kernel/net/ipv6/sit.c, branch linux-5.1.y

vrf: sit mtu should not be updated when vrf netdev is the link

2019-05-16T17:35:37Z

[ Upstream commit ff6ab32bd4e073976e4d8797b4d514a172cfe6cb ] VRF netdev mtu isn't typically set and have an mtu of 65536. When the link of a tunnel is set, the tunnel mtu is changed from 1480 to the link mtu minus tunnel header. In the case of VRF netdev is the link, then the tunnel mtu becomes 65516. So, fix it by not setting the tunnel mtu in this case. Signed-off-by: Stephen Suryaputra Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: sit: reset ip header pointer in ipip6_rcv

2019-04-05T01:34:23Z

ipip6 tunnels run iptunnel_pull_header on received skbs. This can determine the following use-after-free accessing iph pointer since the packet will be 'uncloned' running pskb_expand_head if it is a cloned gso skb (e.g if the packet has been sent though a veth device) [ 706.369655] BUG: KASAN: use-after-free in ipip6_rcv+0x1678/0x16e0 [sit] [ 706.449056] Read of size 1 at addr ffffe01b6bd855f5 by task ksoftirqd/1/= [ 706.669494] Hardware name: HPE ProLiant m400 Server/ProLiant m400 Server, BIOS U02 08/19/2016 [ 706.771839] Call trace: [ 706.801159] dump_backtrace+0x0/0x2f8 [ 706.845079] show_stack+0x24/0x30 [ 706.884833] dump_stack+0xe0/0x11c [ 706.925629] print_address_description+0x68/0x260 [ 706.982070] kasan_report+0x178/0x340 [ 707.025995] __asan_report_load1_noabort+0x30/0x40 [ 707.083481] ipip6_rcv+0x1678/0x16e0 [sit] [ 707.132623] tunnel64_rcv+0xd4/0x200 [tunnel4] [ 707.185940] ip_local_deliver_finish+0x3b8/0x988 [ 707.241338] ip_local_deliver+0x144/0x470 [ 707.289436] ip_rcv_finish+0x43c/0x14b0 [ 707.335447] ip_rcv+0x628/0x1138 [ 707.374151] __netif_receive_skb_core+0x1670/0x2600 [ 707.432680] __netif_receive_skb+0x28/0x190 [ 707.482859] process_backlog+0x1d0/0x610 [ 707.529913] net_rx_action+0x37c/0xf68 [ 707.574882] __do_softirq+0x288/0x1018 [ 707.619852] run_ksoftirqd+0x70/0xa8 [ 707.662734] smpboot_thread_fn+0x3a4/0x9e8 [ 707.711875] kthread+0x2c8/0x350 [ 707.750583] ret_from_fork+0x10/0x18 [ 707.811302] Allocated by task 16982: [ 707.854182] kasan_kmalloc.part.1+0x40/0x108 [ 707.905405] kasan_kmalloc+0xb4/0xc8 [ 707.948291] kasan_slab_alloc+0x14/0x20 [ 707.994309] __kmalloc_node_track_caller+0x158/0x5e0 [ 708.053902] __kmalloc_reserve.isra.8+0x54/0xe0 [ 708.108280] __alloc_skb+0xd8/0x400 [ 708.150139] sk_stream_alloc_skb+0xa4/0x638 [ 708.200346] tcp_sendmsg_locked+0x818/0x2b90 [ 708.251581] tcp_sendmsg+0x40/0x60 [ 708.292376] inet_sendmsg+0xf0/0x520 [ 708.335259] sock_sendmsg+0xac/0xf8 [ 708.377096] sock_write_iter+0x1c0/0x2c0 [ 708.424154] new_sync_write+0x358/0x4a8 [ 708.470162] __vfs_write+0xc4/0xf8 [ 708.510950] vfs_write+0x12c/0x3d0 [ 708.551739] ksys_write+0xcc/0x178 [ 708.592533] __arm64_sys_write+0x70/0xa0 [ 708.639593] el0_svc_handler+0x13c/0x298 [ 708.686646] el0_svc+0x8/0xc [ 708.739019] Freed by task 17: [ 708.774597] __kasan_slab_free+0x114/0x228 [ 708.823736] kasan_slab_free+0x10/0x18 [ 708.868703] kfree+0x100/0x3d8 [ 708.905320] skb_free_head+0x7c/0x98 [ 708.948204] skb_release_data+0x320/0x490 [ 708.996301] pskb_expand_head+0x60c/0x970 [ 709.044399] __iptunnel_pull_header+0x3b8/0x5d0 [ 709.098770] ipip6_rcv+0x41c/0x16e0 [sit] [ 709.146873] tunnel64_rcv+0xd4/0x200 [tunnel4] [ 709.200195] ip_local_deliver_finish+0x3b8/0x988 [ 709.255596] ip_local_deliver+0x144/0x470 [ 709.303692] ip_rcv_finish+0x43c/0x14b0 [ 709.349705] ip_rcv+0x628/0x1138 [ 709.388413] __netif_receive_skb_core+0x1670/0x2600 [ 709.446943] __netif_receive_skb+0x28/0x190 [ 709.497120] process_backlog+0x1d0/0x610 [ 709.544169] net_rx_action+0x37c/0xf68 [ 709.589131] __do_softirq+0x288/0x1018 [ 709.651938] The buggy address belongs to the object at ffffe01b6bd85580 which belongs to the cache kmalloc-1024 of size 1024 [ 709.804356] The buggy address is located 117 bytes inside of 1024-byte region [ffffe01b6bd85580, ffffe01b6bd85980) [ 709.946340] The buggy address belongs to the page: [ 710.003824] page:ffff7ff806daf600 count:1 mapcount:0 mapping:ffffe01c4001f600 index:0x0 [ 710.099914] flags: 0xfffff8000000100(slab) [ 710.149059] raw: 0fffff8000000100 dead000000000100 dead000000000200 ffffe01c4001f600 [ 710.242011] raw: 0000000000000000 0000000000380038 00000001ffffffff 0000000000000000 [ 710.334966] page dumped because: kasan: bad access detected Fix it resetting iph pointer after iptunnel_pull_header Fixes: a09a4c8dd1ec ("tunnels: Remove encapsulation offloads on decap") Tested-by: Jianlin Shi Signed-off-by: Lorenzo Bianconi Signed-off-by: David S. Miller

net: sit: fix UBSAN Undefined behaviour in check_6rd

2019-03-11T17:32:45Z

In func check_6rd,tunnel->ip6rd.relay_prefixlen may equal to 32,so UBSAN complain about it. UBSAN: Undefined behaviour in net/ipv6/sit.c:781:47 shift exponent 32 is too large for 32-bit type 'unsigned int' CPU: 6 PID: 20036 Comm: syz-executor.0 Not tainted 4.19.27 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xca/0x13e lib/dump_stack.c:113 ubsan_epilogue+0xe/0x81 lib/ubsan.c:159 __ubsan_handle_shift_out_of_bounds+0x293/0x2e8 lib/ubsan.c:425 check_6rd.constprop.9+0x433/0x4e0 net/ipv6/sit.c:781 try_6rd net/ipv6/sit.c:806 [inline] ipip6_tunnel_xmit net/ipv6/sit.c:866 [inline] sit_tunnel_xmit+0x141c/0x2720 net/ipv6/sit.c:1033 __netdev_start_xmit include/linux/netdevice.h:4300 [inline] netdev_start_xmit include/linux/netdevice.h:4309 [inline] xmit_one net/core/dev.c:3243 [inline] dev_hard_start_xmit+0x17c/0x780 net/core/dev.c:3259 __dev_queue_xmit+0x1656/0x2500 net/core/dev.c:3829 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0xa36/0x2290 net/ipv6/ip6_output.c:120 ip6_finish_output+0x3e7/0xa20 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x1e2/0x720 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0x99/0x170 net/ipv6/output_core.c:176 ip6_send_skb+0x9d/0x2f0 net/ipv6/ip6_output.c:1697 ip6_push_pending_frames+0xc0/0x100 net/ipv6/ip6_output.c:1717 rawv6_push_pending_frames net/ipv6/raw.c:616 [inline] rawv6_sendmsg+0x2435/0x3530 net/ipv6/raw.c:946 inet_sendmsg+0xf8/0x5c0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xc8/0x110 net/socket.c:631 ___sys_sendmsg+0x6cf/0x890 net/socket.c:2114 __sys_sendmsg+0xf0/0x1b0 net/socket.c:2152 do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: linmiaohe Signed-off-by: David S. Miller

net: sit: fix memory leak in sit_init_net()

2019-03-02T08:53:23Z

If register_netdev() is failed to register sitn->fb_tunnel_dev, it will go to err_reg_dev and forget to free netdev(sitn->fb_tunnel_dev). BUG: memory leak unreferenced object 0xffff888378daad00 (size 512): comm "syz-executor.1", pid 4006, jiffies 4295121142 (age 16.115s) hex dump (first 32 bytes): 00 e6 ed c0 83 88 ff ff 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000d6dcb63e>] kvmalloc include/linux/mm.h:577 [inline] [<00000000d6dcb63e>] kvzalloc include/linux/mm.h:585 [inline] [<00000000d6dcb63e>] netif_alloc_netdev_queues net/core/dev.c:8380 [inline] [<00000000d6dcb63e>] alloc_netdev_mqs+0x600/0xcc0 net/core/dev.c:8970 [<00000000867e172f>] sit_init_net+0x295/0xa40 net/ipv6/sit.c:1848 [<00000000871019fa>] ops_init+0xad/0x3e0 net/core/net_namespace.c:129 [<00000000319507f6>] setup_net+0x2ba/0x690 net/core/net_namespace.c:314 [<0000000087db4f96>] copy_net_ns+0x1dc/0x330 net/core/net_namespace.c:437 [<0000000057efc651>] create_new_namespaces+0x382/0x730 kernel/nsproxy.c:107 [<00000000676f83de>] copy_namespaces+0x2ed/0x3d0 kernel/nsproxy.c:165 [<0000000030b74bac>] copy_process.part.27+0x231e/0x6db0 kernel/fork.c:1919 [<00000000fff78746>] copy_process kernel/fork.c:1713 [inline] [<00000000fff78746>] _do_fork+0x1bc/0xe90 kernel/fork.c:2224 [<000000001c2e0d1c>] do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290 [<00000000ec48bd44>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<0000000039acff8a>] 0xffffffffffffffff Signed-off-by: Mao Wenan Signed-off-by: David S. Miller

sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()

2019-02-07T18:48:42Z

If we disabled IPv6 from the kernel command line (ipv6.disable=1), we should not call ip6_err_gen_icmpv6_unreach(). This: ip link add sit1 type sit local 192.0.2.1 remote 192.0.2.2 ttl 1 ip link set sit1 up ip addr add 198.51.100.1/24 dev sit1 ping 198.51.100.2 if IPv6 is disabled at boot time, will crash the kernel. v2: there's no need to use in6_dev_get(), use __in6_dev_get() instead, as we only need to check that idev exists and we are under rcu_read_lock() (from netif_receive_skb_internal()). Reported-by: Jianlin Shi Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error") Cc: Oussama Ghorbel Signed-off-by: Hangbin Liu Reviewed-by: Stefano Brivio Signed-off-by: David S. Miller

ip: validate header length on virtual device xmit

2019-01-01T20:05:02Z

KMSAN detected read beyond end of buffer in vti and sit devices when passing truncated packets with PF_PACKET. The issue affects additional ip tunnel devices. Extend commit 76c0ddd8c3a6 ("ip6_tunnel: be careful when accessing the inner header") and commit ccfec9e5cb2d ("ip_tunnel: be careful when accessing the inner header"). Move the check to a separate helper and call at the start of each ndo_start_xmit function in net/ipv4 and net/ipv6. Minor changes: - convert dev_kfree_skb to kfree_skb on error path, as dev_kfree_skb calls consume_skb which is not for error paths. - use pskb_network_may_pull even though that is pedantic here, as the same as pskb_may_pull for devices without llheaders. - do not cache ipv6 hdrs if used only once (unsafe across pskb_may_pull, was more relevant to earlier patch) Reported-by: syzbot Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

net-ipv4: remove 2 always zero parameters from ipv4_redirect()

2018-09-27T03:30:55Z

(the parameters in question are mark and flow_flags) Reviewed-by: David Ahern Signed-off-by: Maciej Żenczykowski Signed-off-by: David S. Miller

net-ipv4: remove 2 always zero parameters from ipv4_update_pmtu()

2018-09-27T03:30:55Z

(the parameters in question are mark and flow_flags) Reviewed-by: David Ahern Signed-off-by: Maciej Żenczykowski Signed-off-by: David S. Miller

ip6_tunnel: remove magic mtu value 0xFFF8

2018-06-01T17:56:30Z

I don't know where this value comes from (probably a copy and paste and paste and paste ...). Let's use standard values which are a bit greater. Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/netdev-vger-cvs.git/commit/?id=e5afd356a411a Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller

ipv6: sit: better validate user provided tunnel names

2018-04-05T19:16:15Z

Use dev_valid_name() to make sure user does not provide illegal device name. syzbot caught the following bug : BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300 [inline] BUG: KASAN: stack-out-of-bounds in ipip6_tunnel_locate+0x63b/0xaa0 net/ipv6/sit.c:254 Write of size 33 at addr ffff8801b64076d8 by task syzkaller932654/4453 CPU: 0 PID: 4453 Comm: syzkaller932654 Not tainted 4.16.0+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b9/0x29f lib/dump_stack.c:53 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 strlcpy include/linux/string.h:300 [inline] ipip6_tunnel_locate+0x63b/0xaa0 net/ipv6/sit.c:254 ipip6_tunnel_ioctl+0xe71/0x241b net/ipv6/sit.c:1221 dev_ifsioc+0x43e/0xb90 net/core/dev_ioctl.c:334 dev_ioctl+0x69a/0xcc0 net/core/dev_ioctl.c:525 sock_ioctl+0x47e/0x680 net/socket.c:1015 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1cf/0x1650 fs/ioctl.c:684 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 SYSC_ioctl fs/ioctl.c:708 [inline] SyS_ioctl+0x24/0x30 fs/ioctl.c:706 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller