<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/ipv6, branch v3.16.67</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>inet: update the IP ID generation algorithm to higher standards.</title>
<updated>2019-05-11T14:22:47+00:00</updated>
<author>
<name>Amit Klein</name>
<email>aksecurity@gmail.com</email>
</author>
<published>2019-04-18T21:07:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b197d3ce585d6777197e0633d71e5af7d98cb35'/>
<id>8b197d3ce585d6777197e0633d71e5af7d98cb35</id>
<content type='text'>
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 &lt;aksecurity@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;aksecurity@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: fix IPv6 prefix route residue</title>
<updated>2019-05-02T20:41:51+00:00</updated>
<author>
<name>Zhiqiang Liu</name>
<email>liuzhiqiang26@huawei.com</email>
</author>
<published>2019-02-11T02:57:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=da93eb476f54e0a3bc922ef4be62b51a720e915e'/>
<id>da93eb476f54e0a3bc922ef4be62b51a720e915e</id>
<content type='text'>
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 &lt;liuzhiqiang26@huawei.com&gt;
Reported-by: Wenhao Zhang &lt;zhangwenhao8@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;liuzhiqiang26@huawei.com&gt;
Reported-by: Wenhao Zhang &lt;zhangwenhao8@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()</title>
<updated>2019-05-02T20:41:49+00:00</updated>
<author>
<name>Hangbin Liu</name>
<email>liuhangbin@gmail.com</email>
</author>
<published>2019-02-07T10:36:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=869b83cb1c076d804679e08065626743d0b91e9d'/>
<id>869b83cb1c076d804679e08065626743d0b91e9d</id>
<content type='text'>
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 &lt;jishi@redhat.com&gt;
Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error")
Cc: Oussama Ghorbel &lt;ghorbel@pivasoftware.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Reviewed-by: Stefano Brivio &lt;sbrivio@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;jishi@redhat.com&gt;
Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error")
Cc: Oussama Ghorbel &lt;ghorbel@pivasoftware.com&gt;
Signed-off-by: Hangbin Liu &lt;liuhangbin@gmail.com&gt;
Reviewed-by: Stefano Brivio &lt;sbrivio@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: tunnels: fix two use-after-free</title>
<updated>2019-02-11T17:54:31+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2018-12-21T15:47:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9b3e976d8e483c1a7590ca0bbf7a73083adaedb2'/>
<id>9b3e976d8e483c1a7590ca0bbf7a73083adaedb2</id>
<content type='text'>
commit cbb49697d5512ce9e61b45ce75d3ee43d7ea5524 upstream.

xfrm6_policy_check() might have re-allocated skb-&gt;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:
 &lt;IRQ&gt;
 __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
 &lt;/IRQ&gt;
 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: '&lt;NULL&gt;'
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 &lt;48&gt; 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: '&lt;NULL&gt;'

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
&gt;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 &lt;edumazet@google.com&gt;
Cc: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: Drop change in ipxip6_rcv()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit cbb49697d5512ce9e61b45ce75d3ee43d7ea5524 upstream.

xfrm6_policy_check() might have re-allocated skb-&gt;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:
 &lt;IRQ&gt;
 __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
 &lt;/IRQ&gt;
 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: '&lt;NULL&gt;'
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 &lt;48&gt; 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: '&lt;NULL&gt;'

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
&gt;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 &lt;edumazet@google.com&gt;
Cc: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: Drop change in ipxip6_rcv()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6/ndisc: Preserve IPv6 control buffer if protocol error handlers are called</title>
<updated>2019-02-11T17:53:42+00:00</updated>
<author>
<name>Stefano Brivio</name>
<email>sbrivio@redhat.com</email>
</author>
<published>2018-10-24T12:37:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a716e82ca67de17ebcef47cabdb266b1ffdf6254'/>
<id>a716e82ca67de17ebcef47cabdb266b1ffdf6254</id>
<content type='text'>
commit ee1abcf689353f36d9322231b4320926096bdee0 upstream.

Commit a61bbcf28a8c ("[NET]: Store skb-&gt;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 &lt;sbrivio@redhat.com&gt;
Reviewed-by: Sabrina Dubroca &lt;sd@queasysnail.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ee1abcf689353f36d9322231b4320926096bdee0 upstream.

Commit a61bbcf28a8c ("[NET]: Store skb-&gt;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 &lt;sbrivio@redhat.com&gt;
Reviewed-by: Sabrina Dubroca &lt;sd@queasysnail.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: Fix another sparse warning on rt6i_node</title>
<updated>2019-02-11T17:53:13+00:00</updated>
<author>
<name>Ben Hutchings</name>
<email>ben@decadent.org.uk</email>
</author>
<published>2019-02-01T02:10:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=254610c85c66d4df64c89873eb6eb9b8461f0ded'/>
<id>254610c85c66d4df64c89873eb6eb9b8461f0ded</id>
<content type='text'>
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 &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/ipv6: Fix index counter for unicast addresses in in6_dump_addrs</title>
<updated>2018-12-16T22:09:43+00:00</updated>
<author>
<name>David Ahern</name>
<email>dsahern@gmail.com</email>
</author>
<published>2018-10-19T17:00:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=52de52ca372090ac6eb8e7d1dc1c33ba49b73d09'/>
<id>52de52ca372090ac6eb8e7d1dc1c33ba49b73d09</id>
<content type='text'>
commit 4ba4c566ba8448a05e6257e0b98a21f1a0d55315 upstream.

The loop wants to skip previously dumped addresses, so loops until
current index &gt;= 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 &lt;dsahern@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4ba4c566ba8448a05e6257e0b98a21f1a0d55315 upstream.

The loop wants to skip previously dumped addresses, so loops until
current index &gt;= 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 &lt;dsahern@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: take rcu lock in rawv6_send_hdrinc()</title>
<updated>2018-12-16T22:09:36+00:00</updated>
<author>
<name>Wei Wang</name>
<email>weiwan@google.com</email>
</author>
<published>2018-10-04T17:12:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9db8f411f90eae46da77865d2bb72ad5fb5721b0'/>
<id>9db8f411f90eae46da77865d2bb72ad5fb5721b0</id>
<content type='text'>
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 &lt;48&gt; 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 &lt;weiwan@google.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16:
 - We don't set tstamp here
 - Adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;48&gt; 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 &lt;weiwan@google.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16:
 - We don't set tstamp here
 - Adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv6: Compute net once in raw6_send_hdrinc</title>
<updated>2018-12-16T22:09:36+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2015-09-16T01:04:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e959a6ac3ecb7be134b49f4b71ecacb43f625d1a'/>
<id>e959a6ac3ecb7be134b49f4b71ecacb43f625d1a</id>
<content type='text'>
commit adb28c9d3371c845c7a28bfd4fb163aca0d0dc37 upstream.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit adb28c9d3371c845c7a28bfd4fb163aca0d0dc37 upstream.

Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ip6_tunnel: be careful when accessing the inner header</title>
<updated>2018-12-16T22:09:21+00:00</updated>
<author>
<name>Paolo Abeni</name>
<email>pabeni@redhat.com</email>
</author>
<published>2018-09-19T13:02:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=07259ac76d2876a26d7223b825fb0cec403932b8'/>
<id>07259ac76d2876a26d7223b825fb0cec403932b8</id>
<content type='text'>
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 &lt;glider@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;glider@google.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
</feed>
