7480 Commits

Author SHA1 Message Date
Kuniyuki Iwashima
eaccca7a0b tcp: Fix data-races around sysctl_tcp_reflect_tos.
[ Upstream commit 870e3a634b6a6cb1543b359007aca73fe6a03ac5 ]

While reading sysctl_tcp_reflect_tos, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: ac8f1710c12b ("tcp: reflect tos value received in SYN to the socket")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:52 +02:00
Taehee Yoo
b01b4f5b45 net: mld: fix reference count leak in mld_{query | report}_work()
[ Upstream commit 3e7d18b9dca388940a19cae30bfc1f76dccd8c28 ]

mld_{query | report}_work() processes queued events.
If there are too many events in the queue, it re-queue a work.
And then, it returns without in6_dev_put().
But if queuing is failed, it should call in6_dev_put(), but it doesn't.
So, a reference count leak would occur.

THREAD0				THREAD1
mld_report_work()
				spin_lock_bh()
				if (!mod_delayed_work())
					in6_dev_hold();
				spin_unlock_bh()
	spin_lock_bh()
	schedule_delayed_work()
	spin_unlock_bh()

Script to reproduce(by Hangbin Liu):
   ip netns add ns1
   ip netns add ns2
   ip netns exec ns1 sysctl -w net.ipv6.conf.all.force_mld_version=1
   ip netns exec ns2 sysctl -w net.ipv6.conf.all.force_mld_version=1

   ip -n ns1 link add veth0 type veth peer name veth0 netns ns2
   ip -n ns1 link set veth0 up
   ip -n ns2 link set veth0 up

   for i in `seq 50`; do
           for j in `seq 100`; do
                   ip -n ns1 addr add 2021:${i}::${j}/64 dev veth0
                   ip -n ns2 addr add 2022:${i}::${j}/64 dev veth0
           done
   done
   modprobe -r veth
   ip -a netns del

splat looks like:
 unregister_netdevice: waiting for veth0 to become free. Usage count = 2
 leaked reference.
  ipv6_add_dev+0x324/0xec0
  addrconf_notify+0x481/0xd10
  raw_notifier_call_chain+0xe3/0x120
  call_netdevice_notifiers+0x106/0x160
  register_netdevice+0x114c/0x16b0
  veth_newlink+0x48b/0xa50 [veth]
  rtnl_newlink+0x11a2/0x1a40
  rtnetlink_rcv_msg+0x63f/0xc00
  netlink_rcv_skb+0x1df/0x3e0
  netlink_unicast+0x5de/0x850
  netlink_sendmsg+0x6c9/0xa90
  ____sys_sendmsg+0x76a/0x780
  __sys_sendmsg+0x27c/0x340
  do_syscall_64+0x43/0x90
  entry_SYSCALL_64_after_hwframe+0x63/0xcd

Tested-by: Hangbin Liu <liuhangbin@gmail.com>
Fixes: f185de28d9ae ("mld: add new workqueues for process mld events")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-03 12:03:51 +02:00
Kuniyuki Iwashima
4845d3ef64 net: ping6: Fix memleak in ipv6_renew_options().
commit e27326009a3d247b831eda38878c777f6f4eb3d1 upstream.

When we close ping6 sockets, some resources are left unfreed because
pingv6_prot is missing sk->sk_prot->destroy().  As reported by
syzbot [0], just three syscalls leak 96 bytes and easily cause OOM.

    struct ipv6_sr_hdr *hdr;
    char data[24] = {0};
    int fd;

    hdr = (struct ipv6_sr_hdr *)data;
    hdr->hdrlen = 2;
    hdr->type = IPV6_SRCRT_TYPE_4;

    fd = socket(AF_INET6, SOCK_DGRAM, NEXTHDR_ICMP);
    setsockopt(fd, IPPROTO_IPV6, IPV6_RTHDR, data, 24);
    close(fd);

To fix memory leaks, let's add a destroy function.

Note the socket() syscall checks if the GID is within the range of
net.ipv4.ping_group_range.  The default value is [1, 0] so that no
GID meets the condition (1 <= GID <= 0).  Thus, the local DoS does
not succeed until we change the default value.  However, at least
Ubuntu/Fedora/RHEL loosen it.

    $ cat /usr/lib/sysctl.d/50-default.conf
    ...
    -net.ipv4.ping_group_range = 0 2147483647

Also, there could be another path reported with these options, and
some of them require CAP_NET_RAW.

  setsockopt
      IPV6_ADDRFORM (inet6_sk(sk)->pktoptions)
      IPV6_RECVPATHMTU (inet6_sk(sk)->rxpmtu)
      IPV6_HOPOPTS (inet6_sk(sk)->opt)
      IPV6_RTHDRDSTOPTS (inet6_sk(sk)->opt)
      IPV6_RTHDR (inet6_sk(sk)->opt)
      IPV6_DSTOPTS (inet6_sk(sk)->opt)
      IPV6_2292PKTOPTIONS (inet6_sk(sk)->opt)

  getsockopt
      IPV6_FLOWLABEL_MGR (inet6_sk(sk)->ipv6_fl_list)

For the record, I left a different splat with syzbot's one.

  unreferenced object 0xffff888006270c60 (size 96):
    comm "repro2", pid 231, jiffies 4294696626 (age 13.118s)
    hex dump (first 32 bytes):
      01 00 00 00 44 00 00 00 00 00 00 00 00 00 00 00  ....D...........
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [<00000000f6bc7ea9>] sock_kmalloc (net/core/sock.c:2564 net/core/sock.c:2554)
      [<000000006d699550>] do_ipv6_setsockopt.constprop.0 (net/ipv6/ipv6_sockglue.c:715)
      [<00000000c3c3b1f5>] ipv6_setsockopt (net/ipv6/ipv6_sockglue.c:1024)
      [<000000007096a025>] __sys_setsockopt (net/socket.c:2254)
      [<000000003a8ff47b>] __x64_sys_setsockopt (net/socket.c:2265 net/socket.c:2262 net/socket.c:2262)
      [<000000007c409dcb>] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
      [<00000000e939c4a9>] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

[0]: https://syzkaller.appspot.com/bug?extid=a8430774139ec3ab7176

Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.")
Reported-by: syzbot+a8430774139ec3ab7176@syzkaller.appspotmail.com
Reported-by: Ayushman Dutta <ayudutta@amazon.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220728012220.46918-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-03 12:03:47 +02:00
Kuniyuki Iwashima
10a9ba97a4 tcp: Fix data-races around sysctl_tcp_syncookies.
[ Upstream commit f2e383b5bb6bbc60a0b94b87b3e49a2b1aefd11e ]

While reading sysctl_tcp_syncookies, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29 17:25:18 +02:00
Kuniyuki Iwashima
01083e3f98 ip: Fix data-races around sysctl_ip_no_pmtu_disc.
[ Upstream commit 0968d2a441bf6afb551fd99e60fa65ed67068963 ]

While reading sysctl_ip_no_pmtu_disc, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-29 17:25:13 +02:00
Andrea Mayer
15e8b6274c seg6: fix skb checksum in SRv6 End.B6 and End.B6.Encaps behaviors
[ Upstream commit f048880fc77058d864aff5c674af7918b30f312a ]

The SRv6 End.B6 and End.B6.Encaps behaviors rely on functions
seg6_do_srh_{encap,inline}() to, respectively: i) encapsulate the
packet within an outer IPv6 header with the specified Segment Routing
Header (SRH); ii) insert the specified SRH directly after the IPv6
header of the packet.

This patch removes the initialization of the IPv6 header payload length
from the input_action_end_b6{_encap}() functions, as it is now handled
properly by seg6_do_srh_{encap,inline}() to avoid corruption of the skb
checksum.

Fixes: 140f04c33bbc ("ipv6: sr: implement several seg6local actions")
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21 21:24:30 +02:00
Andrea Mayer
859081fb60 seg6: fix skb checksum evaluation in SRH encapsulation/insertion
[ Upstream commit df8386d13ea280d55beee1b95f61a59234a3798b ]

Support for SRH encapsulation and insertion was introduced with
commit 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and
injection with lwtunnels"), through the seg6_do_srh_encap() and
seg6_do_srh_inline() functions, respectively.
The former encapsulates the packet in an outer IPv6 header along with
the SRH, while the latter inserts the SRH between the IPv6 header and
the payload. Then, the headers are initialized/updated according to the
operating mode (i.e., encap/inline).
Finally, the skb checksum is calculated to reflect the changes applied
to the headers.

The IPv6 payload length ('payload_len') is not initialized
within seg6_do_srh_{inline,encap}() but is deferred in seg6_do_srh(), i.e.
the caller of seg6_do_srh_{inline,encap}().
However, this operation invalidates the skb checksum, since the
'payload_len' is updated only after the checksum is evaluated.

To solve this issue, the initialization of the IPv6 payload length is
moved from seg6_do_srh() directly into the seg6_do_srh_{inline,encap}()
functions and before the skb checksum update takes place.

Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/all/20220705190727.69d532417be7438b15404ee1@uniroma2.it
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21 21:24:30 +02:00
Kuniyuki Iwashima
0d17723afe nexthop: Fix data-races around nexthop_compat_mode.
[ Upstream commit bdf00bf24bef9be1ca641a6390fd5487873e0d2e ]

While reading nexthop_compat_mode, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 4f80116d3df3 ("net: ipv4: add sysctl for nexthop api compatibility mode")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21 21:24:28 +02:00
Kuniyuki Iwashima
cce955efa0 icmp: Fix data-races around sysctl_icmp_echo_enable_probe.
[ Upstream commit 4a2f7083cc6cb72dade9a63699ca352fad26d1cd ]

While reading sysctl_icmp_echo_enable_probe, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: d329ea5bd884 ("icmp: add response to RFC 8335 PROBE messages")
Fixes: 1fd07f33c3ea ("ipv6: ICMPV6: add response to ICMPV6 RFC 8335 PROBE messages")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21 21:24:26 +02:00
Eric Dumazet
2930ee1a16 ipv6: fix lockdep splat in in6_dump_addrs()
commit 4e43e64d0f1332fcc503babad4dc31aead7131ca upstream.

As reported by syzbot, we should not use rcu_dereference()
when rcu_read_lock() is not held.

WARNING: suspicious RCU usage
5.19.0-rc2-syzkaller #0 Not tainted

net/ipv6/addrconf.c:5175 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor326/3617:
 #0: ffffffff8d5848e8 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xae/0xc20 net/netlink/af_netlink.c:2223

stack backtrace:
CPU: 0 PID: 3617 Comm: syz-executor326 Not tainted 5.19.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 in6_dump_addrs+0x12d1/0x1790 net/ipv6/addrconf.c:5175
 inet6_dump_addr+0x9c1/0xb50 net/ipv6/addrconf.c:5300
 netlink_dump+0x541/0xc20 net/netlink/af_netlink.c:2275
 __netlink_dump_start+0x647/0x900 net/netlink/af_netlink.c:2380
 netlink_dump_start include/linux/netlink.h:245 [inline]
 rtnetlink_rcv_msg+0x73e/0xc90 net/core/rtnetlink.c:6046
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 ____sys_sendmsg+0x6eb/0x810 net/socket.c:2492
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2546
 __sys_sendmsg net/socket.c:2575 [inline]
 __do_sys_sendmsg net/socket.c:2584 [inline]
 __se_sys_sendmsg net/socket.c:2582 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2582
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: 88e2ca308094 ("mld: convert ifmcaddr6 to RCU")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Link: https://lore.kernel.org/r/20220628121248.858695-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:29 +02:00
katrinzhou
d6371303b4 ipv6/sit: fix ipip6_tunnel_get_prl return value
commit adabdd8f6acabc0c3fdbba2e7f5a2edd9c5ef22d upstream.

When kcalloc fails, ipip6_tunnel_get_prl() should return -ENOMEM.
Move the position of label "out" to return correctly.

Addresses-Coverity: ("Unused value")
Fixes: 300aaeeaab5f ("[IPV6] SIT: Add SIOCGETPRL ioctl to get/dump PRL.")
Signed-off-by: katrinzhou <katrinzhou@tencent.com>
Reviewed-by: Eric Dumazet<edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220628035030.1039171-1-zys.zljxml@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:29 +02:00
YueHaibing
c9f8f94d3c net: ipv6: unexport __init-annotated seg6_hmac_net_init()
commit 53ad46169fe2996fe1b623ba6c9c4fa33847876f upstream.

As of commit 5801f064e351 ("net: ipv6: unexport __init-annotated seg6_hmac_init()"),
EXPORT_SYMBOL and __init is a bad combination because the .init.text
section is freed up after the initialization. Hence, modules cannot
use symbols annotated __init. The access to a freed symbol may end up
with kernel panic.

This remove the EXPORT_SYMBOL to fix modpost warning:

WARNING: modpost: vmlinux.o(___ksymtab+seg6_hmac_net_init+0x0): Section mismatch in reference from the variable __ksymtab_seg6_hmac_net_init to the function .init.text:seg6_hmac_net_init()
The symbol seg6_hmac_net_init is exported and annotated __init
Fix this by removing the __init annotation of seg6_hmac_net_init or drop the export.

Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20220628033134.21088-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:26 +02:00
Nicolas Dichtel
159f2454ab ipv6: take care of disable_policy when restoring routes
commit 3b0dc529f56b5f2328244130683210be98f16f7f upstream.

When routes corresponding to addresses are restored by
fixup_permanent_addr(), the dst_nopolicy parameter was not set.
The typical use case is a user that configures an address on a down
interface and then put this interface up.

Let's take care of this flag in addrconf_f6i_alloc(), so that every callers
benefit ont it.

CC: stable@kernel.org
CC: David Forster <dforster@brocade.com>
Fixes: df789fe75206 ("ipv6: Provide ipv6 version of "disable_policy" sysctl")
Reported-by: Siwar Zitouni <siwar.zitouni@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220623120015.32640-1-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:53:23 +02:00
Eric Dumazet
a3b2470399 erspan: do not assume transport header is always set
[ Upstream commit 301bd140ed0b24f0da660874c7e8a47dad8c8222 ]

Rewrite tests in ip6erspan_tunnel_xmit() and
erspan_fb_xmit() to not assume transport header is set.

syzbot reported:

WARNING: CPU: 0 PID: 1350 at include/linux/skbuff.h:2911 skb_transport_header include/linux/skbuff.h:2911 [inline]
WARNING: CPU: 0 PID: 1350 at include/linux/skbuff.h:2911 ip6erspan_tunnel_xmit+0x15af/0x2eb0 net/ipv6/ip6_gre.c:963
Modules linked in:
CPU: 0 PID: 1350 Comm: aoe_tx0 Not tainted 5.19.0-rc2-syzkaller-00160-g274295c6e53f #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:skb_transport_header include/linux/skbuff.h:2911 [inline]
RIP: 0010:ip6erspan_tunnel_xmit+0x15af/0x2eb0 net/ipv6/ip6_gre.c:963
Code: 0f 47 f0 40 88 b5 7f fe ff ff e8 8c 16 4b f9 89 de bf ff ff ff ff e8 a0 12 4b f9 66 83 fb ff 0f 85 1d f1 ff ff e8 71 16 4b f9 <0f> 0b e9 43 f0 ff ff e8 65 16 4b f9 48 8d 85 30 ff ff ff ba 60 00
RSP: 0018:ffffc90005daf910 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 000000000000ffff RCX: 0000000000000000
RDX: ffff88801f032100 RSI: ffffffff882e8d3f RDI: 0000000000000003
RBP: ffffc90005dafab8 R08: 0000000000000003 R09: 000000000000ffff
R10: 000000000000ffff R11: 0000000000000000 R12: ffff888024f21d40
R13: 000000000000a288 R14: 00000000000000b0 R15: ffff888025a2e000
FS: 0000000000000000(0000) GS:ffff88802c800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e425000 CR3: 000000006d099000 CR4: 0000000000152ef0
Call Trace:
<TASK>
__netdev_start_xmit include/linux/netdevice.h:4805 [inline]
netdev_start_xmit include/linux/netdevice.h:4819 [inline]
xmit_one net/core/dev.c:3588 [inline]
dev_hard_start_xmit+0x188/0x880 net/core/dev.c:3604
sch_direct_xmit+0x19f/0xbe0 net/sched/sch_generic.c:342
__dev_xmit_skb net/core/dev.c:3815 [inline]
__dev_queue_xmit+0x14a1/0x3900 net/core/dev.c:4219
dev_queue_xmit include/linux/netdevice.h:2994 [inline]
tx+0x6a/0xc0 drivers/block/aoe/aoenet.c:63
kthread+0x1e7/0x3b0 drivers/block/aoe/aoecmd.c:1229
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
</TASK>

Fixes: d5db21a3e697 ("erspan: auto detect truncated ipv6 packets.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-29 09:03:24 +02:00
Masahiro Yamada
1084716f76 net: ipv6: unexport __init-annotated seg6_hmac_init()
[ Upstream commit 5801f064e35181c71857a80ff18af4dbec3c5f5c ]

EXPORT_SYMBOL and __init is a bad combination because the .init.text
section is freed up after the initialization. Hence, modules cannot
use symbols annotated __init. The access to a freed symbol may end up
with kernel panic.

modpost used to detect it, but it has been broken for a decade.

Recently, I fixed modpost so it started to warn it again, then this
showed up in linux-next builds.

There are two ways to fix it:

  - Remove __init
  - Remove EXPORT_SYMBOL

I chose the latter for this case because the caller (net/ipv6/seg6.c)
and the callee (net/ipv6/seg6_hmac.c) belong to the same module.
It seems an internal function call in ipv6.ko.

Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:36:18 +02:00
Eric Dumazet
3308676ec5 tcp: add accessors to read/set tp->snd_cwnd
[ Upstream commit 40570375356c874b1578e05c1dcc3ff7c1322dbe ]

We had various bugs over the years with code
breaking the assumption that tp->snd_cwnd is greater
than zero.

Lately, syzbot reported the WARN_ON_ONCE(!tp->prior_cwnd) added
in commit 8b8a321ff72c ("tcp: fix zero cwnd in tcp_cwnd_reduction")
can trigger, and without a repro we would have to spend
considerable time finding the bug.

Instead of complaining too late, we want to catch where
and when tp->snd_cwnd is set to an illegal value.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Link: https://lore.kernel.org/r/20220405233538.947344-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14 18:36:11 +02:00
jianghaoran
87402434ea ipv6: Don't send rs packets to the interface of ARPHRD_TUNNEL
[ Upstream commit b52e1cce31ca721e937d517411179f9196ee6135 ]

ARPHRD_TUNNEL interface can't process rs packets
and will generate TX errors

ex:
ip tunnel add ethn mode ipip local 192.168.1.1 remote 192.168.1.2
ifconfig ethn x.x.x.x

ethn: flags=209<UP,POINTOPOINT,RUNNING,NOARP>  mtu 1480
	inet x.x.x.x  netmask 255.255.255.255  destination x.x.x.x
	inet6 fe80::5efe:ac1e:3cdb  prefixlen 64  scopeid 0x20<link>
	tunnel   txqueuelen 1000  (IPIP Tunnel)
	RX packets 0  bytes 0 (0.0 B)
	RX errors 0  dropped 0  overruns 0  frame 0
	TX packets 0  bytes 0 (0.0 B)
	TX errors 3  dropped 0 overruns 0  carrier 0  collisions 0

Signed-off-by: jianghaoran <jianghaoran@kylinos.cn>
Link: https://lore.kernel.org/r/20220429053802.246681-1-jianghaoran@kylinos.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:22:35 +02:00
Niels Dossche
7665af570b ipv6: fix locking issues with loops over idev->addr_list
[ Upstream commit 51454ea42c1ab4e0c2828bb0d4d53957976980de ]

idev->addr_list needs to be protected by idev->lock. However, it is not
always possible to do so while iterating and performing actions on
inet6_ifaddr instances. For example, multiple functions (like
addrconf_{join,leave}_anycast) eventually call down to other functions
that acquire the idev->lock. The current code temporarily unlocked the
idev->lock during the loops, which can cause race conditions. Moving the
locks up is also not an appropriate solution as the ordering of lock
acquisition will be inconsistent with for example mc_lock.

This solution adds an additional field to inet6_ifaddr that is used
to temporarily add the instances to a temporary list while holding
idev->lock. The temporary list can then be traversed without holding
idev->lock. This change was done in two places. In addrconf_ifdown, the
list_for_each_entry_safe variant of the list loop is also no longer
necessary as there is no deletion within that specific loop.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20220403231523.45843-1-dossche.niels@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:22:31 +02:00
Willy Tarreau
1a8ee547da secure_seq: use the 64 bits of the siphash for port offset calculation
[ Upstream commit b2d057560b8107c633b39aabe517ff9d93f285e3 ]

SipHash replaced MD5 in secure_ipv{4,6}_port_ephemeral() via commit
7cd23e5300c1 ("secure_seq: use SipHash in place of MD5"), but the output
remained truncated to 32-bit only. In order to exploit more bits from the
hash, let's make the functions return the full 64-bit of siphash_3u32().
We also make sure the port offset calculation in __inet_hash_connect()
remains done on 32-bit to avoid the need for div_u64_rem() and an extra
cost on 32-bit systems.

Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Moshe Kol <moshe.kol@mail.huji.ac.il>
Cc: Yossi Gilad <yossi.gilad@mail.huji.ac.il>
Cc: Amit Klein <aksecurity@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 10:26:53 +02:00
Eric Dumazet
9bcb779ba8 mld: respect RCU rules in ip6_mc_source() and ip6_mc_msfilter()
commit a9384a4c1d250cb40cebf50e41459426d160b08e upstream.

Whenever RCU protected list replaces an object,
the pointer to the new object needs to be updated
_before_ the call to kfree_rcu() or call_rcu()

Also ip6_mc_msfilter() needs to update the pointer
before releasing the mc_lock mutex.

Note that linux-5.13 was supporting kfree_rcu(NULL, rcu),
so this fix does not need the conditional test I was
forced to use in the equivalent patch for IPv4.

Fixes: 882ba1f73c06 ("mld: convert ipv6_mc_socklist->sflist to RCU")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-12 12:30:18 +02:00
Martin Willi
891883c426 netfilter: Update ip6_route_me_harder to consider L3 domain
commit 8ddffdb9442a9d60b4a6e679ac48d7d21403a674 upstream.

The commit referenced below fixed packet re-routing if Netfilter mangles
a routing key property of a packet and the packet is routed in a VRF L3
domain. The fix, however, addressed IPv4 re-routing, only.

This commit applies the same behavior for IPv6. While at it, untangle
the nested ternary operator to make the code more readable.

Fixes: 6d8b49c3a3a3 ("netfilter: Update ip_route_me_harder to consider L3 domain")
Cc: stable@vger.kernel.org
Signed-off-by: Martin Willi <martin@strongswan.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-05-09 09:14:41 +02:00
Eric Dumazet
45b7fca32b tcp: make sure treq->af_specific is initialized
[ Upstream commit ba5a4fdd63ae0c575707030db0b634b160baddd7 ]

syzbot complained about a recent change in TCP stack,
hitting a NULL pointer [1]

tcp request sockets have an af_specific pointer, which
was used before the blamed change only for SYNACK generation
in non SYNCOOKIE mode.

tcp requests sockets momentarily created when third packet
coming from client in SYNCOOKIE mode were not using
treq->af_specific.

Make sure this field is populated, in the same way normal
TCP requests sockets do in tcp_conn_request().

[1]
TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies.  Check SNMP counters.
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 3695 Comm: syz-executor864 Not tainted 5.18.0-rc3-syzkaller-00224-g5fd1fe4807f9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tcp_create_openreq_child+0xe16/0x16b0 net/ipv4/tcp_minisocks.c:534
Code: 48 c1 ea 03 80 3c 02 00 0f 85 e5 07 00 00 4c 8b b3 28 01 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7e 08 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 c9 07 00 00 48 8b 3c 24 48 89 de 41 ff 56 08 48
RSP: 0018:ffffc90000de0588 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888076490330 RCX: 0000000000000100
RDX: 0000000000000001 RSI: ffffffff87d67ff0 RDI: 0000000000000008
RBP: ffff88806ee1c7f8 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87d67f00 R11: 0000000000000000 R12: ffff88806ee1bfc0
R13: ffff88801b0e0368 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f517fe58700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcead76960 CR3: 000000006f97b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 tcp_v6_syn_recv_sock+0x199/0x23b0 net/ipv6/tcp_ipv6.c:1267
 tcp_get_cookie_sock+0xc9/0x850 net/ipv4/syncookies.c:207
 cookie_v6_check+0x15c3/0x2340 net/ipv6/syncookies.c:258
 tcp_v6_cookie_check net/ipv6/tcp_ipv6.c:1131 [inline]
 tcp_v6_do_rcv+0x1148/0x13b0 net/ipv6/tcp_ipv6.c:1486
 tcp_v6_rcv+0x3305/0x3840 net/ipv6/tcp_ipv6.c:1725
 ip6_protocol_deliver_rcu+0x2e9/0x1900 net/ipv6/ip6_input.c:422
 ip6_input_finish+0x14c/0x2c0 net/ipv6/ip6_input.c:464
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:473
 dst_input include/net/dst.h:461 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0x27f/0x3b0 net/ipv6/ip6_input.c:297
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5405
 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5519
 process_backlog+0x3a0/0x7c0 net/core/dev.c:5847
 __napi_poll+0xb3/0x6e0 net/core/dev.c:6413
 napi_poll net/core/dev.c:6480 [inline]
 net_rx_action+0x8ec/0xc60 net/core/dev.c:6567
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097

Fixes: 5b0b9e4c2c89 ("tcp: md5: incorrect tcp_header_len for incoming connections")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-09 09:14:37 +02:00
Peilin Ye
6b59df7d4d ip_gre, ip6_gre: Fix race condition on o_seqno in collect_md mode
[ Upstream commit 31c417c948d7f6909cb63f0ac3298f3c38f8ce20 ]

As pointed out by Jakub Kicinski, currently using TUNNEL_SEQ in
collect_md mode is racy for [IP6]GRE[TAP] devices.  Consider the
following sequence of events:

1. An [IP6]GRE[TAP] device is created in collect_md mode using "ip link
   add ... external".  "ip" ignores "[o]seq" if "external" is specified,
   so TUNNEL_SEQ is off, and the device is marked as NETIF_F_LLTX (i.e.
   it uses lockless TX);
2. Someone sets TUNNEL_SEQ on outgoing skb's, using e.g.
   bpf_skb_set_tunnel_key() in an eBPF program attached to this device;
3. gre_fb_xmit() or __gre6_xmit() processes these skb's:

	gre_build_header(skb, tun_hlen,
			 flags, protocol,
			 tunnel_id_to_key32(tun_info->key.tun_id),
			 (flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
					      : 0);   ^^^^^^^^^^^^^^^^^

Since we are not using the TX lock (&txq->_xmit_lock), multiple CPUs may
try to do this tunnel->o_seqno++ in parallel, which is racy.  Fix it by
making o_seqno atomic_t.

As mentioned by Eric Dumazet in commit b790e01aee74 ("ip_gre: lockless
xmit"), making o_seqno atomic_t increases "chance for packets being out
of order at receiver" when NETIF_F_LLTX is on.

Maybe a better fix would be:

1. Do not ignore "oseq" in external mode.  Users MUST specify "oseq" if
   they want the kernel to allow sequencing of outgoing packets;
2. Reject all outgoing TUNNEL_SEQ packets if the device was not created
   with "oseq".

Unfortunately, that would break userspace.

We could now make [IP6]GRE[TAP] devices always NETIF_F_LLTX, but let us
do it in separate patches to keep this fix minimal.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Fixes: 77a5196a804e ("gre: add sequence number for collect md mode.")
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-09 09:14:36 +02:00
Peilin Ye
e5e985dd99 ip6_gre: Make o_seqno start from 0 in native mode
[ Upstream commit fde98ae91f79cab4e020f40c35ed23cbdc59661c ]

For IP6GRE and IP6GRETAP devices, currently o_seqno starts from 1 in
native mode.  According to RFC 2890 2.2., "The first datagram is sent
with a sequence number of 0."  Fix it.

It is worth mentioning that o_seqno already starts from 0 in collect_md
mode, see the "if (tunnel->parms.collect_md)" clause in __gre6_xmit(),
where tunnel->o_seqno is passed to gre_build_header() before getting
incremented.

Fixes: c12b395a4664 ("gre: Support GRE over IPv6")
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-09 09:14:36 +02:00
Eric Dumazet
652a540539 ipv6: make ip6_rt_gc_expire an atomic_t
[ Upstream commit 9cb7c013420f98fa6fd12fc6a5dc055170c108db ]

Reads and Writes to ip6_rt_gc_expire always have been racy,
as syzbot reported lately [1]

There is a possible risk of under-flow, leading
to unexpected high value passed to fib6_run_gc(),
although I have not observed this in the field.

Hosts hitting ip6_dst_gc() very hard are under pretty bad
state anyway.

[1]
BUG: KCSAN: data-race in ip6_dst_gc / ip6_dst_gc

read-write to 0xffff888102110744 of 4 bytes by task 13165 on cpu 1:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

read-write to 0xffff888102110744 of 4 bytes by task 11607 on cpu 0:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x00000bb3 -> 0x00000ba9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11607 Comm: kworker/0:21 Not tainted 5.18.0-rc1-syzkaller-00037-g42e7a03d3bad-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220413181333.649424-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-27 14:38:54 +02:00
Peilin Ye
d5049ef1f6 ip6_gre: Fix skb_under_panic in __gre6_xmit()
[ Upstream commit ab198e1d0dd8dc4bc7575fb50758e2cbd51e14e1 ]

Feng reported an skb_under_panic BUG triggered by running
test_ip6gretap() in tools/testing/selftests/bpf/test_tunnel.sh:

[   82.492551] skbuff: skb_under_panic: text:ffffffffb268bb8e len:403 put:12 head:ffff9997c5480000 data:ffff9997c547fff8 tail:0x18b end:0x2c0 dev:ip6gretap11
<...>
[   82.607380] Call Trace:
[   82.609389]  <TASK>
[   82.611136]  skb_push.cold.109+0x10/0x10
[   82.614289]  __gre6_xmit+0x41e/0x590
[   82.617169]  ip6gre_tunnel_xmit+0x344/0x3f0
[   82.620526]  dev_hard_start_xmit+0xf1/0x330
[   82.623882]  sch_direct_xmit+0xe4/0x250
[   82.626961]  __dev_queue_xmit+0x720/0xfe0
<...>
[   82.633431]  packet_sendmsg+0x96a/0x1cb0
[   82.636568]  sock_sendmsg+0x30/0x40
<...>

The following sequence of events caused the BUG:

1. During ip6gretap device initialization, tunnel->tun_hlen (e.g. 4) is
   calculated based on old flags (see ip6gre_calc_hlen());
2. packet_snd() reserves header room for skb A, assuming
   tunnel->tun_hlen is 4;
3. Later (in clsact Qdisc), the eBPF program sets a new tunnel key for
   skb A using bpf_skb_set_tunnel_key() (see _ip6gretap_set_tunnel());
4. __gre6_xmit() detects the new tunnel key, and recalculates
   "tun_hlen" (e.g. 12) based on new flags (e.g. TUNNEL_KEY and
   TUNNEL_SEQ);
5. gre_build_header() calls skb_push() with insufficient reserved header
   room, triggering the BUG.

As sugguested by Cong, fix it by moving the call to skb_cow_head() after
the recalculation of tun_hlen.

Reproducer:

  OBJ=$LINUX/tools/testing/selftests/bpf/test_tunnel_kern.o

  ip netns add at_ns0
  ip link add veth0 type veth peer name veth1
  ip link set veth0 netns at_ns0
  ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
  ip netns exec at_ns0 ip link set dev veth0 up
  ip link set dev veth1 up mtu 1500
  ip addr add dev veth1 172.16.1.200/24

  ip netns exec at_ns0 ip addr add ::11/96 dev veth0
  ip netns exec at_ns0 ip link set dev veth0 up
  ip addr add dev veth1 ::22/96
  ip link set dev veth1 up

  ip netns exec at_ns0 \
  	ip link add dev ip6gretap00 type ip6gretap seq flowlabel 0xbcdef key 2 \
  	local ::11 remote ::22

  ip netns exec at_ns0 ip addr add dev ip6gretap00 10.1.1.100/24
  ip netns exec at_ns0 ip addr add dev ip6gretap00 fc80::100/96
  ip netns exec at_ns0 ip link set dev ip6gretap00 up

  ip link add dev ip6gretap11 type ip6gretap external
  ip addr add dev ip6gretap11 10.1.1.200/24
  ip addr add dev ip6gretap11 fc80::200/24
  ip link set dev ip6gretap11 up

  tc qdisc add dev ip6gretap11 clsact
  tc filter add dev ip6gretap11 egress bpf da obj $OBJ sec ip6gretap_set_tunnel
  tc filter add dev ip6gretap11 ingress bpf da obj $OBJ sec ip6gretap_get_tunnel

  ping6 -c 3 -w 10 -q ::11

Fixes: 6712abc168eb ("ip6_gre: add ip6 gre and gretap collect_md mode")
Reported-by: Feng Zhou <zhoufeng.zf@bytedance.com>
Co-developed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-27 14:38:53 +02:00
Peilin Ye
3cc2f6b71e ip6_gre: Avoid updating tunnel->tun_hlen in __gre6_xmit()
[ Upstream commit f40c064e933d7787ca7411b699504d7a2664c1f5 ]

Do not update tunnel->tun_hlen in data plane code.  Use a local variable
instead, just like "tunnel_hlen" in net/ipv4/ip_gre.c:gre_fb_xmit().

Co-developed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-27 14:38:53 +02:00
Sabrina Dubroca
a583f2f3c8 esp: limit skb_page_frag_refill use to a single page
[ Upstream commit 5bd8baab087dff657e05387aee802e70304cc813 ]

Commit ebe48d368e97 ("esp: Fix possible buffer overflow in ESP
transformation") tried to fix skb_page_frag_refill usage in ESP by
capping allocsize to 32k, but that doesn't completely solve the issue,
as skb_page_frag_refill may return a single page. If that happens, we
will write out of bounds, despite the check introduced in the previous
patch.

This patch forces COW in cases where we would end up calling
skb_page_frag_refill with a size larger than a page (first in
esp_output_head with tailen, then in esp_output_tail with
skb->data_len).

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-27 14:38:52 +02:00
Nicolas Dichtel
adee01bbf6 ipv6: fix panic when forwarding a pkt with no in6 dev
commit e3fa461d8b0e185b7da8a101fe94dfe6dd500ac0 upstream.

kongweibin reported a kernel panic in ip6_forward() when input interface
has no in6 dev associated.

The following tc commands were used to reproduce this panic:
tc qdisc del dev vxlan100 root
tc qdisc add dev vxlan100 root netem corrupt 5%

CC: stable@vger.kernel.org
Fixes: ccd27f05ae7b ("ipv6: fix 'disable_policy' for fwd packets")
Reported-by: kongweibin <kongweibin2@huawei.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-20 09:34:19 +02:00
David Ahern
070aa68f8f ipv6: Fix stats accounting in ip6_pkt_drop
[ Upstream commit 1158f79f82d437093aeed87d57df0548bdd68146 ]

VRF devices are the loopbacks for VRFs, and a loopback can not be
assigned to a VRF. Accordingly, the condition in ip6_pkt_drop should
be '||' not '&&'.

Fixes: 1d3fd8a10bed ("vrf: Use orig netdev to count Ip6InNoRoutes and a fresh route lookup when sending dest unreach")
Reported-by: Pudak, Filip <Filip.Pudak@windriver.com>
Reported-by: Xiao, Jiguang <Jiguang.Xiao@windriver.com>
Signed-off-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220404150908.2937-1-dsahern@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 20:59:18 +02:00
Sebastian Andrzej Siewior
aa9c9fd0ef tcp: Don't acquire inet_listen_hashbucket::lock with disabled BH.
[ Upstream commit 4f9bf2a2f5aacf988e6d5e56b961ba45c5a25248 ]

Commit
   9652dc2eb9e40 ("tcp: relax listening_hash operations")

removed the need to disable bottom half while acquiring
listening_hash.lock. There are still two callers left which disable
bottom half before the lock is acquired.

On PREEMPT_RT the softirqs are preemptible and local_bh_disable() acts
as a lock to ensure that resources, that are protected by disabling
bottom halves, remain protected.
This leads to a circular locking dependency if the lock acquired with
disabled bottom halves is also acquired with enabled bottom halves
followed by disabling bottom halves. This is the reverse locking order.
It has been observed with inet_listen_hashbucket:🔒

local_bh_disable() + spin_lock(&ilb->lock):
  inet_listen()
    inet_csk_listen_start()
      sk->sk_prot->hash() := inet_hash()
	local_bh_disable()
	__inet_hash()
	  spin_lock(&ilb->lock);
	    acquire(&ilb->lock);

Reverse order: spin_lock(&ilb2->lock) + local_bh_disable():
  tcp_seq_next()
    listening_get_next()
      spin_lock(&ilb2->lock);
	acquire(&ilb2->lock);

  tcp4_seq_show()
    get_tcp4_sock()
      sock_i_ino()
	read_lock_bh(&sk->sk_callback_lock);
	  acquire(softirq_ctrl)	// <---- whoops
	  acquire(&sk->sk_callback_lock)

Drop local_bh_disable() around __inet_hash() which acquires
listening_hash->lock. Split inet_unhash() and acquire the
listen_hashbucket lock without disabling bottom halves; the inet_ehash
lock with disabled bottom halves.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lkml.kernel.org/r/12d6f9879a97cd56c09fb53dee343cbb14f7f1f7.camel@gmx.de
Link: https://lkml.kernel.org/r/X9CheYjuXWc75Spa@hirez.programming.kicks-ass.net
Link: https://lore.kernel.org/r/YgQOebeZ10eNx1W6@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 20:59:04 +02:00
Eric Dumazet
4790998fdd ipv6: make mc_forwarding atomic
[ Upstream commit 145c7a793838add5e004e7d49a67654dc7eba147 ]

This fixes minor data-races in ip6_mc_input() and
batadv_mcast_mla_rtr_flags_softif_get_ipv6()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-13 20:59:03 +02:00
Lina Wang
189bdde30b xfrm: fix tunnel model fragmentation behavior
[ Upstream commit 4ff2980b6bd2aa6b4ded3ce3b7c0ccfab29980af ]

in tunnel mode, if outer interface(ipv4) is less, it is easily to let
inner IPV6 mtu be less than 1280. If so, a Packet Too Big ICMPV6 message
is received. When send again, packets are fragmentized with 1280, they
are still rejected with ICMPV6(Packet Too Big) by xfrmi_xmit2().

According to RFC4213 Section3.2.2:
if (IPv4 path MTU - 20) is less than 1280
	if packet is larger than 1280 bytes
		Send ICMPv6 "packet too big" with MTU=1280
                Drop packet
        else
		Encapsulate but do not set the Don't Fragment
                flag in the IPv4 header.  The resulting IPv4
                packet might be fragmented by the IPv4 layer
                on the encapsulator or by some router along
                the IPv4 path.
	endif
else
	if packet is larger than (IPv4 path MTU - 20)
        	Send ICMPv6 "packet too big" with
                MTU = (IPv4 path MTU - 20).
                Drop packet.
        else
                Encapsulate and set the Don't Fragment flag
                in the IPv4 header.
        endif
endif
Packets should be fragmentized with ipv4 outer interface, so change it.

After it is fragemtized with ipv4, there will be double fragmenation.
No.48 & No.51 are ipv6 fragment packets, No.48 is double fragmentized,
then tunneled with IPv4(No.49& No.50), which obey spec. And received peer
cannot decrypt it rightly.

48              2002::10        2002::11 1296(length) IPv6 fragment (off=0 more=y ident=0xa20da5bc nxt=50)
49   0x0000 (0) 2002::10        2002::11 1304         IPv6 fragment (off=0 more=y ident=0x7448042c nxt=44)
50   0x0000 (0) 2002::10        2002::11 200          ESP (SPI=0x00035000)
51              2002::10        2002::11 180          Echo (ping) request
52   0x56dc     2002::10        2002::11 248          IPv6 fragment (off=1232 more=n ident=0xa20da5bc nxt=50)

xfrm6_noneed_fragment has fixed above issues. Finally, it acted like below:
1   0x6206 192.168.1.138   192.168.1.1 1316 Fragmented IP protocol (proto=Encap Security Payload 50, off=0, ID=6206) [Reassembled in #2]
2   0x6206 2002::10        2002::11    88   IPv6 fragment (off=0 more=y ident=0x1f440778 nxt=50)
3   0x0000 2002::10        2002::11    248  ICMPv6    Echo (ping) request

Signed-off-by: Lina Wang <lina.wang@mediatek.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:22:46 +02:00
Tadeusz Struk
2317fd3b12 net: ipv6: fix skb_over_panic in __ip6_append_data
commit 5e34af4142ffe68f01c8a9acae83300f8911e20c upstream.

Syzbot found a kernel bug in the ipv6 stack:
LINK: https://syzkaller.appspot.com/bug?id=205d6f11d72329ab8d62a610c44c5e7e25415580
The reproducer triggers it by sending a crafted message via sendmmsg()
call, which triggers skb_over_panic, and crashes the kernel:

skbuff: skb_over_panic: text:ffffffff84647fb4 len:65575 put:65575
head:ffff888109ff0000 data:ffff888109ff0088 tail:0x100af end:0xfec0
dev:<NULL>

Update the check that prevents an invalid packet with MTU equal
to the fregment header size to eat up all the space for payload.

The reproducer can be found here:
LINK: https://syzkaller.appspot.com/text?tag=ReproC&x=1648c83fb00000

Reported-by: syzbot+e223cf47ec8ae183f2a0@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20220310232538.1044947-1-tadeusz.struk@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-28 09:58:42 +02:00
Sabrina Dubroca
b9820bf09f esp6: fix check on ipv6_skip_exthdr's return value
[ Upstream commit 4db4075f92af2b28f415fc979ab626e6b37d67b6 ]

Commit 5f9c55c8066b ("ipv6: check return value of ipv6_skip_exthdr")
introduced an incorrect check, which leads to all ESP packets over
either TCPv6 or UDPv6 encapsulation being dropped. In this particular
case, offset is negative, since skb->data points to the ESP header in
the following chain of headers, while skb->network_header points to
the IPv6 header:

    IPv6 | ext | ... | ext | UDP | ESP | ...

That doesn't seem to be a problem, especially considering that if we
reach esp6_input_done2, we're guaranteed to have a full set of headers
available (otherwise the packet would have been dropped earlier in the
stack). However, it means that the return value will (intentionally)
be negative. We can make the test more specific, as the expected
return value of ipv6_skip_exthdr will be the (negated) size of either
a UDP header, or a TCP header with possible options.

In the future, we should probably either make ipv6_skip_exthdr
explicitly accept negative offsets (and adjust its return value for
error cases), or make ipv6_skip_exthdr only take non-negative
offsets (and audit all callers).

Fixes: 5f9c55c8066b ("ipv6: check return value of ipv6_skip_exthdr")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-23 09:16:41 +01:00
Niels Dossche
041616a22c ipv6: prevent a possible race condition with lifetimes
[ Upstream commit 6c0d8833a605e195ae219b5042577ce52bf71fff ]

valid_lft, prefered_lft and tstamp are always accessed under the lock
"lock" in other places. Reading these without taking the lock may result
in inconsistencies regarding the calculation of the valid and preferred
variables since decisions are taken on these fields for those variables.

Signed-off-by: Niels Dossche <dossche.niels@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Niels Dossche <niels.dossche@ugent.be>
Link: https://lore.kernel.org/r/20220223131954.6570-1-niels.dossche@ugent.be
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-16 14:23:41 +01:00
Steffen Klassert
e5d078d21f esp: Fix BEET mode inter address family tunneling on GSO
[ Upstream commit 053c8fdf2c930efdff5496960842bbb5c34ad43a ]

The xfrm{4,6}_beet_gso_segment() functions did not correctly set the
SKB_GSO_IPXIP4 and SKB_GSO_IPXIP6 gso types for the address family
tunneling case. Fix this by setting these gso types.

Fixes: 384a46ea7bdc7 ("esp4: add gso_segment for esp4 beet mode")
Fixes: 7f9e40eb18a99 ("esp6: add gso_segment for esp6 beet mode")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-16 14:23:36 +01:00
Steffen Klassert
4aaabbffc3 esp: Fix possible buffer overflow in ESP transformation
[ Upstream commit ebe48d368e97d007bfeb76fcb065d6cfc4c96645 ]

The maximum message size that can be send is bigger than
the  maximum site that skb_page_frag_refill can allocate.
So it is possible to write beyond the allocated buffer.

Fix this by doing a fallback to COW in that case.

v2:

Avoid get get_order() costs as suggested by Linus Torvalds.

Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible")
Reported-by: valis <sec@valis.email>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-16 14:23:36 +01:00
Jiri Bohac
8b89349689 Revert "xfrm: xfrm_state_mtu should return at least 1280 for ipv6"
commit a6d95c5a628a09be129f25d5663a7e9db8261f51 upstream.

This reverts commit b515d2637276a3810d6595e10ab02c13bfd0b63a.

Commit b515d2637276a3810d6595e10ab02c13bfd0b63a ("xfrm: xfrm_state_mtu
should return at least 1280 for ipv6") in v5.14 breaks the TCP MSS
calculation in ipsec transport mode, resulting complete stalls of TCP
connections. This happens when the (P)MTU is 1280 or slighly larger.

The desired formula for the MSS is:
MSS = (MTU - ESP_overhead) - IP header - TCP header

However, the above commit clamps the (MTU - ESP_overhead) to a
minimum of 1280, turning the formula into
MSS = max(MTU - ESP overhead, 1280) -  IP header - TCP header

With the (P)MTU near 1280, the calculated MSS is too large and the
resulting TCP packets never make it to the destination because they
are over the actual PMTU.

The above commit also causes suboptimal double fragmentation in
xfrm tunnel mode, as described in
https://lore.kernel.org/netdev/20210429202529.codhwpc7w6kbudug@dwarf.suse.cz/

The original problem the above commit was trying to fix is now fixed
by commit 6596a0229541270fb8d38d989f91b78838e5e9da ("xfrm: fix MTU
regression").

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:12:54 +01:00
j.nixdorf@avm.de
b117815152 net: ipv6: ensure we call ipv6_mc_down() at most once
commit 9995b408f17ff8c7f11bc725c8aa225ba3a63b1c upstream.

There are two reasons for addrconf_notify() to be called with NETDEV_DOWN:
either the network device is actually going down, or IPv6 was disabled
on the interface.

If either of them stays down while the other is toggled, we repeatedly
call the code for NETDEV_DOWN, including ipv6_mc_down(), while never
calling the corresponding ipv6_mc_up() in between. This will cause a
new entry in idev->mc_tomb to be allocated for each multicast group
the interface is subscribed to, which in turn leaks one struct ifmcaddr6
per nontrivial multicast group the interface is subscribed to.

The following reproducer will leak at least $n objects:

ip addr add ff2e::4242/32 dev eth0 autojoin
sysctl -w net.ipv6.conf.eth0.disable_ipv6=1
for i in $(seq 1 $n); do
	ip link set up eth0; ip link set down eth0
done

Joining groups with IPV6_ADD_MEMBERSHIP (unprivileged) or setting the
sysctl net.ipv6.conf.eth0.forwarding to 1 (=> subscribing to ff02::2)
can also be used to create a nontrivial idev->mc_list, which will the
leak objects with the right up-down-sequence.

Based on both sources for NETDEV_DOWN events the interface IPv6 state
should be considered:

 - not ready if the network interface is not ready OR IPv6 is disabled
   for it
 - ready if the network interface is ready AND IPv6 is enabled for it

The functions ipv6_mc_up() and ipv6_down() should only be run when this
state changes.

Implement this by remembering when the IPv6 state is ready, and only
run ipv6_mc_down() if it actually changed from ready to not ready.

The other direction (not ready -> ready) already works correctly, as:

 - the interface notification triggered codepath for NETDEV_UP /
   NETDEV_CHANGE returns early if ipv6 is disabled, and
 - the disable_ipv6=0 triggered codepath skips fully initializing the
   interface as long as addrconf_link_ready(dev) returns false
 - calling ipv6_mc_up() repeatedly does not leak anything

Fixes: 3ce62a84d53c ("ipv6: exit early in addrconf_notify() if IPv6 is disabled")
Signed-off-by: Johannes Nixdorf <j.nixdorf@avm.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:12:45 +01:00
Jiri Bohac
75cbedd333 xfrm: fix MTU regression
commit 6596a0229541270fb8d38d989f91b78838e5e9da upstream.

Commit 749439bfac6e1a2932c582e2699f91d329658196 ("ipv6: fix udpv6
sendmsg crash caused by too small MTU") breaks PMTU for xfrm.

A Packet Too Big ICMPv6 message received in response to an ESP
packet will prevent all further communication through the tunnel
if the reported MTU minus the ESP overhead is smaller than 1280.

E.g. in a case of a tunnel-mode ESP with sha256/aes the overhead
is 92 bytes. Receiving a PTB with MTU of 1371 or less will result
in all further packets in the tunnel dropped. A ping through the
tunnel fails with "ping: sendmsg: Invalid argument".

Apparently the MTU on the xfrm route is smaller than 1280 and
fails the check inside ip6_setup_cork() added by 749439bf.

We found this by debugging USGv6/ipv6ready failures. Failing
tests are: "Phase-2 Interoperability Test Scenario IPsec" /
5.3.11 and 5.4.11 (Tunnel Mode: Fragmentation).

Commit b515d2637276a3810d6595e10ab02c13bfd0b63a ("xfrm:
xfrm_state_mtu should return at least 1280 for ipv6") attempted
to fix this but caused another regression in TCP MSS calculations
and had to be reverted.

The patch below fixes the situation by dropping the MTU
check and instead checking for the underflows described in the
749439bf commit message.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Fixes: 749439bfac6e ("ipv6: fix udpv6 sendmsg crash caused by too small MTU")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:12:44 +01:00
Eric Dumazet
771aca9bc7 ipv6: fix skb drops in igmp6_event_query() and igmp6_event_report()
[ Upstream commit 2d3916f3189172d5c69d33065c3c21119fe539fc ]

While investigating on why a synchronize_net() has been added recently
in ipv6_mc_down(), I found that igmp6_event_query() and igmp6_event_report()
might drop skbs in some cases.

Discussion about removing synchronize_net() from ipv6_mc_down()
will happen in a different thread.

Fixes: f185de28d9ae ("mld: add new workqueues for process mld events")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220303173728.937869-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-08 19:12:33 +01:00
Eric Dumazet
ff999198ec net-timestamp: convert sk->sk_tskey to atomic_t
[ Upstream commit a1cdec57e03a1352e92fbbe7974039dda4efcec0 ]

UDP sendmsg() can be lockless, this is causing all kinds
of data races.

This patch converts sk->sk_tskey to remove one of these races.

BUG: KCSAN: data-race in __ip_append_data / __ip_append_data

read to 0xffff8881035d4b6c of 4 bytes by task 8877 on cpu 1:
 __ip_append_data+0x1c1/0x1de0 net/ipv4/ip_output.c:994
 ip_make_skb+0x13f/0x2d0 net/ipv4/ip_output.c:1636
 udp_sendmsg+0x12bd/0x14c0 net/ipv4/udp.c:1249
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0x39a/0x510 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff8881035d4b6c of 4 bytes by task 8880 on cpu 0:
 __ip_append_data+0x1d8/0x1de0 net/ipv4/ip_output.c:994
 ip_make_skb+0x13f/0x2d0 net/ipv4/ip_output.c:1636
 udp_sendmsg+0x12bd/0x14c0 net/ipv4/udp.c:1249
 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0x39a/0x510 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000054d -> 0x0000054e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8880 Comm: syz-executor.5 Not tainted 5.17.0-rc2-syzkaller-00167-gdcb85f85fa6f-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 09c2d251b707 ("net-timestamp: add key to disambiguate concurrent datagrams")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-02 11:48:01 +01:00
Tao Liu
899e56a1ad gso: do not skip outer ip header in case of ipip and net_failover
commit cc20cced0598d9a5ff91ae4ab147b3b5e99ee819 upstream.

We encounter a tcp drop issue in our cloud environment. Packet GROed in
host forwards to a VM virtio_net nic with net_failover enabled. VM acts
as a IPVS LB with ipip encapsulation. The full path like:
host gro -> vm virtio_net rx -> net_failover rx -> ipvs fullnat
 -> ipip encap -> net_failover tx -> virtio_net tx

When net_failover transmits a ipip pkt (gso_type = 0x0103, which means
SKB_GSO_TCPV4, SKB_GSO_DODGY and SKB_GSO_IPXIP4), there is no gso
did because it supports TSO and GSO_IPXIP4. But network_header points to
inner ip header.

Call Trace:
 tcp4_gso_segment        ------> return NULL
 inet_gso_segment        ------> inner iph, network_header points to
 ipip_gso_segment
 inet_gso_segment        ------> outer iph
 skb_mac_gso_segment

Afterwards virtio_net transmits the pkt, only inner ip header is modified.
And the outer one just keeps unchanged. The pkt will be dropped in remote
host.

Call Trace:
 inet_gso_segment        ------> inner iph, outer iph is skipped
 skb_mac_gso_segment
 __skb_gso_segment
 validate_xmit_skb
 validate_xmit_skb_list
 sch_direct_xmit
 __qdisc_run
 __dev_queue_xmit        ------> virtio_net
 dev_hard_start_xmit
 __dev_queue_xmit        ------> net_failover
 ip_finish_output2
 ip_output
 iptunnel_xmit
 ip_tunnel_xmit
 ipip_tunnel_xmit        ------> ipip
 dev_hard_start_xmit
 __dev_queue_xmit
 ip_finish_output2
 ip_output
 ip_forward
 ip_rcv
 __netif_receive_skb_one_core
 netif_receive_skb_internal
 napi_gro_receive
 receive_buf
 virtnet_poll
 net_rx_action

The root cause of this issue is specific with the rare combination of
SKB_GSO_DODGY and a tunnel device that adds an SKB_GSO_ tunnel option.
SKB_GSO_DODGY is set from external virtio_net. We need to reset network
header when callbacks.gso_segment() returns NULL.

This patch also includes ipv6_gso_segment(), considering SIT, etc.

Fixes: cb32f511a70b ("ipip: add GSO/TSO support")
Signed-off-by: Tao Liu <thomas.liu@ucloud.cn>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-02 11:47:56 +01:00
Willem de Bruijn
d51cd648db ipv6: per-netns exclusive flowlabel checks
commit 0b0dff5b3b98c5c7ce848151df9da0b3cdf0cc8b upstream.

Ipv6 flowlabels historically require a reservation before use.
Optionally in exclusive mode (e.g., user-private).

Commit 59c820b2317f ("ipv6: elide flowlabel check if no exclusive
leases exist") introduced a fastpath that avoids this check when no
exclusive leases exist in the system, and thus any flowlabel use
will be granted.

That allows skipping the control operation to reserve a flowlabel
entirely. Though with a warning if the fast path fails:

  This is an optimization. Robust applications still have to revert to
  requesting leases if the fast path fails due to an exclusive lease.

Still, this is subtle. Better isolate network namespaces from each
other. Flowlabels are per-netns. Also record per-netns whether
exclusive leases are in use. Then behavior does not change based on
activity in other netns.

Changes
  v2
    - wrap in IS_ENABLED(CONFIG_IPV6) to avoid breakage if disabled

Fixes: 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist")
Link: https://lore.kernel.org/netdev/MWHPR2201MB1072BCCCFCE779E4094837ACD0329@MWHPR2201MB1072.namprd22.prod.outlook.com/
Reported-by: Congyu Liu <liu3101@purdue.edu>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Tested-by: Congyu Liu <liu3101@purdue.edu>
Link: https://lore.kernel.org/r/20220215160037.1976072-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-23 12:03:10 +01:00
Ignat Korchagin
3e11ef1903 ipv6: mcast: use rcu-safe version of ipv6_get_lladdr()
commit 26394fc118d6115390bd5b3a0fb17096271da227 upstream.

Some time ago 8965779d2c0e ("ipv6,mcast: always hold idev->lock before mca_lock")
switched ipv6_get_lladdr() to __ipv6_get_lladdr(), which is rcu-unsafe
version. That was OK, because idev->lock was held for these codepaths.

In 88e2ca308094 ("mld: convert ifmcaddr6 to RCU") these external locks were
removed, so we probably need to restore the original rcu-safe call.

Otherwise, we occasionally get a machine crashed/stalled with the following
in dmesg:

[ 3405.966610][T230589] general protection fault, probably for non-canonical address 0xdead00000000008c: 0000 [#1] SMP NOPTI
[ 3405.982083][T230589] CPU: 44 PID: 230589 Comm: kworker/44:3 Tainted: G           O      5.15.19-cloudflare-2022.2.1 #1
[ 3405.998061][T230589] Hardware name: SUPA-COOL-SERV
[ 3406.009552][T230589] Workqueue: mld mld_ifc_work
[ 3406.017224][T230589] RIP: 0010:__ipv6_get_lladdr+0x34/0x60
[ 3406.025780][T230589] Code: 57 10 48 83 c7 08 48 89 e5 48 39 d7 74 3e 48 8d 82 38 ff ff ff eb 13 48 8b 90 d0 00 00 00 48 8d 82 38 ff ff ff 48 39 d7 74 22 <66> 83 78 32 20 77 1b 75 e4 89 ca 23 50 2c 75 dd 48 8b 50 08 48 8b
[ 3406.055748][T230589] RSP: 0018:ffff94e4b3fc3d10 EFLAGS: 00010202
[ 3406.065617][T230589] RAX: dead00000000005a RBX: ffff94e4b3fc3d30 RCX: 0000000000000040
[ 3406.077477][T230589] RDX: dead000000000122 RSI: ffff94e4b3fc3d30 RDI: ffff8c3a31431008
[ 3406.089389][T230589] RBP: ffff94e4b3fc3d10 R08: 0000000000000000 R09: 0000000000000000
[ 3406.101445][T230589] R10: ffff8c3a31430000 R11: 000000000000000b R12: ffff8c2c37887100
[ 3406.113553][T230589] R13: ffff8c3a39537000 R14: 00000000000005dc R15: ffff8c3a31431000
[ 3406.125730][T230589] FS:  0000000000000000(0000) GS:ffff8c3b9fc80000(0000) knlGS:0000000000000000
[ 3406.138992][T230589] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3406.149895][T230589] CR2: 00007f0dfea1db60 CR3: 000000387b5f2000 CR4: 0000000000350ee0
[ 3406.162421][T230589] Call Trace:
[ 3406.170235][T230589]  <TASK>
[ 3406.177736][T230589]  mld_newpack+0xfe/0x1a0
[ 3406.186686][T230589]  add_grhead+0x87/0xa0
[ 3406.195498][T230589]  add_grec+0x485/0x4e0
[ 3406.204310][T230589]  ? newidle_balance+0x126/0x3f0
[ 3406.214024][T230589]  mld_ifc_work+0x15d/0x450
[ 3406.223279][T230589]  process_one_work+0x1e6/0x380
[ 3406.232982][T230589]  worker_thread+0x50/0x3a0
[ 3406.242371][T230589]  ? rescuer_thread+0x360/0x360
[ 3406.252175][T230589]  kthread+0x127/0x150
[ 3406.261197][T230589]  ? set_kthread_struct+0x40/0x40
[ 3406.271287][T230589]  ret_from_fork+0x22/0x30
[ 3406.280812][T230589]  </TASK>
[ 3406.288937][T230589] Modules linked in: ... [last unloaded: kheaders]
[ 3406.476714][T230589] ---[ end trace 3525a7655f2f3b9e ]---

Fixes: 88e2ca308094 ("mld: convert ifmcaddr6 to RCU")
Reported-by: David Pinilla Caparros <dpini@cloudflare.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-23 12:03:10 +01:00
Eric Dumazet
9ed25183e6 ipv6: fix data-race in fib6_info_hw_flags_set / fib6_purge_rt
commit d95d6320ba7a51d61c097ffc3bcafcf70283414e upstream.

Because fib6_info_hw_flags_set() is called without any synchronization,
all accesses to gi6->offload, fi->trap and fi->offload_failed
need some basic protection like READ_ONCE()/WRITE_ONCE().

BUG: KCSAN: data-race in fib6_info_hw_flags_set / fib6_purge_rt

read to 0xffff8881087d5886 of 1 bytes by task 13953 on cpu 0:
 fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1007 [inline]
 fib6_purge_rt+0x4f/0x580 net/ipv6/ip6_fib.c:1033
 fib6_del_route net/ipv6/ip6_fib.c:1983 [inline]
 fib6_del+0x696/0x890 net/ipv6/ip6_fib.c:2028
 __ip6_del_rt net/ipv6/route.c:3876 [inline]
 ip6_del_rt+0x83/0x140 net/ipv6/route.c:3891
 __ipv6_dev_ac_dec+0x2b5/0x370 net/ipv6/anycast.c:374
 ipv6_dev_ac_dec net/ipv6/anycast.c:387 [inline]
 __ipv6_sock_ac_close+0x141/0x200 net/ipv6/anycast.c:207
 ipv6_sock_ac_close+0x79/0x90 net/ipv6/anycast.c:220
 inet6_release+0x32/0x50 net/ipv6/af_inet6.c:476
 __sock_release net/socket.c:650 [inline]
 sock_close+0x6c/0x150 net/socket.c:1318
 __fput+0x295/0x520 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x160/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff8881087d5886 of 1 bytes by task 1912 on cpu 1:
 fib6_info_hw_flags_set+0x155/0x3b0 net/ipv6/route.c:6230
 nsim_fib6_rt_hw_flags_set drivers/net/netdevsim/fib.c:668 [inline]
 nsim_fib6_rt_add drivers/net/netdevsim/fib.c:691 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:756 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:853 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:886 [inline]
 nsim_fib_event_work+0x284f/0x2cf0 drivers/net/netdevsim/fib.c:1477
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x2c7/0x2e0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

value changed: 0x22 -> 0x2a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1912 Comm: kworker/1:3 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events nsim_fib_event_work

Fixes: 0c5fcf9e249e ("IPv6: Add "offload failed" indication to routes")
Fixes: bb3c4ab93e44 ("ipv6: Add "offload" and "trap" indications to routes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Amit Cohen <amcohen@nvidia.com>
Cc: Ido Schimmel <idosch@nvidia.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220216173217.3792411-2-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-23 12:03:10 +01:00
Eric Dumazet
3cab045c99 ipmr,ip6mr: acquire RTNL before calling ip[6]mr_free_table() on failure path
[ Upstream commit 5611a00697c8ecc5aad04392bea629e9d6a20463 ]

ip[6]mr_free_table() can only be called under RTNL lock.

RTNL: assertion failed at net/core/dev.c (10367)
WARNING: CPU: 1 PID: 5890 at net/core/dev.c:10367 unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367
Modules linked in:
CPU: 1 PID: 5890 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller-11627-g422ee58dc0ef #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367
Code: 0f 85 9b ee ff ff e8 69 07 4b fa ba 7f 28 00 00 48 c7 c6 00 90 ae 8a 48 c7 c7 40 90 ae 8a c6 05 6d b1 51 06 01 e8 8c 90 d8 01 <0f> 0b e9 70 ee ff ff e8 3e 07 4b fa 4c 89 e7 e8 86 2a 59 fa e9 ee
RSP: 0018:ffffc900046ff6e0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888050f51d00 RSI: ffffffff815fa008 RDI: fffff520008dfece
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815f3d6e R11: 0000000000000000 R12: 00000000fffffff4
R13: dffffc0000000000 R14: ffffc900046ff750 R15: ffff88807b7dc000
FS:  00007f4ab736e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fee0b4f8990 CR3: 000000001e7d2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mroute_clean_tables+0x244/0xb40 net/ipv6/ip6mr.c:1509
 ip6mr_free_table net/ipv6/ip6mr.c:389 [inline]
 ip6mr_rules_init net/ipv6/ip6mr.c:246 [inline]
 ip6mr_net_init net/ipv6/ip6mr.c:1306 [inline]
 ip6mr_net_init+0x3f0/0x4e0 net/ipv6/ip6mr.c:1298
 ops_init+0xaf/0x470 net/core/net_namespace.c:140
 setup_net+0x54f/0xbb0 net/core/net_namespace.c:331
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:475
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178
 copy_process+0x2e0c/0x7300 kernel/fork.c:2167
 kernel_clone+0xe7/0xab0 kernel/fork.c:2555
 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4ab89f9059
Code: Unable to access opcode bytes at RIP 0x7f4ab89f902f.
RSP: 002b:00007f4ab736e118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f4ab8b0bf60 RCX: 00007f4ab89f9059
RDX: 0000000020000280 RSI: 0000000020000270 RDI: 0000000040200000
RBP: 00007f4ab8a5308d R08: 0000000020000300 R09: 0000000020000300
R10: 00000000200002c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc3977cc1f R14: 00007f4ab736e300 R15: 0000000000022000
 </TASK>

Fixes: f243e5a7859a ("ipmr,ip6mr: call ip6mr_free_table() on failure path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <cong.wang@bytedance.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220208053451.2885398-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-16 12:56:29 +01:00
Guillaume Nault
e406345f8a Revert "ipv6: Honor all IPv6 PIO Valid Lifetime values"
[ Upstream commit 36268983e90316b37000a005642af42234dabb36 ]

This reverts commit b75326c201242de9495ff98e5d5cff41d7fc0d9d.

This commit breaks Linux compatibility with USGv6 tests. The RFC this
commit was based on is actually an expired draft: no published RFC
currently allows the new behaviour it introduced.

Without full IETF endorsement, the flash renumbering scenario this
patch was supposed to enable is never going to work, as other IPv6
equipements on the same LAN will keep the 2 hours limit.

Fixes: b75326c20124 ("ipv6: Honor all IPv6 PIO Valid Lifetime values")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-01 17:27:14 +01:00
Eric Dumazet
fe36a67e82 ipv6: annotate accesses to fn->fn_sernum
commit aafc2e3285c2d7a79b7ee15221c19fbeca7b1509 upstream.

struct fib6_node's fn_sernum field can be
read while other threads change it.

Add READ_ONCE()/WRITE_ONCE() annotations.

Do not change existing smp barriers in fib6_get_cookie_safe()
and __fib6_update_sernum_upto_root()

syzbot reported:

BUG: KCSAN: data-race in fib6_clean_node / inet6_csk_route_socket

write to 0xffff88813df62e2c of 4 bytes by task 1920 on cpu 1:
 fib6_clean_node+0xc2/0x260 net/ipv6/ip6_fib.c:2178
 fib6_walk_continue+0x38e/0x430 net/ipv6/ip6_fib.c:2112
 fib6_walk net/ipv6/ip6_fib.c:2160 [inline]
 fib6_clean_tree net/ipv6/ip6_fib.c:2240 [inline]
 __fib6_clean_all+0x1a9/0x2e0 net/ipv6/ip6_fib.c:2256
 fib6_flush_trees+0x6c/0x80 net/ipv6/ip6_fib.c:2281
 rt_genid_bump_ipv6 include/net/net_namespace.h:488 [inline]
 addrconf_dad_completed+0x57f/0x870 net/ipv6/addrconf.c:4230
 addrconf_dad_work+0x908/0x1170
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:359
 ret_from_fork+0x1f/0x30

read to 0xffff88813df62e2c of 4 bytes by task 15701 on cpu 0:
 fib6_get_cookie_safe include/net/ip6_fib.h:285 [inline]
 rt6_get_cookie include/net/ip6_fib.h:306 [inline]
 ip6_dst_store include/net/ip6_route.h:234 [inline]
 inet6_csk_route_socket+0x352/0x3c0 net/ipv6/inet6_connection_sock.c:109
 inet6_csk_xmit+0x91/0x1e0 net/ipv6/inet6_connection_sock.c:121
 __tcp_transmit_skb+0x1323/0x1840 net/ipv4/tcp_output.c:1402
 tcp_transmit_skb net/ipv4/tcp_output.c:1420 [inline]
 tcp_write_xmit+0x1450/0x4460 net/ipv4/tcp_output.c:2680
 __tcp_push_pending_frames+0x68/0x1c0 net/ipv4/tcp_output.c:2864
 tcp_push+0x2d9/0x2f0 net/ipv4/tcp.c:725
 mptcp_push_release net/mptcp/protocol.c:1491 [inline]
 __mptcp_push_pending+0x46c/0x490 net/mptcp/protocol.c:1578
 mptcp_sendmsg+0x9ec/0xa50 net/mptcp/protocol.c:1764
 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:643
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 kernel_sendmsg+0x97/0xd0 net/socket.c:745
 sock_no_sendpage+0x84/0xb0 net/core/sock.c:3086
 inet_sendpage+0x9d/0xc0 net/ipv4/af_inet.c:834
 kernel_sendpage+0x187/0x200 net/socket.c:3492
 sock_sendpage+0x5a/0x70 net/socket.c:1007
 pipe_to_sendpage+0x128/0x160 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x207/0x500 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0x94/0xd0 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000026f -> 0x00000271

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15701 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

The Fixes tag I chose is probably arbitrary, I do not think
we need to backport this patch to older kernels.

Fixes: c5cff8561d2d ("ipv6: add rcu grace period before freeing fib6_node")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220120174112.1126644-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01 17:27:09 +01:00