192, 20|0x80,4,1,0])) s.sendto(b'1'*2000, ('127.0.0.1', 1234)) Before: IP (tos 0x0, ttl 64, id 1053, offset 0, flags [+], proto UDP (17), length 996, options (RR [bad length 4] [bad ptr 5] 192.148.4.1,,RA value 256)) localhost.36500 > localhost.search-agent: UDP, length 2000 IP (tos 0x0, ttl 64, id 1053, offset 968, flags [+], proto UDP (17), length 996, options (RR [bad length 4] [bad ptr 5] 192.148.4.1,,RA value 256)) localhost > localhost: udp IP (tos 0x0, ttl 64, id 1053, offset 1936, flags [none], proto UDP (17), length 100, options (RR [bad length 4] [bad ptr 5] 192.148.4.1,,RA value 256)) localhost > localhost: udp After: IP (tos 0x0, ttl 96, id 42549, offset 0, flags [+], proto UDP (17), length 996, options (RR [bad length 4] [bad ptr 5] 192.148.4.1,,RA value 256)) localhost.51607 > localhost.search-agent: UDP, bad length 2000 > 960 IP (tos 0x0, ttl 96, id 42549, offset 968, flags [+], proto UDP (17), length 996, options (NOP,NOP,NOP,NOP,RA value 256)) localhost > localhost: udp IP (tos 0x0, ttl 96, id 42549, offset 1936, flags [none], proto UDP (17), length 100, options (NOP,NOP,NOP,NOP,RA value 256)) localhost > localhost: udp RA (20 | 0x80) is now copied as expected, RR (7) is "NOPed out". Link: https://lore.kernel.org/netdev/20220107080559.122713-1-ooppublic@163.com/ Fixes: 19c3401a917b ("net: ipv4: place control buffer handling away from fragmentation iterators") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: caixf Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller Signed-off-by: Sasha Levin