linux.git/net/ipv6/datagram.c, branch v5.6-rc2

net: ipv6: add net argument to ip6_dst_lookup_flow

2019-12-04T20:27:12+00:00

This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow,
as some modules currently pass a net argument without a socket to
ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change
ipv6_stub_impl.ipv6_dst_lookup to take net argument").

Signed-off-by: Sabrina Dubroca 
Signed-off-by: David S. Miller

udp: correct reuseport selection with connected sockets

2019-09-16T07:02:18+00:00

UDP reuseport groups can hold a mix unconnected and connected sockets.
Ensure that connections only receive all traffic to their 4-tuple.

Fast reuseport returns on the first reuseport match on the assumption
that all matches are equal. Only if connections are present, return to
the previous behavior of scoring all sockets.

Record if connections are present and if so (1) treat such connected
sockets as an independent match from the group, (2) only return
2-tuple matches from reuseport and (3) do not return on the first
2-tuple reuseport match to allow for a higher scoring match later.

New field has_conns is set without locks. No other fields in the
bitmap are modified at runtime and the field is only ever set
unconditionally, so an RMW cannot miss a change.

Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection")
Link: http://lkml.kernel.org/r/CA+FuTSfRP09aJNYRt04SS6qj22ViiOEWaWmLAwX0psk8-PGNxw@mail.gmail.com
Signed-off-by: Willem de Bruijn 
Acked-by: Paolo Abeni 
Acked-by: Craig Gallek 
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller

ipv6: fix potential crash in ip6_datagram_dst_update()

2019-07-11T21:43:25+00:00

Willem forgot to change one of the calls to fl6_sock_lookup(),
which can now return an error or NULL.

syzbot reported :

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 31763 Comm: syz-executor.0 Not tainted 5.2.0-rc6+ #63
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ip6_datagram_dst_update+0x559/0xc30 net/ipv6/datagram.c:83
Code: 00 00 e8 ea 29 3f fb 4d 85 f6 0f 84 96 04 00 00 e8 dc 29 3f fb 49 8d 7e 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 16 06 00 00 4d 8b 6e 20 e8 b4 29 3f fb 4c 89 ee
RSP: 0018:ffff88809ba97ae0 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: ffff8880a81254b0 RCX: ffffc90008118000
RDX: 0000000000000003 RSI: ffffffff86319a84 RDI: 000000000000001e
RBP: ffff88809ba97c10 R08: ffff888065e9e700 R09: ffffed1015d26c80
R10: ffffed1015d26c7f R11: ffff8880ae9363fb R12: ffff8880a8124f40
R13: 0000000000000001 R14: fffffffffffffffe R15: ffff88809ba97b40
FS:  00007f38e606a700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000202c0140 CR3: 00000000a026a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __ip6_datagram_connect+0x5e9/0x1390 net/ipv6/datagram.c:246
 ip6_datagram_connect+0x30/0x50 net/ipv6/datagram.c:269
 ip6_datagram_connect_v6_only+0x69/0x90 net/ipv6/datagram.c:281
 inet_dgram_connect+0x14a/0x2d0 net/ipv4/af_inet.c:571
 __sys_connect+0x264/0x330 net/socket.c:1824
 __do_sys_connect net/socket.c:1835 [inline]
 __se_sys_connect net/socket.c:1832 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1832
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4597c9
Code: fd b7 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 b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f38e6069c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004597c9
RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f38e606a6d4
R13: 00000000004bfd07 R14: 00000000004d1838 R15: 00000000ffffffff
Modules linked in:
RIP: 0010:ip6_datagram_dst_update+0x559/0xc30 net/ipv6/datagram.c:83
Code: 00 00 e8 ea 29 3f fb 4d 85 f6 0f 84 96 04 00 00 e8 dc 29 3f fb 49 8d 7e 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 16 06 00 00 4d 8b 6e 20 e8 b4 29 3f fb 4c 89 ee

Fixes: 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist")
Signed-off-by: Eric Dumazet 
Acked-by: Willem de Bruijn 
Reported-by: syzbot 
Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

net: Treat sock->sk_drops as an unsigned int when printing

2019-05-19T17:31:10+00:00

Currently, procfs socket stats format sk_drops as a signed int (%d). For large
values this will cause a negative number to be printed.

We know the drop count can never be a negative so change the format specifier to
%u.

Signed-off-by: Patrick Talbert 
Signed-off-by: David S. Miller

ipv6: fix kernel-infoleak in ipv6_local_error()

2019-01-10T14:36:41+00:00

This patch makes sure the flow label in the IPv6 header
forged in ipv6_local_error() is initialized.

BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
CPU: 1 PID: 24675 Comm: syz-executor1 Not tainted 4.20.0-rc7+ #4
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
 kmsan_internal_check_memory+0x455/0xb00 mm/kmsan/kmsan.c:675
 kmsan_copy_to_user+0xab/0xc0 mm/kmsan/kmsan_hooks.c:601
 _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
 copy_to_user include/linux/uaccess.h:177 [inline]
 move_addr_to_user+0x2e9/0x4f0 net/socket.c:227
 ___sys_recvmsg+0x5d7/0x1140 net/socket.c:2284
 __sys_recvmsg net/socket.c:2327 [inline]
 __do_sys_recvmsg net/socket.c:2337 [inline]
 __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334
 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457ec9
Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8750c06c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9
RDX: 0000000000002000 RSI: 0000000020000400 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8750c076d4
R13: 00000000004c4a60 R14: 00000000004d8140 R15: 00000000ffffffff

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:219 [inline]
 kmsan_internal_chain_origin+0x134/0x230 mm/kmsan/kmsan.c:439
 __msan_chain_origin+0x70/0xe0 mm/kmsan/kmsan_instr.c:200
 ipv6_recv_error+0x1e3f/0x1eb0 net/ipv6/datagram.c:475
 udpv6_recvmsg+0x398/0x2ab0 net/ipv6/udp.c:335
 inet_recvmsg+0x4fb/0x600 net/ipv4/af_inet.c:830
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg+0x1d1/0x230 net/socket.c:801
 ___sys_recvmsg+0x4d5/0x1140 net/socket.c:2278
 __sys_recvmsg net/socket.c:2327 [inline]
 __do_sys_recvmsg net/socket.c:2337 [inline]
 __se_sys_recvmsg+0x2fa/0x450 net/socket.c:2334
 __x64_sys_recvmsg+0x4a/0x70 net/socket.c:2334
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2759 [inline]
 __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:998 [inline]
 ipv6_local_error+0x1a7/0x9e0 net/ipv6/datagram.c:334
 __ip6_append_data+0x129f/0x4fd0 net/ipv6/ip6_output.c:1311
 ip6_make_skb+0x6cc/0xcf0 net/ipv6/ip6_output.c:1775
 udpv6_sendmsg+0x3f8e/0x45d0 net/ipv6/udp.c:1384
 inet_sendmsg+0x54a/0x720 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 4-7 of 28 are uninitialized
Memory access of size 28 starts at ffff8881937bfce0
Data copied to user address 0000000020000000

Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: David S. Miller

ip: on queued skb use skb_header_pointer instead of pskb_may_pull

2019-01-10T14:27:20+00:00

Commit 2efd4fca703a ("ip: in cmsg IP(V6)_ORIGDSTADDR call
pskb_may_pull") avoided a read beyond the end of the skb linear
segment by calling pskb_may_pull.

That function can trigger a BUG_ON in pskb_expand_head if the skb is
shared, which it is when when peeking. It can also return ENOMEM.

Avoid both by switching to safer skb_header_pointer.

Fixes: 2efd4fca703a ("ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull")
Reported-by: syzbot 
Suggested-by: Eric Dumazet 
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller

net: ensure unbound datagram socket to be chosen when not in a VRF

2018-11-08T00:12:38+00:00

Ensure an unbound datagram skt is chosen when not in a VRF. The check
for a device match in compute_score() for UDP must be performed when
there is no device match. For this, a failure is returned when there is
no device match. This ensures that bound sockets are never selected,
even if there is no unbound socket.

Allow IPv6 packets to be sent over a datagram skt bound to a VRF. These
packets are currently blocked, as flowi6_oif was set to that of the
master vrf device, and the ipi6_ifindex is that of the slave device.
Allow these packets to be sent by checking the device with ipi6_ifindex
has the same L3 scope as that of the bound device of the skt, which is
the master vrf device. Note that this check always succeeds if the skt
is unbound.

Even though the right datagram skt is now selected by compute_score(),
a different skt is being returned that is bound to the wrong vrf. The
difference between these and stream sockets is the handling of the skt
option for SO_REUSEPORT. While the handling when adding a skt for reuse
correctly checks that the bound device of the skt is a match, the skts
in the hashslot are already incorrect. So for the same hash, a skt for
the wrong vrf may be selected for the required port. The root cause is
that the skt is immediately placed into a slot when it is created,
but when the skt is then bound using SO_BINDTODEVICE, it remains in the
same slot. The solution is to move the skt to the correct slot by
forcing a rehash.

Signed-off-by: Mike Manning 
Reviewed-by: David Ahern 
Tested-by: David Ahern 
Signed-off-by: David S. Miller

net: add helpers checking if socket can be bound to nonlocal address

2018-08-01T16:50:04+00:00

The construction "net->ipv4.sysctl_ip_nonlocal_bind || inet->freebind
|| inet->transparent" is present three times and its IPv6 counterpart
is also present three times. We introduce two small helpers to
characterize these tests uniformly.

Signed-off-by: Vincent Bernat 
Signed-off-by: David S. Miller

net/ipv6: allow any source address for sendmsg pktinfo with ip_nonlocal_bind

2018-07-29T19:27:13+00:00

When freebind feature is set of an IPv6 socket, any source address can
be used when sending UDP datagrams using IPv6 PKTINFO ancillary
message. Global non-local bind feature was added in commit
35a256fee52c ("ipv6: Nonlocal bind") for IPv6. This commit also allows
IPv6 source address spoofing when non-local bind feature is enabled.

Signed-off-by: Vincent Bernat 
Signed-off-by: David S. Miller