summaryrefslogtreecommitdiffstats
path: root/net/ipv6
Commit message (Collapse)AuthorAgeFilesLines
* ipv6: drop incoming packets having a v4mapped source addressEric Dumazet2019-12-191-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3 upstream. This began with a syzbot report. syzkaller was injecting IPv6 TCP SYN packets having a v4mapped source address. After an unsuccessful 4-tuple lookup, TCP creates a request socket (SYN_RECV) and calls reqsk_queue_hash_req() reqsk_queue_hash_req() calls sk_ehashfn(sk) At this point we have AF_INET6 sockets, and the heuristic used by sk_ehashfn() to either hash the IPv4 or IPv6 addresses is to use ipv6_addr_v4mapped(&sk->sk_v6_daddr) For the particular spoofed packet, we end up hashing V4 addresses which were not initialized by the TCP IPv6 stack, so KMSAN fired a warning. I first fixed sk_ehashfn() to test both source and destination addresses, but then faced various problems, including user-space programs like packetdrill that had similar assumptions. Instead of trying to fix the whole ecosystem, it is better to admit that we have a dual stack behavior, and that we can not build linux kernels without V4 stack anyway. The dual stack API automatically forces the traffic to be IPv4 if v4mapped addresses are used at bind() or connect(), so it makes no sense to allow IPv6 traffic to use the same v4mapped class. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: Fix the link time qualifier of 'ping_v6_proc_exit_net()'Christophe JAILLET2019-11-221-1/+1
| | | | | | | | | | | | commit d23dbc479a8e813db4161a695d67da0e36557846 upstream. The '.exit' functions from 'pernet_operations' structure should be marked as __net_exit, not __net_init. Fixes: d862e5461423 ("net: ipv6: Implement /proc/net/icmp6.") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* mld: fix memory leak in mld_del_delrec()Eric Dumazet2019-11-221-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a84d016479896b5526a2cc54784e6ffc41c9d6f6 upstream. Similar to the fix done for IPv4 in commit e5b1c6c6277d ("igmp: fix memory leak in igmpv3_del_delrec()"), we need to make sure mca_tomb and mca_sources are not blindly overwritten. Using swap() then a call to ip6_mc_clear_src() will take care of the missing free. BUG: memory leak unreferenced object 0xffff888117d9db00 (size 64): comm "syz-executor247", pid 6918, jiffies 4294943989 (age 25.350s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 fe 88 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000005b463030>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<000000005b463030>] slab_post_alloc_hook mm/slab.h:522 [inline] [<000000005b463030>] slab_alloc mm/slab.c:3319 [inline] [<000000005b463030>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548 [<00000000939cbf94>] kmalloc include/linux/slab.h:552 [inline] [<00000000939cbf94>] kzalloc include/linux/slab.h:748 [inline] [<00000000939cbf94>] ip6_mc_add1_src net/ipv6/mcast.c:2236 [inline] [<00000000939cbf94>] ip6_mc_add_src+0x31f/0x420 net/ipv6/mcast.c:2356 [<00000000d8972221>] ip6_mc_source+0x4a8/0x600 net/ipv6/mcast.c:449 [<000000002b203d0d>] do_ipv6_setsockopt.isra.0+0x1b92/0x1dd0 net/ipv6/ipv6_sockglue.c:748 [<000000001f1e2d54>] ipv6_setsockopt+0x89/0xd0 net/ipv6/ipv6_sockglue.c:944 [<00000000c8f7bdf9>] udpv6_setsockopt+0x4e/0x90 net/ipv6/udp.c:1558 [<000000005a9a0c5e>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3139 [<00000000910b37b2>] __sys_setsockopt+0x10f/0x220 net/socket.c:2084 [<00000000e9108023>] __do_sys_setsockopt net/socket.c:2100 [inline] [<00000000e9108023>] __se_sys_setsockopt net/socket.c:2097 [inline] [<00000000e9108023>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2097 [<00000000f4818160>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296 [<000000008d367e8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when set link down") Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: flowlabel: fl6_sock_lookup() must use atomic_inc_not_zeroEric Dumazet2019-10-051-3/+4
| | | | | | | | | | | | | | | commit 65a3c497c0e965a552008db8bc2653f62bc925a1 upstream. Before taking a refcount, make sure the object is not already scheduled for deletion. Same fix is needed in ipv6_flowlabel_opt() Fixes: 18367681a10b ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* inet: switch IP ID generator to siphashEric Dumazet2019-08-131-15/+16
| | | | | | | | | | | | | | | | | | | commit df453700e8d81b1bdafdf684365ee2b9431fb702 upstream. According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: hash net ptr into fragmentation bucket selectionHannes Frederic Sowa2019-08-133-11/+13
| | | | | | | | | | | | | | commit 5a352dd0a3aac03b443c94828dfd7144261c8636 upstream. As namespaces are sometimes used with overlapping ip address ranges, we should also use the namespace as input to the hash to select the ip fragmentation counter bucket. Cc: Eric Dumazet <edumazet@google.com> Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: call ipv6_proxy_select_ident instead of ipv6_select_ident in ↵Sabrina Dubroca2019-08-131-5/+3
| | | | | | | | | | | | | | | | | | | | | | | udp6_ufo_fragment commit 8e199dfd82ee097b522b00344af6448715d8ee0c upstream. Matt Grant reported frequent crashes in ipv6_select_ident when udp6_ufo_fragment is called from openvswitch on a skb that doesn't have a dst_entry set. ipv6_proxy_select_ident generates the frag_id without using the dst associated with the skb. This approach was suggested by Vladislav Yasevich. Fixes: 0508c07f5e0c ("ipv6: Select fragment id during UFO segmentation if not set.") Cc: Vladislav Yasevich <vyasevic@redhat.com> Reported-by: Matt Grant <matt@mattgrant.net.nz> Tested-by: Matt Grant <matt@mattgrant.net.nz> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: Make __ipv6_select_ident staticVlad Yasevich2019-08-131-1/+2
| | | | | | | | | | | | commit 8381eacf5c3b35cf7755f4bc521c4d56d24c1cd9 upstream. Make __ipv6_select_ident() static as it isn't used outside the file. Fixes: 0508c07f5e0c9 (ipv6: Select fragment id during UFO segmentation if not set.) Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: Fix fragment id assignment on LE arches.Vlad Yasevich2019-08-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 51f30770e50eb787200f30a79105e2615b379334 upstream. Recent commit: 0508c07f5e0c94f38afd5434e8b2a55b84553077 Author: Vlad Yasevich <vyasevich@gmail.com> Date: Tue Feb 3 16:36:15 2015 -0500 ipv6: Select fragment id during UFO segmentation if not set. Introduced a bug on LE in how ipv6 fragment id is assigned. This was cought by nightly sparce check: Resolve the following sparce error: net/ipv6/output_core.c:57:38: sparse: incorrect type in assignment (different base types) net/ipv6/output_core.c:57:38: expected restricted __be32 [usertype] ip6_frag_id net/ipv6/output_core.c:57:38: got unsigned int [unsigned] [assigned] [usertype] id Fixes: 0508c07f5e0c9 (ipv6: Select fragment id during UFO segmentation if not set.) Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: Select fragment id during UFO segmentation if not set.Vlad Yasevich2019-08-133-21/+44
| | | | | | | | | | | | | | | | | | | | | | | commit 0508c07f5e0c94f38afd5434e8b2a55b84553077 upstream. If the IPv6 fragment id has not been set and we perform fragmentation due to UFO, select a new fragment id. We now consider a fragment id of 0 as unset and if id selection process returns 0 (after all the pertrubations), we set it to 0x80000000, thus giving us ample space not to create collisions with the next packet we may have to fragment. When doing UFO integrity checking, we also select the fragment id if it has not be set yet. This is stored into the skb_shinfo() thus allowing UFO to function correclty. This patch also removes duplicate fragment id generation code and moves ipv6_select_ident() into the header as it may be used during GSO. Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* Revert "inet: update the IP ID generation algorithm to higher standards."Ben Hutchings2019-08-131-3/+0
| | | | | | | | This reverts commit 8b197d3ce585d6777197e0633d71e5af7d98cb35, which was a stable-specific improvement to IP ID selection. I will apply the upstream changes instead. Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6/flowlabel: wait rcu grace period before put_pid()Eric Dumazet2019-08-131-7/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6c0afef5fb0c27758f4d52b2210c61b6bd8b4470 upstream. syzbot was able to catch a use-after-free read in pid_nr_ns() [1] ip6fl_seq_show() seems to use RCU protection, dereferencing fl->owner.pid but fl_free() releases fl->owner.pid before rcu grace period is started. [1] BUG: KASAN: use-after-free in pid_nr_ns+0x128/0x140 kernel/pid.c:407 Read of size 4 at addr ffff888094012a04 by task syz-executor.0/18087 CPU: 0 PID: 18087 Comm: syz-executor.0 Not tainted 5.1.0-rc6+ #89 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 pid_nr_ns+0x128/0x140 kernel/pid.c:407 ip6fl_seq_show+0x2f8/0x4f0 net/ipv6/ip6_flowlabel.c:794 seq_read+0xad3/0x1130 fs/seq_file.c:268 proc_reg_read+0x1fe/0x2c0 fs/proc/inode.c:227 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x4a9/0x660 fs/read_write.c:922 vfs_readv+0xf0/0x160 fs/read_write.c:984 kernel_readv fs/splice.c:358 [inline] default_file_splice_read+0x475/0x890 fs/splice.c:413 do_splice_to+0x12a/0x190 fs/splice.c:876 splice_direct_to_actor+0x2d2/0x970 fs/splice.c:953 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062 do_sendfile+0x597/0xd00 fs/read_write.c:1443 __do_sys_sendfile64 fs/read_write.c:1498 [inline] __se_sys_sendfile64 fs/read_write.c:1490 [inline] __x64_sys_sendfile64+0x15a/0x220 fs/read_write.c:1490 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f300d24bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458da9 RDX: 00000000200000c0 RSI: 0000000000000008 RDI: 0000000000000007 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000005a R11: 0000000000000246 R12: 00007f300d24c6d4 R13: 00000000004c5fa3 R14: 00000000004da748 R15: 00000000ffffffff Allocated by task 17543: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3393 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3555 alloc_pid+0x55/0x8f0 kernel/pid.c:168 copy_process.part.0+0x3b08/0x7980 kernel/fork.c:1932 copy_process kernel/fork.c:1709 [inline] _do_fork+0x257/0xfd0 kernel/fork.c:2226 __do_sys_clone kernel/fork.c:2333 [inline] __se_sys_clone kernel/fork.c:2327 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2327 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7789: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3499 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3765 put_pid.part.0+0x111/0x150 kernel/pid.c:111 put_pid+0x20/0x30 kernel/pid.c:105 fl_free+0xbe/0xe0 net/ipv6/ip6_flowlabel.c:102 ip6_fl_gc+0x295/0x3e0 net/ipv6/ip6_flowlabel.c:152 call_timer_fn+0x190/0x720 kernel/time/timer.c:1325 expire_timers kernel/time/timer.c:1362 [inline] __run_timers kernel/time/timer.c:1681 [inline] __run_timers kernel/time/timer.c:1649 [inline] run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694 __do_softirq+0x266/0x95a kernel/softirq.c:293 The buggy address belongs to the object at ffff888094012a00 which belongs to the cache pid_2 of size 88 The buggy address is located 4 bytes inside of 88-byte region [ffff888094012a00, ffff888094012a58) The buggy address belongs to the page: page:ffffea0002500480 count:1 mapcount:0 mapping:ffff88809a483080 index:0xffff888094012980 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00018a3508 ffffea0002524a88 ffff88809a483080 raw: ffff888094012980 ffff888094012000 000000010000001b 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888094012900: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff888094012980: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc >ffff888094012a00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ^ ffff888094012a80: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff888094012b00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc Fixes: 4f82f45730c6 ("net ip6 flowlabel: Make owner a union of struct pid * and kuid_t") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: Move the release_net() call too, not that it does anything.] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: invert flowlabel sharing check in process and user modeWillem de Bruijn2019-08-131-2/+2
| | | | | | | | | | | | | | | commit 95c169251bf734aa555a1e8043e4d88ec97a04ec upstream. A request for a flowlabel fails in process or user exclusive mode must fail if the caller pid or uid does not match. Invert the test. Previously, the test was unsafe wrt PID recycling, but indeed tested for inequality: fl1->owner != fl->owner Fixes: 4f82f45730c68 ("net ip6 flowlabel: Make owner a union of struct pid* and kuid_t") Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp: do not use ipv6 header for ipv4 flowEric Dumazet2019-08-131-4/+4
| | | | | | | | | | | | | | | commit 89e4130939a20304f4059ab72179da81f5347528 upstream. When a dual stack tcp listener accepts an ipv4 flow, it should not attempt to use an ipv6 header or tcp_v6_iif() helper. Fixes: 1397ed35f22d ("ipv6: add flowinfo for tcp6 pkt_options for all cases") Fixes: df3687ffc665 ("ipv6: add the IPV6_FL_F_REFLECT flag to IPV6_FL_A_GET") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel moduleSu Yanjun2019-08-131-0/+4
| | | | | | | | | | | | | | commit 6ee02a54ef990a71bf542b6f0a4e3321de9d9c66 upstream. When unloading xfrm6_tunnel module, xfrm6_tunnel_fini directly frees the xfrm6_tunnel_spi_kmem. Maybe someone has gotten the xfrm6_tunnel_spi, so need to wait it. Fixes: 91cc3bb0b04ff("xfrm6_tunnel: RCU conversion") Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockoptXin Long2019-08-131-3/+8
| | | | | | | | | | | | | | | | | | | | | commit 99253eb750fda6a644d5188fb26c43bad8d5a745 upstream. Commit 5e1859fbcc3c ("ipv4: ipmr: various fixes and cleanups") fixed the issue for ipv4 ipmr: ip_mroute_setsockopt() & ip_mroute_getsockopt() should not access/set raw_sk(sk)->ipmr_table before making sure the socket is a raw socket, and protocol is IGMP The same fix should be done for ipv6 ipmr as well. This patch can fix the panic caused by overwriting the same offset as ipmr_table as in raw_sk(sk) when accessing other type's socket by ip_mroute_setsockopt(). Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip6mr: Do not call __IP6_INC_STATS() from preemptible contextIdo Schimmel2019-07-091-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 87c11f1ddbbad38ad8bad47af133a8208985fbdf upstream. Similar to commit 44f49dd8b5a6 ("ipmr: fix possible race resulting from improper usage of IP_INC_STATS_BH() in preemptible context."), we cannot assume preemption is disabled when incrementing the counter and accessing a per-CPU variable. Preemption can be enabled when we add a route in process context that corresponds to packets stored in the unresolved queue, which are then forwarded using this route [1]. Fix this by using IP6_INC_STATS() which takes care of disabling preemption on architectures where it is needed. [1] [ 157.451447] BUG: using __this_cpu_add() in preemptible [00000000] code: smcrouted/2314 [ 157.460409] caller is ip6mr_forward2+0x73e/0x10e0 [ 157.460434] CPU: 3 PID: 2314 Comm: smcrouted Not tainted 5.0.0-rc7-custom-03635-g22f2712113f1 #1336 [ 157.460449] Hardware name: Mellanox Technologies Ltd. MSN2100-CB2FO/SA001017, BIOS 5.6.5 06/07/2016 [ 157.460461] Call Trace: [ 157.460486] dump_stack+0xf9/0x1be [ 157.460553] check_preemption_disabled+0x1d6/0x200 [ 157.460576] ip6mr_forward2+0x73e/0x10e0 [ 157.460705] ip6_mr_forward+0x9a0/0x1510 [ 157.460771] ip6mr_mfc_add+0x16b3/0x1e00 [ 157.461155] ip6_mroute_setsockopt+0x3cb/0x13c0 [ 157.461384] do_ipv6_setsockopt.isra.8+0x348/0x4060 [ 157.462013] ipv6_setsockopt+0x90/0x110 [ 157.462036] rawv6_setsockopt+0x4a/0x120 [ 157.462058] __sys_setsockopt+0x16b/0x340 [ 157.462198] __x64_sys_setsockopt+0xbf/0x160 [ 157.462220] do_syscall_64+0x14d/0x610 [ 157.462349] entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 0912ea38de61 ("[IPV6] MROUTE: Add stats in multicast routing module method ip6_mr_forward().") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reported-by: Amit Cohen <amitc@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* inet: update the IP ID generation algorithm to higher standards.Amit Klein2019-05-111-0/+3
| | | | | | | | | | | | | | | | | Commit 355b98553789 ("netns: provide pure entropy for net_hash_mix()") makes net_hash_mix() return a true 32 bits of entropy. When used in the IP ID generation algorithm, this has the effect of extending the IP ID generation key from 32 bits to 64 bits. However, net_hash_mix() is only used for IP ID generation starting with kernel version 4.1. Therefore, earlier kernels remain with 32-bit key no matter what the net_hash_mix() return value is. This change addresses the issue by explicitly extending the key to 64 bits for kernels older than 4.1. Signed-off-by: Amit Klein <aksecurity@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: fix IPv6 prefix route residueZhiqiang Liu2019-05-021-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | commit e75913c93f7cd5f338ab373c34c93a655bd309cb upstream. Follow those steps: # ip addr add 2001:123::1/32 dev eth0 # ip addr add 2001:123:456::2/64 dev eth0 # ip addr del 2001:123::1/32 dev eth0 # ip addr del 2001:123:456::2/64 dev eth0 and then prefix route of 2001:123::1/32 will still exist. This is because ipv6_prefix_equal in check_cleanup_prefix_route func does not check whether two IPv6 addresses have the same prefix length. If the prefix of one address starts with another shorter address prefix, even though their prefix lengths are different, the return value of ipv6_prefix_equal is true. Here I add a check of whether two addresses have the same prefix to decide whether their prefixes are equal. Fixes: 5b84efecb7d9 ("ipv6 addrconf: don't cleanup prefix route for IFA_F_NOPREFIXROUTE") Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Reported-by: Wenhao Zhang <zhangwenhao8@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()Hangbin Liu2019-05-021-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 173656accaf583698bac3f9e269884ba60d51ef4 upstream. 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 <jishi@redhat.com> Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error") Cc: Oussama Ghorbel <ghorbel@pivasoftware.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: tunnels: fix two use-after-freeEric Dumazet2019-02-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit cbb49697d5512ce9e61b45ce75d3ee43d7ea5524 upstream. xfrm6_policy_check() might have re-allocated skb->head, we need to reload ipv6 header pointer. sysbot reported : BUG: KASAN: use-after-free in __ipv6_addr_type+0x302/0x32f net/ipv6/addrconf_core.c:40 Read of size 4 at addr ffff888191b8cb70 by task syz-executor2/1304 CPU: 0 PID: 1304 Comm: syz-executor2 Not tainted 4.20.0-rc7+ #356 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 __ipv6_addr_type+0x302/0x32f net/ipv6/addrconf_core.c:40 ipv6_addr_type include/net/ipv6.h:403 [inline] ip6_tnl_get_cap+0x27/0x190 net/ipv6/ip6_tunnel.c:727 ip6_tnl_rcv_ctl+0xdb/0x2a0 net/ipv6/ip6_tunnel.c:757 vti6_rcv+0x336/0x8f3 net/ipv6/ip6_vti.c:321 xfrm6_ipcomp_rcv+0x1a5/0x3a0 net/ipv6/xfrm6_protocol.c:132 ip6_protocol_deliver_rcu+0x372/0x1940 net/ipv6/ip6_input.c:394 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:443 IPVS: ftp: loaded support on port[0] = 21 ip6_mc_input+0x514/0x11c0 net/ipv6/ip6_input.c:537 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x115/0x640 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5083 process_backlog+0x24e/0x7a0 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x7fa/0x19b0 net/core/dev.c:6412 __do_softirq+0x308/0xb7e kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 </IRQ> do_softirq.part.14+0x126/0x160 kernel/softirq.c:337 do_softirq+0x19/0x20 kernel/softirq.c:340 netif_rx_ni+0x521/0x860 net/core/dev.c:4569 dev_loopback_xmit+0x287/0x8c0 net/core/dev.c:3576 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_finish_output2+0x193a/0x2930 net/ipv6/ip6_output.c:84 ip6_fragment+0x2b06/0x3850 net/ipv6/ip6_output.c:727 ip6_finish_output+0x6b7/0xc50 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x232/0x9d0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0xc5/0x1b0 net/ipv6/output_core.c:176 ip6_send_skb+0xbc/0x340 net/ipv6/ip6_output.c:1727 ip6_push_pending_frames+0xc5/0xf0 net/ipv6/ip6_output.c:1747 rawv6_push_pending_frames net/ipv6/raw.c:615 [inline] rawv6_sendmsg+0x3a3e/0x4b40 net/ipv6/raw.c:945 kobject: 'queues' (0000000089e6eea2): kobject_add_internal: parent: 'tunl0', set: '<NULL>' kobject: 'queues' (0000000089e6eea2): kobject_uevent_env inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 kobject: 'queues' (0000000089e6eea2): kobject_uevent_env: filter function caused the event to drop! sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 sock_write_iter+0x35e/0x5c0 net/socket.c:900 call_write_iter include/linux/fs.h:1857 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x6b8/0x9f0 fs/read_write.c:487 kobject: 'rx-0' (00000000e2d902d9): kobject_add_internal: parent: 'queues', set: 'queues' kobject: 'rx-0' (00000000e2d902d9): kobject_uevent_env vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 kobject: 'rx-0' (00000000e2d902d9): fill_kobj_path: path = '/devices/virtual/net/tunl0/queues/rx-0' __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 kobject: 'tx-0' (00000000443b70ac): kobject_add_internal: parent: 'queues', set: 'queues' entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457669 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f9bd200bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457669 RDX: 000000000000058f RSI: 00000000200033c0 RDI: 0000000000000003 kobject: 'tx-0' (00000000443b70ac): kobject_uevent_env RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9bd200c6d4 R13: 00000000004c2dcc R14: 00000000004da398 R15: 00000000ffffffff Allocated by task 1304: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3684 [inline] __kmalloc_node_track_caller+0x50/0x70 mm/slab.c:3698 __kmalloc_reserve.isra.41+0x41/0xe0 net/core/skbuff.c:140 __alloc_skb+0x155/0x760 net/core/skbuff.c:208 kobject: 'tx-0' (00000000443b70ac): fill_kobj_path: path = '/devices/virtual/net/tunl0/queues/tx-0' alloc_skb include/linux/skbuff.h:1011 [inline] __ip6_append_data.isra.49+0x2f1a/0x3f50 net/ipv6/ip6_output.c:1450 ip6_append_data+0x1bc/0x2d0 net/ipv6/ip6_output.c:1619 rawv6_sendmsg+0x15ab/0x4b40 net/ipv6/raw.c:938 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe kobject: 'gre0' (00000000cb1b2d7b): kobject_add_internal: parent: 'net', set: 'devices' Freed by task 1304: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 skb_free_head+0x93/0xb0 net/core/skbuff.c:553 pskb_expand_head+0x3b2/0x10d0 net/core/skbuff.c:1498 __pskb_pull_tail+0x156/0x18a0 net/core/skbuff.c:1896 pskb_may_pull include/linux/skbuff.h:2188 [inline] _decode_session6+0xd11/0x14d0 net/ipv6/xfrm6_policy.c:150 __xfrm_decode_session+0x71/0x140 net/xfrm/xfrm_policy.c:3272 kobject: 'gre0' (00000000cb1b2d7b): kobject_uevent_env __xfrm_policy_check+0x380/0x2c40 net/xfrm/xfrm_policy.c:3322 __xfrm_policy_check2 include/net/xfrm.h:1170 [inline] xfrm_policy_check include/net/xfrm.h:1175 [inline] xfrm6_policy_check include/net/xfrm.h:1185 [inline] vti6_rcv+0x4bd/0x8f3 net/ipv6/ip6_vti.c:316 xfrm6_ipcomp_rcv+0x1a5/0x3a0 net/ipv6/xfrm6_protocol.c:132 ip6_protocol_deliver_rcu+0x372/0x1940 net/ipv6/ip6_input.c:394 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434 NF_HOOK include/linux/netfilter.h:289 [inline] ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:443 ip6_mc_input+0x514/0x11c0 net/ipv6/ip6_input.c:537 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0x115/0x640 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5083 process_backlog+0x24e/0x7a0 net/core/dev.c:5923 kobject: 'gre0' (00000000cb1b2d7b): fill_kobj_path: path = '/devices/virtual/net/gre0' napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x7fa/0x19b0 net/core/dev.c:6412 __do_softirq+0x308/0xb7e kernel/softirq.c:292 The buggy address belongs to the object at ffff888191b8cac0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 176 bytes inside of 512-byte region [ffff888191b8cac0, ffff888191b8ccc0) The buggy address belongs to the page: page:ffffea000646e300 count:1 mapcount:0 mapping:ffff8881da800940 index:0x0 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea0006eaaa48 ffffea00065356c8 ffff8881da800940 raw: 0000000000000000 ffff888191b8c0c0 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected kobject: 'queues' (000000005fd6226e): kobject_add_internal: parent: 'gre0', set: '<NULL>' Memory state around the buggy address: ffff888191b8ca00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888191b8ca80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff888191b8cb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888191b8cb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888191b8cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 0d3c703a9d17 ("ipv6: Cleanup IPv6 tunnel receive path") Fixes: ed1efb2aefbb ("ipv6: Add support for IPsec virtual tunnel interfaces") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: Drop change in ipxip6_rcv()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6/ndisc: Preserve IPv6 control buffer if protocol error handlers are calledStefano Brivio2019-02-111-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ee1abcf689353f36d9322231b4320926096bdee0 upstream. Commit a61bbcf28a8c ("[NET]: Store skb->timestamp as offset to a base timestamp") introduces a neighbour control buffer and zeroes it out in ndisc_rcv(), as ndisc_recv_ns() uses it. Commit f2776ff04722 ("[IPV6]: Fix address/interface handling in UDP and DCCP, according to the scoping architecture.") introduces the usage of the IPv6 control buffer in protocol error handlers (e.g. inet6_iif() in present-day __udp6_lib_err()). Now, with commit b94f1c0904da ("ipv6: Use icmpv6_notify() to propagate redirect, instead of rt6_redirect()."), we call protocol error handlers from ndisc_redirect_rcv(), after the control buffer is already stolen and some parts are already zeroed out. This implies that inet6_iif() on this path will always return zero. This gives unexpected results on UDP socket lookup in __udp6_lib_err(), as we might actually need to match sockets for a given interface. Instead of always claiming the control buffer in ndisc_rcv(), do that only when needed. Fixes: b94f1c0904da ("ipv6: Use icmpv6_notify() to propagate redirect, instead of rt6_redirect().") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: Fix another sparse warning on rt6i_nodeBen Hutchings2019-02-111-3/+3
| | | | | | | | | | | | Commit 0933273ce750 "ipv6: fix sparse warning on rt6i_node" fixed some sparse warnings in ip6_fib.c, but introduced a new one in fib6_update_sernum() (which was removed before the corresponding upstream commit). fib6_update_sernum() is called in a RCU read-side section, so use rcu_dereference() to read rt6_info::rt6i_node. Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net/ipv6: Fix index counter for unicast addresses in in6_dump_addrsDavid Ahern2018-12-161-2/+4
| | | | | | | | | | | | | | | | | | | | commit 4ba4c566ba8448a05e6257e0b98a21f1a0d55315 upstream. The loop wants to skip previously dumped addresses, so loops until current index >= saved index. If the message fills it wants to save the index for the next address to dump - ie., the one that did not fit in the current message. Currently, it is incrementing the index counter before comparing to the saved index, and then the saved index is off by 1 - it assumes the current address is going to fit in the message. Change the index handling to increment only after a succesful dump. Fixes: 502a2ffd7376a ("ipv6: convert idev_list to list macros") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: take rcu lock in rawv6_send_hdrinc()Wei Wang2018-12-161-9/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a688caa34beb2fd2a92f1b6d33e40cde433ba160 upstream. In rawv6_send_hdrinc(), in order to avoid an extra dst_hold(), we directly assign the dst to skb and set passed in dst to NULL to avoid double free. However, in error case, we free skb and then do stats update with the dst pointer passed in. This causes use-after-free on the dst. Fix it by taking rcu read lock right before dst could get released to make sure dst does not get freed until the stats update is done. Note: we don't have this issue in ipv4 cause dst is not used for stats update in v4. Syzkaller reported following crash: BUG: KASAN: use-after-free in rawv6_send_hdrinc net/ipv6/raw.c:692 [inline] BUG: KASAN: use-after-free in rawv6_sendmsg+0x4421/0x4630 net/ipv6/raw.c:921 Read of size 8 at addr ffff8801d95ba730 by task syz-executor0/32088 CPU: 1 PID: 32088 Comm: syz-executor0 Not tainted 4.19.0-rc2+ #93 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 rawv6_send_hdrinc net/ipv6/raw.c:692 [inline] rawv6_sendmsg+0x4421/0x4630 net/ipv6/raw.c:921 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2114 __sys_sendmsg+0x11d/0x280 net/socket.c:2152 __do_sys_sendmsg net/socket.c:2161 [inline] __se_sys_sendmsg net/socket.c:2159 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457099 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f83756edc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f83756ee6d4 RCX: 0000000000457099 RDX: 0000000000000000 RSI: 0000000020003840 RDI: 0000000000000004 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d4b30 R14: 00000000004c90b1 R15: 0000000000000000 Allocated by task 32088: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554 dst_alloc+0xbb/0x1d0 net/core/dst.c:105 ip6_dst_alloc+0x35/0xa0 net/ipv6/route.c:353 ip6_rt_cache_alloc+0x247/0x7b0 net/ipv6/route.c:1186 ip6_pol_route+0x8f8/0xd90 net/ipv6/route.c:1895 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2093 fib6_rule_lookup+0x277/0x860 net/ipv6/fib6_rules.c:122 ip6_route_output_flags+0x2c5/0x350 net/ipv6/route.c:2121 ip6_route_output include/net/ip6_route.h:88 [inline] ip6_dst_lookup_tail+0xe27/0x1d60 net/ipv6/ip6_output.c:951 ip6_dst_lookup_flow+0xc8/0x270 net/ipv6/ip6_output.c:1079 rawv6_sendmsg+0x12d9/0x4630 net/ipv6/raw.c:905 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2114 __sys_sendmsg+0x11d/0x280 net/socket.c:2152 __do_sys_sendmsg net/socket.c:2161 [inline] __se_sys_sendmsg net/socket.c:2159 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 5356: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3756 dst_destroy+0x267/0x3c0 net/core/dst.c:141 dst_destroy_rcu+0x16/0x19 net/core/dst.c:154 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2576 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2880 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2847 [inline] rcu_process_callbacks+0xf23/0x2670 kernel/rcu/tree.c:2864 __do_softirq+0x30b/0xad8 kernel/softirq.c:292 Fixes: 1789a640f556 ("raw: avoid two atomics in xmit") Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - We don't set tstamp here - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: Compute net once in raw6_send_hdrincEric W. Biederman2018-12-161-2/+3
| | | | | | | | | commit adb28c9d3371c845c7a28bfd4fb163aca0d0dc37 upstream. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip6_tunnel: be careful when accessing the inner headerPaolo Abeni2018-12-161-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 76c0ddd8c3a683f6e2c6e60e11dc1a1558caf4bc upstream. the ip6 tunnel xmit ndo assumes that the processed skb always contains an ip[v6] header, but syzbot has found a way to send frames that fall short of this assumption, leading to the following splat: BUG: KMSAN: uninit-value in ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1307 [inline] BUG: KMSAN: uninit-value in ip6_tnl_start_xmit+0x7d2/0x1ef0 net/ipv6/ip6_tunnel.c:1390 CPU: 0 PID: 4504 Comm: syz-executor558 Not tainted 4.16.0+ #87 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+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1307 [inline] ip6_tnl_start_xmit+0x7d2/0x1ef0 net/ipv6/ip6_tunnel.c:1390 __netdev_start_xmit include/linux/netdevice.h:4066 [inline] netdev_start_xmit include/linux/netdevice.h:4075 [inline] xmit_one net/core/dev.c:3026 [inline] dev_hard_start_xmit+0x5f1/0xc70 net/core/dev.c:3042 __dev_queue_xmit+0x27ee/0x3520 net/core/dev.c:3557 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3590 packet_snd net/packet/af_packet.c:2944 [inline] packet_sendmsg+0x7c70/0x8a30 net/packet/af_packet.c:2969 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmmsg+0x42d/0x800 net/socket.c:2136 SYSC_sendmmsg+0xc4/0x110 net/socket.c:2167 SyS_sendmmsg+0x63/0x90 net/socket.c:2162 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x441819 RSP: 002b:00007ffe58ee8268 EFLAGS: 00000213 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441819 RDX: 0000000000000002 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00000000006cd018 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000402510 R13: 00000000004025a0 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] alloc_skb_with_frags+0x1d4/0xb20 net/core/skbuff.c:5234 sock_alloc_send_pskb+0xb56/0x1190 net/core/sock.c:2085 packet_alloc_skb net/packet/af_packet.c:2803 [inline] packet_snd net/packet/af_packet.c:2894 [inline] packet_sendmsg+0x6454/0x8a30 net/packet/af_packet.c:2969 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmmsg+0x42d/0x800 net/socket.c:2136 SYSC_sendmmsg+0xc4/0x110 net/socket.c:2167 SyS_sendmmsg+0x63/0x90 net/socket.c:2162 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 This change addresses the issue adding the needed check before accessing the inner header. The ipv4 side of the issue is apparently there since the ipv4 over ipv6 initial support, and the ipv6 side predates git history. Fixes: c4d3efafcc93 ("[IPV6] IP6TUNNEL: Add support to IPv4 over IPv6 tunnel.") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+3fde91d4d394747d6db4@syzkaller.appspotmail.com Tested-by: Alexander Potapenko <glider@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: fix possible use-after-free in ip6_xmit()Eric Dumazet2018-12-161-1/+2
| | | | | | | | | | | | | | | | | commit bbd6528d28c1b8e80832b3b018ec402b6f5c3215 upstream. In the unlikely case ip6_xmit() has to call skb_realloc_headroom(), we need to call skb_set_owner_w() before consuming original skb, otherwise we risk a use-after-free. Bring IPv6 in line with what we do in IPv4 to fix this. Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm6: call kfree_skb when skb is toobigThadeu Lima de Souza Cascardo2018-12-161-0/+2
| | | | | | | | | | | | | | | | | | | | | commit 215ab0f021c9fea3c18b75e7d522400ee6a49990 upstream. After commit d6990976af7c5d8f55903bfb4289b6fb030bf754 ("vti6: fix PMTU caching and reporting on xmit"), some too big skbs might be potentially passed down to __xfrm6_output, causing it to fail to transmit but not free the skb, causing a leak of skb, and consequentially a leak of dst references. After running pmtu.sh, that shows as failure to unregister devices in a namespace: [ 311.397671] unregister_netdevice: waiting for veth_b to become free. Usage count = 1 The fix is to call kfree_skb in case of transmit failures. Fixes: dd767856a36e ("xfrm6: Don't call icmpv6_send on local error") Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: fix cleanup ordering for pingv6 registrationSabrina Dubroca2018-12-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a03dc36bdca6b614651fedfcd8559cf914d2d21d upstream. Commit 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.") contains an error in the cleanup path of inet6_init(): when proto_register(&pingv6_prot, 1) fails, we try to unregister &pingv6_prot. When rawv6_init() fails, we skip unregistering &pingv6_prot. Example of panic (triggered by faking a failure of proto_register(&pingv6_prot, 1)): general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI [...] RIP: 0010:__list_del_entry_valid+0x79/0x160 [...] Call Trace: proto_unregister+0xbb/0x550 ? trace_preempt_on+0x6f0/0x6f0 ? sock_no_shutdown+0x10/0x10 inet6_init+0x153/0x1b8 Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* multicast: do not restore deleted record source filter mode to new oneHangbin Liu2018-11-201-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 08d3ffcc0cfaba36f6b86fd568cc3bc773061fa6 upstream. There are two scenarios that we will restore deleted records. The first is when device down and up(or unmap/remap). In this scenario the new filter mode is same with previous one. Because we get it from in_dev->mc_list and we do not touch it during device down and up. The other scenario is when a new socket join a group which was just delete and not finish sending status reports. In this scenario, we should use the current filter mode instead of restore old one. Here are 4 cases in total. old_socket new_socket before_fix after_fix IN(A) IN(A) ALLOW(A) ALLOW(A) IN(A) EX( ) TO_IN( ) TO_EX( ) EX( ) IN(A) TO_EX( ) ALLOW(A) EX( ) EX( ) TO_EX( ) TO_EX( ) Fixes: 24803f38a5c0b (igmp: do not remove igmp souce list info when set link down) Fixes: 1666d49e1d416 (mld: do not remove mld souce list info when set link down) Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: mcast: fix unsolicited report interval after receiving querysHangbin Liu2018-11-201-3/+6
| | | | | | | | | | | | | | | | | commit 6c6da92808442908287fae8ebb0ca041a52469f4 upstream. After recieving MLD querys, we update idev->mc_maxdelay with max_delay from query header. This make the later unsolicited reports have the same interval with mc_maxdelay, which means we may send unsolicited reports with long interval time instead of default configured interval time. Also as we will not call ipv6_mc_reset() after device up. This issue will be there even after leave the group and join other groups. Fixes: fc4eba58b4c14 ("ipv6: make unsolicited report intervals configurable for mld") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* netfilter: ipv6: nf_defrag: reduce struct net memory wasteEric Dumazet2018-11-201-3/+3
| | | | | | | | | | | | | | | | | | | commit 9ce7bc036ae4cfe3393232c86e9e1fea2153c237 upstream. It is a waste of memory to use a full "struct netns_sysctl_ipv6" while only one pointer is really used, considering netns_sysctl_ipv6 keeps growing. Also, since "struct netns_frags" has cache line alignment, it is better to move the frags_hdr pointer outside, otherwise we spend a full cache line for this pointer. This saves 192 bytes of memory per netns. Fixes: c038a767cd69 ("ipv6: add a new namespace for nf_conntrack_reasm") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeedsSabrina Dubroca2018-11-201-1/+2
| | | | | | | | | | | | | | | | | commit 848235edb5c93ed086700584c8ff64f6d7fc778d upstream. Currently, raw6_sk(sk)->ip6mr_table is set unconditionally during ip6_mroute_setsockopt(MRT6_TABLE). A subsequent attempt at the same setsockopt will fail with -ENOENT, since we haven't actually created that table. A similar fix for ipv4 was included in commit 5e1859fbcc3c ("ipv4: ipmr: various fixes and cleanups"). Fixes: d1db275dd3f6 ("ipv6: ip6mr: support multiple tables") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* net: test tailroom before appending to linear skbWillem de Bruijn2018-10-211-1/+2
| | | | | | | | | | | | | | | | | | | | | commit 113f99c3358564a0647d444c2ae34e8b1abfd5b9 upstream. Device features may change during transmission. In particular with corking, a device may toggle scatter-gather in between allocating and writing to an skb. Do not unconditionally assume that !NETIF_F_SG at write time implies that the same held at alloc time and thus the skb has sufficient tailroom. This issue predates git history. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm6: avoid potential infinite loop in _decode_session6()Eric Dumazet2018-10-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d9f92772e8ec388d070752ee8f187ef8fa18621f upstream. syzbot found a way to trigger an infinitie loop by overflowing @offset variable that has been forced to use u16 for some very obscure reason in the past. We probably want to look at NEXTHDR_FRAGMENT handling which looks wrong, in a separate patch. In net-next, we shall try to use skb_header_pointer() instead of pskb_may_pull(). watchdog: BUG: soft lockup - CPU#1 stuck for 134s! [syz-executor738:4553] Modules linked in: irq event stamp: 13885653 hardirqs last enabled at (13885652): [<ffffffff878009d5>] restore_regs_and_return_to_kernel+0x0/0x2b hardirqs last disabled at (13885653): [<ffffffff87800905>] interrupt_entry+0xb5/0xf0 arch/x86/entry/entry_64.S:625 softirqs last enabled at (13614028): [<ffffffff84df0809>] tun_napi_alloc_frags drivers/net/tun.c:1478 [inline] softirqs last enabled at (13614028): [<ffffffff84df0809>] tun_get_user+0x1dd9/0x4290 drivers/net/tun.c:1825 softirqs last disabled at (13614032): [<ffffffff84df1b6f>] tun_get_user+0x313f/0x4290 drivers/net/tun.c:1942 CPU: 1 PID: 4553 Comm: syz-executor738 Not tainted 4.17.0-rc3+ #40 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode kernel/kcov.c:67 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x20/0x50 kernel/kcov.c:101 RSP: 0018:ffff8801d8cfe250 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffff8801d88a8080 RBX: ffff8801d7389e40 RCX: 0000000000000006 RDX: 0000000000000000 RSI: ffffffff868da4ad RDI: ffff8801c8a53277 RBP: ffff8801d8cfe250 R08: ffff8801d88a8080 R09: ffff8801d8cfe3e8 R10: ffffed003b19fc87 R11: ffff8801d8cfe43f R12: ffff8801c8a5327f R13: 0000000000000000 R14: ffff8801c8a4e5fe R15: ffff8801d8cfe3e8 FS: 0000000000d88940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001acab3000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: _decode_session6+0xc1d/0x14f0 net/ipv6/xfrm6_policy.c:150 __xfrm_decode_session+0x71/0x140 net/xfrm/xfrm_policy.c:2368 xfrm_decode_session_reverse include/net/xfrm.h:1213 [inline] icmpv6_route_lookup+0x395/0x6e0 net/ipv6/icmp.c:372 icmp6_send+0x1982/0x2da0 net/ipv6/icmp.c:551 icmpv6_send+0x17a/0x300 net/ipv6/ip6_icmp.c:43 ip6_input_finish+0x14e1/0x1a30 net/ipv6/ip6_input.c:305 NF_HOOK include/linux/netfilter.h:288 [inline] ip6_input+0xe1/0x5e0 net/ipv6/ip6_input.c:327 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x29c/0xa10 net/ipv6/ip6_input.c:71 NF_HOOK include/linux/netfilter.h:288 [inline] ipv6_rcv+0xeb8/0x2040 net/ipv6/ip6_input.c:208 __netif_receive_skb_core+0x2468/0x3650 net/core/dev.c:4646 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:4711 netif_receive_skb_internal+0x126/0x7b0 net/core/dev.c:4785 napi_frags_finish net/core/dev.c:5226 [inline] napi_gro_frags+0x631/0xc40 net/core/dev.c:5299 tun_get_user+0x3168/0x4290 drivers/net/tun.c:1951 tun_chr_write_iter+0xb9/0x154 drivers/net/tun.c:1996 call_write_iter include/linux/fs.h:1784 [inline] do_iter_readv_writev+0x859/0xa50 fs/read_write.c:680 do_iter_write+0x185/0x5f0 fs/read_write.c:959 vfs_writev+0x1c7/0x330 fs/read_write.c:1004 do_writev+0x112/0x2f0 fs/read_write.c:1039 __do_sys_writev fs/read_write.c:1112 [inline] __se_sys_writev fs/read_write.c:1109 [inline] __x64_sys_writev+0x75/0xb0 fs/read_write.c:1109 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reported-by: syzbot+0053c8...@syzkaller.appspotmail.com Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: add RTA_TABLE and RTA_PREFSRC to rtm_ipv6_policyEric Dumazet2018-10-211-0/+2
| | | | | | | | | | | | | | | | | | commit aa8f8778493c85fff480cdf8b349b1e1dcb5f243 upstream. KMSAN reported use of uninit-value that I tracked to lack of proper size check on RTA_TABLE attribute. I also believe RTA_PREFSRC lacks a similar check. Fixes: 86872cb57925 ("[IPv6] route: FIB6 configuration using struct fib6_config") Fixes: c3968a857a6b ("ipv6: RTA_PREFSRC support for ipv6 route source address selection") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* vti6: better validate user provided tunnel namesEric Dumazet2018-10-211-2/+5
| | | | | | | | | | | | | commit 537b361fbcbcc3cd6fe2bb47069fd292b9256d16 upstream. Use valid_name() to make sure user does not provide illegal device name. Fixes: ed1efb2aefbb ("ipv6: Add support for IPsec virtual tunnel interfaces") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip6_tunnel: better validate user provided tunnel namesEric Dumazet2018-10-211-3/+5
| | | | | | | | | | | | | | | commit db7a65e3ab78e5b1c4b17c0870ebee35a4ee3257 upstream. Use valid_name() to make sure user does not provide illegal device name. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - Don't touch err as ip6_tnl_create() does not return an error code - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip6_gre: better validate user provided tunnel namesEric Dumazet2018-10-211-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5f42df013b8bc1b6511af7a04bf93b014884ae2a upstream. 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 ip6gre_tunnel_locate+0x334/0x860 net/ipv6/ip6_gre.c:339 Write of size 20 at addr ffff8801afb9f7b8 by task syzkaller851048/4466 CPU: 1 PID: 4466 Comm: syzkaller851048 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] ip6gre_tunnel_locate+0x334/0x860 net/ipv6/ip6_gre.c:339 ip6gre_tunnel_ioctl+0x69d/0x12e0 net/ipv6/ip6_gre.c:1195 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: c12b395a4664 ("gre: Support GRE over IPv6") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: sit: better validate user provided tunnel namesEric Dumazet2018-10-211-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b95211e066fc3494b7c115060b2297b4ba21f025 upstream. 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 <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ipv6: the entire IPv6 header chain must fit the first fragmentPaolo Abeni2018-06-161-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 10b8a3de603df7b96004179b1b33b1708c76d144 upstream. While building ipv6 datagram we currently allow arbitrary large extheaders, even beyond pmtu size. The syzbot has found a way to exploit the above to trigger the following splat: kernel BUG at ./include/linux/skbuff.h:2073! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 4230 Comm: syzkaller672661 Not tainted 4.16.0-rc2+ #326 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__skb_pull include/linux/skbuff.h:2073 [inline] RIP: 0010:__ip6_make_skb+0x1ac8/0x2190 net/ipv6/ip6_output.c:1636 RSP: 0018:ffff8801bc18f0f0 EFLAGS: 00010293 RAX: ffff8801b17400c0 RBX: 0000000000000738 RCX: ffffffff84f01828 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801b415ac18 RBP: ffff8801bc18f360 R08: ffff8801b4576844 R09: 0000000000000000 R10: ffff8801bc18f380 R11: ffffed00367aee4e R12: 00000000000000d6 R13: ffff8801b415a740 R14: dffffc0000000000 R15: ffff8801b45767c0 FS: 0000000001535880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000b000 CR3: 00000001b4123001 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip6_finish_skb include/net/ipv6.h:969 [inline] udp_v6_push_pending_frames+0x269/0x3b0 net/ipv6/udp.c:1073 udpv6_sendmsg+0x2a96/0x3400 net/ipv6/udp.c:1343 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 ___sys_sendmsg+0x320/0x8b0 net/socket.c:2046 __sys_sendmmsg+0x1ee/0x620 net/socket.c:2136 SYSC_sendmmsg net/socket.c:2167 [inline] SyS_sendmmsg+0x35/0x60 net/socket.c:2162 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4404c9 RSP: 002b:00007ffdce35f948 EFLAGS: 00000217 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004404c9 RDX: 0000000000000003 RSI: 0000000020001f00 RDI: 0000000000000003 RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 0000000020000080 R11: 0000000000000217 R12: 0000000000401df0 R13: 0000000000401e80 R14: 0000000000000000 R15: 0000000000000000 Code: ff e8 1d 5e b9 fc e9 15 e9 ff ff e8 13 5e b9 fc e9 44 e8 ff ff e8 29 5e b9 fc e9 c0 e6 ff ff e8 3f f3 80 fc 0f 0b e8 38 f3 80 fc <0f> 0b 49 8d 87 80 00 00 00 4d 8d 87 84 00 00 00 48 89 85 20 fe RIP: __skb_pull include/linux/skbuff.h:2073 [inline] RSP: ffff8801bc18f0f0 RIP: __ip6_make_skb+0x1ac8/0x2190 net/ipv6/ip6_output.c:1636 RSP: ffff8801bc18f0f0 As stated by RFC 7112 section 5: When a host fragments an IPv6 datagram, it MUST include the entire IPv6 Header Chain in the First Fragment. So this patch addresses the issue dropping datagrams with excessive extheader length. It also updates the error path to report to the calling socket nonnegative pmtu values. The issue apparently predates git history. v1 -> v2: cleanup error path, as per Eric's suggestion Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+91e6f9932ff122fa4410@syzkaller.appspotmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: Adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* netfilter: ipv6: fix use-after-free Write in nf_nat_ipv6_manip_pktFlorian Westphal2018-06-161-0/+4
| | | | | | | | | | | | | commit b078556aecd791b0e5cb3a59f4c3a14273b52121 upstream. l4proto->manip_pkt() can cause reallocation of skb head so pointer to the ipv6 header must be reloaded. Reported-and-tested-by: <syzbot+10005f4292fc9cc89de7@syzkaller.appspotmail.com> Fixes: 58a317f1061c89 ("netfilter: ipv6: add IPv6 NAT support") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* udplite: fix partial checksum initializationAlexey Kodanev2018-06-161-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 15f35d49c93f4fa9875235e7bf3e3783d2dd7a1b upstream. Since UDP-Lite is always using checksum, the following path is triggered when calculating pseudo header for it: udp4_csum_init() or udp6_csum_init() skb_checksum_init_zero_check() __skb_checksum_validate_complete() The problem can appear if skb->len is less than CHECKSUM_BREAK. In this particular case __skb_checksum_validate_complete() also invokes __skb_checksum_complete(skb). If UDP-Lite is using partial checksum that covers only part of a packet, the function will return bad checksum and the packet will be dropped. It can be fixed if we skip skb_checksum_init_zero_check() and only set the required pseudo header checksum for UDP-Lite with partial checksum before udp4_csum_init()/udp6_csum_init() functions return. Fixes: ed70fcfcee95 ("net: Call skb_checksum_init in IPv4") Fixes: e4f45b7f40bd ("net: Call skb_checksum_init in IPv6") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* netfilter: drop outermost socket lock in getsockopt()Paolo Abeni2018-06-161-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 01ea306f2ac2baff98d472da719193e738759d93 upstream. The Syzbot reported a possible deadlock in the netfilter area caused by rtnl lock, xt lock and socket lock being acquired with a different order on different code paths, leading to the following backtrace: Reviewed-by: Xin Long <lucien.xin@gmail.com> ====================================================== WARNING: possible circular locking dependency detected 4.15.0+ #301 Not tainted ------------------------------------------------------ syzkaller233489/4179 is trying to acquire lock: (rtnl_mutex){+.+.}, at: [<0000000048e996fd>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 but task is already holding lock: (&xt[i].mutex){+.+.}, at: [<00000000328553a2>] xt_find_table_lock+0x3e/0x3e0 net/netfilter/x_tables.c:1041 which lock already depends on the new lock. === Since commit 3f34cfae1230 ("netfilter: on sockopt() acquire sock lock only in the required scope"), we already acquire the socket lock in the innermost scope, where needed. In such commit I forgot to remove the outer-most socket lock from the getsockopt() path, this commit addresses the issues dropping it now. v1 -> v2: fix bad subj, added relavant 'fixes' tag Fixes: 22265a5c3c10 ("netfilter: xt_TEE: resolve oif using netdevice notifiers") Fixes: 202f59afd441 ("netfilter: ipt_CLUSTERIP: do not hold dev") Fixes: 3f34cfae1230 ("netfilter: on sockopt() acquire sock lock only in the required scope") Reported-by: syzbot+ddde1c7b7ff7442d7f2d@syzkaller.appspotmail.com Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* netfilter: on sockopt() acquire sock lock only in the required scopePaolo Abeni2018-06-162-18/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3f34cfae1238848fd53f25e5c8fd59da57901f4b upstream. Syzbot reported several deadlocks in the netfilter area caused by rtnl lock and socket lock being acquired with a different order on different code paths, leading to backtraces like the following one: ====================================================== WARNING: possible circular locking dependency detected 4.15.0-rc9+ #212 Not tainted ------------------------------------------------------ syzkaller041579/3682 is trying to acquire lock: (sk_lock-AF_INET6){+.+.}, at: [<000000008775e4dd>] lock_sock include/net/sock.h:1463 [inline] (sk_lock-AF_INET6){+.+.}, at: [<000000008775e4dd>] do_ipv6_setsockopt.isra.8+0x3c5/0x39d0 net/ipv6/ipv6_sockglue.c:167 but task is already holding lock: (rtnl_mutex){+.+.}, at: [<000000004342eaa9>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 register_netdevice_notifier+0xad/0x860 net/core/dev.c:1607 tee_tg_check+0x1a0/0x280 net/netfilter/xt_TEE.c:106 xt_check_target+0x22c/0x7d0 net/netfilter/x_tables.c:845 check_target net/ipv6/netfilter/ip6_tables.c:538 [inline] find_check_entry.isra.7+0x935/0xcf0 net/ipv6/netfilter/ip6_tables.c:580 translate_table+0xf52/0x1690 net/ipv6/netfilter/ip6_tables.c:749 do_replace net/ipv6/netfilter/ip6_tables.c:1165 [inline] do_ip6t_set_ctl+0x370/0x5f0 net/ipv6/netfilter/ip6_tables.c:1691 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x115/0x150 net/ipv6/ipv6_sockglue.c:928 udpv6_setsockopt+0x45/0x80 net/ipv6/udp.c:1422 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2978 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 entry_SYSCALL_64_fastpath+0x29/0xa0 -> #0 (sk_lock-AF_INET6){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914 lock_sock_nested+0xc2/0x110 net/core/sock.c:2780 lock_sock include/net/sock.h:1463 [inline] do_ipv6_setsockopt.isra.8+0x3c5/0x39d0 net/ipv6/ipv6_sockglue.c:167 ipv6_setsockopt+0xd7/0x150 net/ipv6/ipv6_sockglue.c:922 udpv6_setsockopt+0x45/0x80 net/ipv6/udp.c:1422 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2978 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 entry_SYSCALL_64_fastpath+0x29/0xa0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(sk_lock-AF_INET6); lock(rtnl_mutex); lock(sk_lock-AF_INET6); *** DEADLOCK *** 1 lock held by syzkaller041579/3682: #0: (rtnl_mutex){+.+.}, at: [<000000004342eaa9>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 The problem, as Florian noted, is that nf_setsockopt() is always called with the socket held, even if the lock itself is required only for very tight scopes and only for some operation. This patch addresses the issues moving the lock_sock() call only where really needed, namely in ipv*_getorigdst(), so that nf_setsockopt() does not need anymore to acquire both locks. Fixes: 22265a5c3c10 ("netfilter: xt_TEE: resolve oif using netdevice notifiers") Reported-by: syzbot+a4c2dc980ac1af699b36@syzkaller.appspotmail.com Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm: Return error on unknown encap_type in init_stateHerbert Xu2018-03-031-2/+1
| | | | | | | | | | | | | | | | | | | | commit bcfd09f7837f5240c30fd2f52ee7293516641faa upstream. Currently esp will happily create an xfrm state with an unknown encap type for IPv4, without setting the necessary state parameters. This patch fixes it by returning -EINVAL. There is a similar problem in IPv6 where if the mode is unknown we will skip initialisation while returning zero. However, this is harmless as the mode has already been checked further up the stack. This patch removes this anomaly by aligning the IPv6 behaviour with IPv4 and treating unknown modes (which cannot actually happen) as transport mode. Fixes: 38320c70d282 ("[IPSEC]: Use crypto_aead and authenc in ESP") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* xfrm: Reinject transport-mode packets through taskletHerbert Xu2018-03-031-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit acf568ee859f098279eadf551612f103afdacb4e upstream. This is an old bugbear of mine: https://www.mail-archive.com/netdev@vger.kernel.org/msg03894.html By crafting special packets, it is possible to cause recursion in our kernel when processing transport-mode packets at levels that are only limited by packet size. The easiest one is with DNAT, but an even worse one is where UDP encapsulation is used in which case you just have to insert an UDP encapsulation header in between each level of recursion. This patch avoids this problem by reinjecting tranport-mode packets through a tasklet. Fixes: b05e106698d9 ("[IPV4/6]: Netfilter IPsec input hooks") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> [bwh: Backported to 3.16: - netfilter finish callbacks only receive an sk_buff pointer - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* tcp md5sig: Use skb's saddr when replying to an incoming segmentChristoph Paasch2018-03-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | commit 30791ac41927ebd3e75486f9504b6d2280463bf0 upstream. The MD5-key that belongs to a connection is identified by the peer's IP-address. When we are in tcp_v4(6)_reqsk_send_ack(), we are replying to an incoming segment from tcp_check_req() that failed the seq-number checks. Thus, to find the correct key, we need to use the skb's saddr and not the daddr. This bug seems to have been there since quite a while, but probably got unnoticed because the consequences are not catastrophic. We will call tcp_v4_reqsk_send_ack only to send a challenge-ACK back to the peer, thus the connection doesn't really fail. Fixes: 9501f9722922 ("tcp md5sig: Let the caller pass appropriate key for tcp_v{4,6}_do_calc_md5_hash().") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ip6_gre: only increase err_count for some certain type icmpv6 in ip6gre_errXin Long2018-01-011-4/+7
| | | | | | | | | | | | | | | | commit f8d20b46ce55cf40afb30dcef6d9288f7ef46d9b upstream. The similar fix in patch 'ipip: only increase err_count for some certain type icmp in ipip_err' is needed for ip6gre_err. In Jianlin's case, udp netperf broke even when receiving a TooBig icmpv6 packet. Fixes: c12b395a4664 ("gre: Support GRE over IPv6") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>