Commit Graph

66562 Commits

Author SHA1 Message Date
Chuck Lever
0392dd51f9 SUNRPC: Per-rpc_clnt task PIDs
The current range of RPC task PIDs is 0..65535. That's not adequate
for distinguishing tasks across multiple rpc_clnts running high
throughput workloads.

To help relieve this situation and to reduce the bottleneck of
having a single atomic for assigning all RPC task PIDs, assign task
PIDs per rpc_clnt.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-10 11:05:54 +02:00
Trond Myklebust
33c3214bf4 SUNRPC: xprt_clear_locked() only needs release memory semantics
The clearing of the XPRT_LOCKED bit has to happen after we clear
xprt->snd_task, but we don't require any extra memory barriers after
that.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03 20:49:06 -04:00
Trond Myklebust
6dbcbe3f78 SUNRPC: Remove WQ_HIGHPRI from xprtiod
Don't let xprtiod pre-empt softirq.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03 20:49:05 -04:00
Trond Myklebust
47dd8796a3 SUNRPC: Add cond_resched() at the appropriate point in __rpc_execute()
Allow tasks that need to pre-empt rpciod/xprtiod to do so when it is
safe.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03 20:49:05 -04:00
Trond Myklebust
ea7a1019d8 SUNRPC: Partial revert of commit 6f9f17287e
The premise of commit 6f9f17287e ("SUNRPC: Mitigate cond_resched() in
xprt_transmit()") was that cond_resched() is expensive and unnecessary
when there has been just a single send.
The point of cond_resched() is to ensure that tasks that should pre-empt
this one get a chance to do so when it is safe to do so. The code prior
to commit 6f9f17287e failed to take into account that it was keeping a
rpc_task pinned for longer than it needed to, and so rather than doing a
full revert, let's just move the cond_resched.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-10-03 20:49:05 -04:00
Eric Dumazet
35306eb238 af_unix: fix races in sk_peer_pid and sk_peer_cred accesses
Jann Horn reported that SO_PEERCRED and SO_PEERGROUPS implementations
are racy, as af_unix can concurrently change sk_peer_pid and sk_peer_cred.

In order to fix this issue, this patch adds a new spinlock that needs
to be used whenever these fields are read or written.

Jann also pointed out that l2cap_sock_get_peer_pid_cb() is currently
reading sk->sk_peer_pid which makes no sense, as this field
is only possibly set by AF_UNIX sockets.
We will have to clean this in a separate patch.
This could be done by reverting b48596d1dc "Bluetooth: L2CAP: Add get_peer_pid callback"
or implementing what was truly expected.

Fixes: 109f6e39fa ("af_unix: Allow SO_PEERCRED to work across namespaces.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jann Horn <jannh@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 14:18:40 +01:00
Jakub Kicinski
a5b8fd6578 net: dev_addr_list: handle first address in __hw_addr_add_ex
struct dev_addr_list is used for device addresses, unicast addresses
and multicast addresses. The first of those needs special handling
of the main address - netdev->dev_addr points directly the data
of the entry and drivers write to it freely, so we can't maintain
it in the rbtree (for now, at least, to be fixed in net-next).

Current work around sprinkles special handling of the first
address on the list throughout the code but it missed the case
where address is being added. First address will not be visible
during subsequent adds.

Syzbot found a warning where unicast addresses are modified
without holding the rtnl lock, tl;dr is that team generates
the same modification multiple times, not necessarily when
right locks are held.

In the repro we have:

  macvlan -> team -> veth

macvlan adds a unicast address to the team. Team then pushes
that address down to its memebers (veths). Next something unrelated
makes team sync member addrs again, and because of the bug
the addr entries get duplicated in the veths. macvlan gets
removed, removes its addr from team which removes only one
of the duplicated addresses from veths. This removal is done
under rtnl. Next syzbot uses iptables to add a multicast addr
to team (which does not hold rtnl lock). Team syncs veth addrs,
but because veths' unicast list still has the duplicate it will
also get sync, even though this update is intended for mc addresses.
Again, uc address updates need rtnl lock, boom.

Reported-by: syzbot+7a2ab2cdc14d134de553@syzkaller.appspotmail.com
Fixes: 406f42fa0d ("net-next: When a bond have a massive amount of VLANs with IPv6 addresses, performance of changing link state, attaching a VRF, changing an IPv6 address, etc. go down dramtically.")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:29:09 +01:00
Vlad Buslov
d5ef190693 net: sched: flower: protect fl_walk() with rcu
Patch that refactored fl_walk() to use idr_for_each_entry_continue_ul()
also removed rcu protection of individual filters which causes following
use-after-free when filter is deleted concurrently. Fix fl_walk() to obtain
rcu read lock while iterating and taking the filter reference and temporary
release the lock while calling arg->fn() callback that can sleep.

KASAN trace:

[  352.773640] ==================================================================
[  352.775041] BUG: KASAN: use-after-free in fl_walk+0x159/0x240 [cls_flower]
[  352.776304] Read of size 4 at addr ffff8881c8251480 by task tc/2987

[  352.777862] CPU: 3 PID: 2987 Comm: tc Not tainted 5.15.0-rc2+ #2
[  352.778980] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[  352.781022] Call Trace:
[  352.781573]  dump_stack_lvl+0x46/0x5a
[  352.782332]  print_address_description.constprop.0+0x1f/0x140
[  352.783400]  ? fl_walk+0x159/0x240 [cls_flower]
[  352.784292]  ? fl_walk+0x159/0x240 [cls_flower]
[  352.785138]  kasan_report.cold+0x83/0xdf
[  352.785851]  ? fl_walk+0x159/0x240 [cls_flower]
[  352.786587]  kasan_check_range+0x145/0x1a0
[  352.787337]  fl_walk+0x159/0x240 [cls_flower]
[  352.788163]  ? fl_put+0x10/0x10 [cls_flower]
[  352.789007]  ? __mutex_unlock_slowpath.constprop.0+0x220/0x220
[  352.790102]  tcf_chain_dump+0x231/0x450
[  352.790878]  ? tcf_chain_tp_delete_empty+0x170/0x170
[  352.791833]  ? __might_sleep+0x2e/0xc0
[  352.792594]  ? tfilter_notify+0x170/0x170
[  352.793400]  ? __mutex_unlock_slowpath.constprop.0+0x220/0x220
[  352.794477]  tc_dump_tfilter+0x385/0x4b0
[  352.795262]  ? tc_new_tfilter+0x1180/0x1180
[  352.796103]  ? __mod_node_page_state+0x1f/0xc0
[  352.796974]  ? __build_skb_around+0x10e/0x130
[  352.797826]  netlink_dump+0x2c0/0x560
[  352.798563]  ? netlink_getsockopt+0x430/0x430
[  352.799433]  ? __mutex_unlock_slowpath.constprop.0+0x220/0x220
[  352.800542]  __netlink_dump_start+0x356/0x440
[  352.801397]  rtnetlink_rcv_msg+0x3ff/0x550
[  352.802190]  ? tc_new_tfilter+0x1180/0x1180
[  352.802872]  ? rtnl_calcit.isra.0+0x1f0/0x1f0
[  352.803668]  ? tc_new_tfilter+0x1180/0x1180
[  352.804344]  ? _copy_from_iter_nocache+0x800/0x800
[  352.805202]  ? kasan_set_track+0x1c/0x30
[  352.805900]  netlink_rcv_skb+0xc6/0x1f0
[  352.806587]  ? rht_deferred_worker+0x6b0/0x6b0
[  352.807455]  ? rtnl_calcit.isra.0+0x1f0/0x1f0
[  352.808324]  ? netlink_ack+0x4d0/0x4d0
[  352.809086]  ? netlink_deliver_tap+0x62/0x3d0
[  352.809951]  netlink_unicast+0x353/0x480
[  352.810744]  ? netlink_attachskb+0x430/0x430
[  352.811586]  ? __alloc_skb+0xd7/0x200
[  352.812349]  netlink_sendmsg+0x396/0x680
[  352.813132]  ? netlink_unicast+0x480/0x480
[  352.813952]  ? __import_iovec+0x192/0x210
[  352.814759]  ? netlink_unicast+0x480/0x480
[  352.815580]  sock_sendmsg+0x6c/0x80
[  352.816299]  ____sys_sendmsg+0x3a5/0x3c0
[  352.817096]  ? kernel_sendmsg+0x30/0x30
[  352.817873]  ? __ia32_sys_recvmmsg+0x150/0x150
[  352.818753]  ___sys_sendmsg+0xd8/0x140
[  352.819518]  ? sendmsg_copy_msghdr+0x110/0x110
[  352.820402]  ? ___sys_recvmsg+0xf4/0x1a0
[  352.821110]  ? __copy_msghdr_from_user+0x260/0x260
[  352.821934]  ? _raw_spin_lock+0x81/0xd0
[  352.822680]  ? __handle_mm_fault+0xef3/0x1b20
[  352.823549]  ? rb_insert_color+0x2a/0x270
[  352.824373]  ? copy_page_range+0x16b0/0x16b0
[  352.825209]  ? perf_event_update_userpage+0x2d0/0x2d0
[  352.826190]  ? __fget_light+0xd9/0xf0
[  352.826941]  __sys_sendmsg+0xb3/0x130
[  352.827613]  ? __sys_sendmsg_sock+0x20/0x20
[  352.828377]  ? do_user_addr_fault+0x2c5/0x8a0
[  352.829184]  ? fpregs_assert_state_consistent+0x52/0x60
[  352.830001]  ? exit_to_user_mode_prepare+0x32/0x160
[  352.830845]  do_syscall_64+0x35/0x80
[  352.831445]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  352.832331] RIP: 0033:0x7f7bee973c17
[  352.833078] Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
[  352.836202] RSP: 002b:00007ffcbb368e28 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  352.837524] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7bee973c17
[  352.838715] RDX: 0000000000000000 RSI: 00007ffcbb368e50 RDI: 0000000000000003
[  352.839838] RBP: 00007ffcbb36d090 R08: 00000000cea96d79 R09: 00007f7beea34a40
[  352.841021] R10: 00000000004059bb R11: 0000000000000246 R12: 000000000046563f
[  352.842208] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcbb36d088

[  352.843784] Allocated by task 2960:
[  352.844451]  kasan_save_stack+0x1b/0x40
[  352.845173]  __kasan_kmalloc+0x7c/0x90
[  352.845873]  fl_change+0x282/0x22db [cls_flower]
[  352.846696]  tc_new_tfilter+0x6cf/0x1180
[  352.847493]  rtnetlink_rcv_msg+0x471/0x550
[  352.848323]  netlink_rcv_skb+0xc6/0x1f0
[  352.849097]  netlink_unicast+0x353/0x480
[  352.849886]  netlink_sendmsg+0x396/0x680
[  352.850678]  sock_sendmsg+0x6c/0x80
[  352.851398]  ____sys_sendmsg+0x3a5/0x3c0
[  352.852202]  ___sys_sendmsg+0xd8/0x140
[  352.852967]  __sys_sendmsg+0xb3/0x130
[  352.853718]  do_syscall_64+0x35/0x80
[  352.854457]  entry_SYSCALL_64_after_hwframe+0x44/0xae

[  352.855830] Freed by task 7:
[  352.856421]  kasan_save_stack+0x1b/0x40
[  352.857139]  kasan_set_track+0x1c/0x30
[  352.857854]  kasan_set_free_info+0x20/0x30
[  352.858609]  __kasan_slab_free+0xed/0x130
[  352.859348]  kfree+0xa7/0x3c0
[  352.859951]  process_one_work+0x44d/0x780
[  352.860685]  worker_thread+0x2e2/0x7e0
[  352.861390]  kthread+0x1f4/0x220
[  352.862022]  ret_from_fork+0x1f/0x30

[  352.862955] Last potentially related work creation:
[  352.863758]  kasan_save_stack+0x1b/0x40
[  352.864378]  kasan_record_aux_stack+0xab/0xc0
[  352.865028]  insert_work+0x30/0x160
[  352.865617]  __queue_work+0x351/0x670
[  352.866261]  rcu_work_rcufn+0x30/0x40
[  352.866917]  rcu_core+0x3b2/0xdb0
[  352.867561]  __do_softirq+0xf6/0x386

[  352.868708] Second to last potentially related work creation:
[  352.869779]  kasan_save_stack+0x1b/0x40
[  352.870560]  kasan_record_aux_stack+0xab/0xc0
[  352.871426]  call_rcu+0x5f/0x5c0
[  352.872108]  queue_rcu_work+0x44/0x50
[  352.872855]  __fl_put+0x17c/0x240 [cls_flower]
[  352.873733]  fl_delete+0xc7/0x100 [cls_flower]
[  352.874607]  tc_del_tfilter+0x510/0xb30
[  352.886085]  rtnetlink_rcv_msg+0x471/0x550
[  352.886875]  netlink_rcv_skb+0xc6/0x1f0
[  352.887636]  netlink_unicast+0x353/0x480
[  352.888285]  netlink_sendmsg+0x396/0x680
[  352.888942]  sock_sendmsg+0x6c/0x80
[  352.889583]  ____sys_sendmsg+0x3a5/0x3c0
[  352.890311]  ___sys_sendmsg+0xd8/0x140
[  352.891019]  __sys_sendmsg+0xb3/0x130
[  352.891716]  do_syscall_64+0x35/0x80
[  352.892395]  entry_SYSCALL_64_after_hwframe+0x44/0xae

[  352.893666] The buggy address belongs to the object at ffff8881c8251000
                which belongs to the cache kmalloc-2k of size 2048
[  352.895696] The buggy address is located 1152 bytes inside of
                2048-byte region [ffff8881c8251000, ffff8881c8251800)
[  352.897640] The buggy address belongs to the page:
[  352.898492] page:00000000213bac35 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c8250
[  352.900110] head:00000000213bac35 order:3 compound_mapcount:0 compound_pincount:0
[  352.901541] flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff)
[  352.902908] raw: 002ffff800010200 0000000000000000 dead000000000122 ffff888100042f00
[  352.904391] raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
[  352.905861] page dumped because: kasan: bad access detected

[  352.907323] Memory state around the buggy address:
[  352.908218]  ffff8881c8251380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  352.909471]  ffff8881c8251400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  352.910735] >ffff8881c8251480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  352.912012]                    ^
[  352.912642]  ffff8881c8251500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  352.913919]  ffff8881c8251580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  352.915185] ==================================================================

Fixes: d39d714969 ("idr: introduce idr_for_each_entry_continue_ul()")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:20:31 +01:00
Paolo Abeni
4905455628 net: introduce and use lock_sock_fast_nested()
Syzkaller reported a false positive deadlock involving
the nl socket lock and the subflow socket lock:

MPTCP: kernel_bind error, err=-98
============================================
WARNING: possible recursive locking detected
5.15.0-rc1-syzkaller #0 Not tainted
--------------------------------------------
syz-executor998/6520 is trying to acquire lock:
ffff8880795718a0 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738

but task is already holding lock:
ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline]
ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(k-sk_lock-AF_INET);
  lock(k-sk_lock-AF_INET);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz-executor998/6520:
 #0: ffffffff8d176c50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x3e0/0x580 net/netlink/genetlink.c:790
 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline]
 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720

stack backtrace:
CPU: 1 PID: 6520 Comm: syz-executor998 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2944 [inline]
 check_deadlock kernel/locking/lockdep.c:2987 [inline]
 validate_chain kernel/locking/lockdep.c:3776 [inline]
 __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 lock_sock_fast+0x36/0x100 net/core/sock.c:3229
 mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431
 __sock_release net/socket.c:649 [inline]
 sock_release+0x87/0x1b0 net/socket.c:677
 mptcp_pm_nl_create_listen_socket+0x238/0x2c0 net/mptcp/pm_netlink.c:900
 mptcp_nl_cmd_add_addr+0x359/0x930 net/mptcp/pm_netlink.c:1170
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_no_sendpage+0x101/0x150 net/core/sock.c:2980
 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3504
 kernel_sendpage net/socket.c:3501 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:1003
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x110/0x180 fs/splice.c:936
 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891
 do_splice_direct+0x1b3/0x280 fs/splice.c:979
 do_sendfile+0xae9/0x1240 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1300
 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: 0033:0x7f215cb69969
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc96bb3868 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f215cbad072 RCX: 00007f215cb69969
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007ffc96bb3a08 R09: 00007ffc96bb3a08
R10: 0000000100000002 R11: 0000000000000246 R12: 00007ffc96bb387c
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000

the problem originates from uncorrect lock annotation in the mptcp
code and is only visible since commit 2dcb96bacc ("net: core: Correct
the sock::sk_lock.owned lockdep annotations"), but is present since
the port-based endpoint support initial implementation.

This patch addresses the issue introducing a nested variant of
lock_sock_fast() and using it in the relevant code path.

Fixes: 1729cf186d ("mptcp: create the listening socket for new port")
Fixes: 2dcb96bacc ("net: core: Correct the sock::sk_lock.owned lockdep annotations")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Reported-and-tested-by: syzbot+1dd53f7a89b299d59eaf@syzkaller.appspotmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:06:47 +01:00
Thomas Gleixner
f936bb42ae net: bridge: mcast: Associate the seqcount with its protecting lock.
The sequence count bridge_mcast_querier::seq is protected by
net_bridge::multicast_lock but seqcount_init() does not associate the
seqcount with the lock. This leads to a warning on PREEMPT_RT because
preemption is still enabled.

Let seqcount_init() associate the seqcount with lock that protects the
write section. Remove lockdep_assert_held_once() because lockdep already checks
whether the associated lock is held.

Fixes: 67b746f94f ("net: bridge: mcast: make sure querier port/address updates are consistent")
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Mike Galbraith <efault@gmx.de>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Link: https://lore.kernel.org/r/20210928141049.593833-1-bigeasy@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-28 17:30:36 -07:00
David S. Miller
4ccb9f03fe Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2021-09-28

The following pull-request contains BPF updates for your *net* tree.

We've added 10 non-merge commits during the last 14 day(s) which contain
a total of 11 files changed, 139 insertions(+), 53 deletions(-).

The main changes are:

1) Fix MIPS JIT jump code emission for too large offsets, from Piotr Krysiuk.

2) Fix x86 JIT atomic/fetch emission when dst reg maps to rax, from Johan Almbladh.

3) Fix cgroup_sk_alloc corner case when called from interrupt, from Daniel Borkmann.

4) Fix segfault in libbpf's linker for objects without BTF, from Kumar Kartikeya Dwivedi.

5) Fix bpf_jit_charge_modmem for applications with CAP_BPF, from Lorenz Bauer.

6) Fix return value handling for struct_ops BPF programs, from Hou Tao.

7) Various fixes to BPF selftests, from Jiri Benc.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
,
2021-09-28 13:52:46 +01:00
Kuniyuki Iwashima
f4bd73b5a9 af_unix: Return errno instead of NULL in unix_create1().
unix_create1() returns NULL on error, and the callers assume that it never
fails for reasons other than out of memory.  So, the callers always return
-ENOMEM when unix_create1() fails.

However, it also returns NULL when the number of af_unix sockets exceeds
twice the limit controlled by sysctl: fs.file-max.  In this case, the
callers should return -ENFILE like alloc_empty_file().

This patch changes unix_create1() to return the correct error value instead
of NULL on error.

Out of curiosity, the assumption has been wrong since 1999 due to this
change introduced in 2.2.4 [0].

  diff -u --recursive --new-file v2.2.3/linux/net/unix/af_unix.c linux/net/unix/af_unix.c
  --- v2.2.3/linux/net/unix/af_unix.c	Tue Jan 19 11:32:53 1999
  +++ linux/net/unix/af_unix.c	Sun Mar 21 07:22:00 1999
  @@ -388,6 +413,9 @@
   {
   	struct sock *sk;

  +	if (atomic_read(&unix_nr_socks) >= 2*max_files)
  +		return NULL;
  +
   	MOD_INC_USE_COUNT;
   	sk = sk_alloc(PF_UNIX, GFP_KERNEL, 1);
   	if (!sk) {

[0]: https://cdn.kernel.org/pub/linux/kernel/v2.2/patch-2.2.4.gz

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-28 13:22:57 +01:00
Eric Dumazet
a9f5970767 net: udp: annotate data race around udp_sk(sk)->corkflag
up->corkflag field can be read or written without any lock.
Annotate accesses to avoid possible syzbot/KCSAN reports.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-28 13:21:16 +01:00
Daniel Borkmann
435b08ec00 bpf, test, cgroup: Use sk_{alloc,free} for test cases
BPF test infra has some hacks in place which kzalloc() a socket and perform
minimum init via sock_net_set() and sock_init_data(). As a result, the sk's
skcd->cgroup is NULL since it didn't go through proper initialization as it
would have been the case from sk_alloc(). Rather than re-adding a NULL test
in sock_cgroup_ptr() just for this, use sk_{alloc,free}() pair for the test
socket. The latter also allows to get rid of the bpf_sk_storage_free() special
case.

Fixes: 8520e224f5 ("bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode")
Fixes: b7a1848e83 ("bpf: add BPF_PROG_TEST_RUN support for flow dissector")
Fixes: 2cb494a36c ("bpf: add tests for direct packet access from CGROUP_SKB")
Reported-by: syzbot+664b58e9a40fbb2cec71@syzkaller.appspotmail.com
Reported-by: syzbot+33f36d0754d4c5c0e102@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: syzbot+664b58e9a40fbb2cec71@syzkaller.appspotmail.com
Tested-by: syzbot+33f36d0754d4c5c0e102@syzkaller.appspotmail.com
Link: https://lore.kernel.org/bpf/20210927123921.21535-2-daniel@iogearbox.net
2021-09-28 09:29:28 +02:00
David S. Miller
ca48aa4ab8 Some fixes:
* potential use-after-free in CCMP/GCMP RX processing
  * potential use-after-free in TX A-MSDU processing
  * revert to low data rates for no-ack as the commit
    broke other things
  * limit VHT MCS/NSS in radiotap injection
  * drop frames with invalid addresses in IBSS mode
  * check rhashtable_init() return value in mesh
  * fix potentially unaligned access in mesh
  * fix late beacon hrtimer handling in hwsim (syzbot)
  * fix documentation for PTK0 rekeying
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Merge tag 'mac80211-for-net-2021-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes berg says:

====================
Some fixes:
 * potential use-after-free in CCMP/GCMP RX processing
 * potential use-after-free in TX A-MSDU processing
 * revert to low data rates for no-ack as the commit
   broke other things
 * limit VHT MCS/NSS in radiotap injection
 * drop frames with invalid addresses in IBSS mode
 * check rhashtable_init() return value in mesh
 * fix potentially unaligned access in mesh
 * fix late beacon hrtimer handling in hwsim (syzbot)
 * fix documentation for PTK0 rekeying
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-27 13:39:39 +01:00
MichelleJin
111461d573 mac80211: check return value of rhashtable_init
When rhashtable_init() fails, it returns -EINVAL.
However, since error return value of rhashtable_init is not checked,
it can cause use of uninitialized pointers.
So, fix unhandled errors of rhashtable_init.

Signed-off-by: MichelleJin <shjy180909@gmail.com>
Link: https://lore.kernel.org/r/20210927033457.1020967-4-shjy180909@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-27 12:00:34 +02:00
Johannes Berg
94513069eb mac80211: fix use-after-free in CCMP/GCMP RX
When PN checking is done in mac80211, for fragmentation we need
to copy the PN to the RX struct so we can later use it to do a
comparison, since commit bf30ca922a ("mac80211: check defrag
PN against current frame").

Unfortunately, in that commit I used the 'hdr' variable without
it being necessarily valid, so use-after-free could occur if it
was necessary to reallocate (parts of) the frame.

Fix this by reloading the variable after the code that results
in the reallocations, if any.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=214401.

Cc: stable@vger.kernel.org
Fixes: bf30ca922a ("mac80211: check defrag PN against current frame")
Link: https://lore.kernel.org/r/20210927115838.12b9ac6bb233.I1d066acd5408a662c3b6e828122cd314fcb28cdb@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-27 11:59:49 +02:00
王贇
b193e15ac6 net: prevent user from passing illegal stab size
We observed below report when playing with netlink sock:

  UBSAN: shift-out-of-bounds in net/sched/sch_api.c:580:10
  shift exponent 249 is too large for 32-bit type
  CPU: 0 PID: 685 Comm: a.out Not tainted
  Call Trace:
   dump_stack_lvl+0x8d/0xcf
   ubsan_epilogue+0xa/0x4e
   __ubsan_handle_shift_out_of_bounds+0x161/0x182
   __qdisc_calculate_pkt_len+0xf0/0x190
   __dev_queue_xmit+0x2ed/0x15b0

it seems like kernel won't check the stab log value passing from
user, and will use the insane value later to calculate pkt_len.

This patch just add a check on the size/cell_log to avoid insane
calculation.

Reported-by: Abaci <abaci@linux.alibaba.com>
Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-26 11:09:07 +01:00
Jakub Kicinski
7fe7f3182a Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

1) ipset limits the max allocatable memory via kvmalloc() to MAX_INT,
   from Jozsef Kadlecsik.

2) Check ip_vs_conn_tab_bits value to be in the range specified
   in Kconfig, from Andrea Claudi.

3) Initialize fragment offset in ip6tables, from Jeremy Sowden.

4) Make conntrack hash chain length random, from Florian Westphal.

5) Add zone ID to conntrack and NAT hashtuple again, also from Florian.

6) Add selftests for bidirectional zone support and colliding tuples,
   from Florian Westphal.

7) Unlink table before synchronize_rcu when cleaning tables with
   owner, from Florian.

8) ipset limits the max allocatable memory via kvmalloc() to MAX_INT.

9) Release conntrack entries via workqueue in masquerade, from Florian.

10) Fix bogus net_init in iptables raw table definition, also from Florian.

11) Work around missing softdep in log extensions, from Florian Westphal.

12) Serialize hash resizes and cleanups with mutex, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf:
  netfilter: conntrack: serialize hash resizes and cleanups
  netfilter: log: work around missing softdep backend module
  netfilter: iptable_raw: drop bogus net_init annotation
  netfilter: nf_nat_masquerade: defer conntrack walk to work queue
  netfilter: nf_nat_masquerade: make async masq_inet6_event handling generic
  netfilter: nf_tables: Fix oversized kvmalloc() calls
  netfilter: nf_tables: unlink table before deleting it
  selftests: netfilter: add zone stress test with colliding tuples
  selftests: netfilter: add selftest for directional zone support
  netfilter: nat: include zone id in nat table hash again
  netfilter: conntrack: include zone id in tuple hash again
  netfilter: conntrack: make max chain length random
  netfilter: ip6_tables: zero-initialize fragment offset
  ipvs: check that ip_vs_conn_tab_bits is between 8 and 20
  netfilter: ipset: Fix oversized kvmalloc() calls
====================

Link: https://lore.kernel.org/r/20210924221113.348767-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-24 17:27:20 -07:00
Xiao Liang
597aa16c78 net: ipv4: Fix rtnexthop len when RTA_FLOW is present
Multipath RTA_FLOW is embedded in nexthop. Dump it in fib_add_nexthop()
to get the length of rtnexthop correct.

Fixes: b0f6019363 ("ipv4: Refactor nexthop attributes in fib_dump_info")
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 14:07:10 +01:00
Davide Caratti
3f4a08909e mptcp: allow changing the 'backup' bit when no sockets are open
current Linux refuses to change the 'backup' bit of MPTCP endpoints, i.e.
using MPTCP_PM_CMD_SET_FLAGS, unless it finds (at least) one subflow that
matches the endpoint address. There is no reason for that, so we can just
ignore the return value of mptcp_nl_addr_backup(). In this way, endpoints
can reconfigure their 'backup' flag even if no MPTCP sockets are open (or
more generally, in case the MP_PRIO message is not sent out).

Fixes: 0f9f696a50 ("mptcp: add set_flags command in PM netlink")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 10:51:36 +01:00
Florian Westphal
ea1300b9df mptcp: don't return sockets in foreign netns
mptcp_token_get_sock() may return a mptcp socket that is in
a different net namespace than the socket that received the token value.

The mptcp syncookie code path had an explicit check for this,
this moves the test into mptcp_token_get_sock() function.

Eventually token.c should be converted to pernet storage, but
such change is not suitable for net tree.

Fixes: 2c5ebd001d ("mptcp: refactor token container")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 10:51:36 +01:00
Xin Long
f7e745f8e9 sctp: break out if skb_header_pointer returns NULL in sctp_rcv_ootb
We should always check if skb_header_pointer's return is NULL before
using it, otherwise it may cause null-ptr-deref, as syzbot reported:

  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
  RIP: 0010:sctp_rcv_ootb net/sctp/input.c:705 [inline]
  RIP: 0010:sctp_rcv+0x1d84/0x3220 net/sctp/input.c:196
  Call Trace:
  <IRQ>
   sctp6_rcv+0x38/0x60 net/sctp/ipv6.c:1109
   ip6_protocol_deliver_rcu+0x2e9/0x1ca0 net/ipv6/ip6_input.c:422
   ip6_input_finish+0x62/0x170 net/ipv6/ip6_input.c:463
   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:472
   dst_input include/net/dst.h:460 [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+0x28c/0x3c0 net/ipv6/ip6_input.c:297

Fixes: 3acb50c18d ("sctp: delay as much as possible skb_linearize")
Reported-by: syzbot+581aff2ae6b860625116@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 10:36:19 +01:00
Ido Schimmel
3106a08475 nexthop: Fix memory leaks in nexthop notification chain listeners
syzkaller discovered memory leaks [1] that can be reduced to the
following commands:

 # ip nexthop add id 1 blackhole
 # devlink dev reload pci/0000:06:00.0

As part of the reload flow, mlxsw will unregister its netdevs and then
unregister from the nexthop notification chain. Before unregistering
from the notification chain, mlxsw will receive delete notifications for
nexthop objects using netdevs registered by mlxsw or their uppers. mlxsw
will not receive notifications for nexthops using netdevs that are not
dismantled as part of the reload flow. For example, the blackhole
nexthop above that internally uses the loopback netdev as its nexthop
device.

One way to fix this problem is to have listeners flush their nexthop
tables after unregistering from the notification chain. This is
error-prone as evident by this patch and also not symmetric with the
registration path where a listener receives a dump of all the existing
nexthops.

Therefore, fix this problem by replaying delete notifications for the
listener being unregistered. This is symmetric to the registration path
and also consistent with the netdev notification chain.

The above means that unregister_nexthop_notifier(), like
register_nexthop_notifier(), will have to take RTNL in order to iterate
over the existing nexthops and that any callers of the function cannot
hold RTNL. This is true for mlxsw and netdevsim, but not for the VXLAN
driver. To avoid a deadlock, change the latter to unregister its nexthop
listener without holding RTNL, making it symmetric to the registration
path.

[1]
unreferenced object 0xffff88806173d600 (size 512):
  comm "syz-executor.0", pid 1290, jiffies 4295583142 (age 143.507s)
  hex dump (first 32 bytes):
    41 9d 1e 60 80 88 ff ff 08 d6 73 61 80 88 ff ff  A..`......sa....
    08 d6 73 61 80 88 ff ff 01 00 00 00 00 00 00 00  ..sa............
  backtrace:
    [<ffffffff81a6b576>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<ffffffff81a6b576>] slab_post_alloc_hook+0x96/0x490 mm/slab.h:522
    [<ffffffff81a716d3>] slab_alloc_node mm/slub.c:3206 [inline]
    [<ffffffff81a716d3>] slab_alloc mm/slub.c:3214 [inline]
    [<ffffffff81a716d3>] kmem_cache_alloc_trace+0x163/0x370 mm/slub.c:3231
    [<ffffffff82e8681a>] kmalloc include/linux/slab.h:591 [inline]
    [<ffffffff82e8681a>] kzalloc include/linux/slab.h:721 [inline]
    [<ffffffff82e8681a>] mlxsw_sp_nexthop_obj_group_create drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:4918 [inline]
    [<ffffffff82e8681a>] mlxsw_sp_nexthop_obj_new drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:5054 [inline]
    [<ffffffff82e8681a>] mlxsw_sp_nexthop_obj_event+0x59a/0x2910 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c:5239
    [<ffffffff813ef67d>] notifier_call_chain+0xbd/0x210 kernel/notifier.c:83
    [<ffffffff813f0662>] blocking_notifier_call_chain kernel/notifier.c:318 [inline]
    [<ffffffff813f0662>] blocking_notifier_call_chain+0x72/0xa0 kernel/notifier.c:306
    [<ffffffff8384b9c6>] call_nexthop_notifiers+0x156/0x310 net/ipv4/nexthop.c:244
    [<ffffffff83852bd8>] insert_nexthop net/ipv4/nexthop.c:2336 [inline]
    [<ffffffff83852bd8>] nexthop_add net/ipv4/nexthop.c:2644 [inline]
    [<ffffffff83852bd8>] rtm_new_nexthop+0x14e8/0x4d10 net/ipv4/nexthop.c:2913
    [<ffffffff833e9a78>] rtnetlink_rcv_msg+0x448/0xbf0 net/core/rtnetlink.c:5572
    [<ffffffff83608703>] netlink_rcv_skb+0x173/0x480 net/netlink/af_netlink.c:2504
    [<ffffffff833de032>] rtnetlink_rcv+0x22/0x30 net/core/rtnetlink.c:5590
    [<ffffffff836069de>] netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
    [<ffffffff836069de>] netlink_unicast+0x5ae/0x7f0 net/netlink/af_netlink.c:1340
    [<ffffffff83607501>] netlink_sendmsg+0x8e1/0xe30 net/netlink/af_netlink.c:1929
    [<ffffffff832fde84>] sock_sendmsg_nosec net/socket.c:704 [inline]
    [<ffffffff832fde84>] sock_sendmsg net/socket.c:724 [inline]
    [<ffffffff832fde84>] ____sys_sendmsg+0x874/0x9f0 net/socket.c:2409
    [<ffffffff83304a44>] ___sys_sendmsg+0x104/0x170 net/socket.c:2463
    [<ffffffff83304c01>] __sys_sendmsg+0x111/0x1f0 net/socket.c:2492
    [<ffffffff83304d5d>] __do_sys_sendmsg net/socket.c:2501 [inline]
    [<ffffffff83304d5d>] __se_sys_sendmsg net/socket.c:2499 [inline]
    [<ffffffff83304d5d>] __x64_sys_sendmsg+0x7d/0xc0 net/socket.c:2499

Fixes: 2a014b200b ("mlxsw: spectrum_router: Add support for nexthop objects")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-23 12:33:22 +01:00
Johannes Berg
b9731062ce mac80211: mesh: fix potentially unaligned access
The pointer here points directly into the frame, so the
access is potentially unaligned. Use get_unaligned_le16
to avoid that.

Fixes: 3f52b7e328 ("mac80211: mesh power save basics")
Link: https://lore.kernel.org/r/20210920154009.3110ff75be0c.Ib6a2ff9e9cc9bc6fca50fce631ec1ce725cc926b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-23 13:25:09 +02:00
Lorenzo Bianconi
13cb6d826e mac80211: limit injected vht mcs/nss in ieee80211_parse_tx_radiotap
Limit max values for vht mcs and nss in ieee80211_parse_tx_radiotap
routine in order to fix the following warning reported by syzbot:

WARNING: CPU: 0 PID: 10717 at include/net/mac80211.h:989 ieee80211_rate_set_vht include/net/mac80211.h:989 [inline]
WARNING: CPU: 0 PID: 10717 at include/net/mac80211.h:989 ieee80211_parse_tx_radiotap+0x101e/0x12d0 net/mac80211/tx.c:2244
Modules linked in:
CPU: 0 PID: 10717 Comm: syz-executor.5 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ieee80211_rate_set_vht include/net/mac80211.h:989 [inline]
RIP: 0010:ieee80211_parse_tx_radiotap+0x101e/0x12d0 net/mac80211/tx.c:2244
RSP: 0018:ffffc9000186f3e8 EFLAGS: 00010216
RAX: 0000000000000618 RBX: ffff88804ef76500 RCX: ffffc900143a5000
RDX: 0000000000040000 RSI: ffffffff888f478e RDI: 0000000000000003
RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000100
R10: ffffffff888f46f9 R11: 0000000000000000 R12: 00000000fffffff8
R13: ffff88804ef7653c R14: 0000000000000001 R15: 0000000000000004
FS:  00007fbf5718f700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2de23000 CR3: 000000006a671000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 ieee80211_monitor_select_queue+0xa6/0x250 net/mac80211/iface.c:740
 netdev_core_pick_tx+0x169/0x2e0 net/core/dev.c:4089
 __dev_queue_xmit+0x6f9/0x3710 net/core/dev.c:4165
 __bpf_tx_skb net/core/filter.c:2114 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2139 [inline]
 __bpf_redirect+0x5ba/0xd20 net/core/filter.c:2162
 ____bpf_clone_redirect net/core/filter.c:2429 [inline]
 bpf_clone_redirect+0x2ae/0x420 net/core/filter.c:2401
 bpf_prog_eeb6f53a69e5c6a2+0x59/0x234
 bpf_dispatcher_nop_func include/linux/bpf.h:717 [inline]
 __bpf_prog_run include/linux/filter.h:624 [inline]
 bpf_prog_run include/linux/filter.h:631 [inline]
 bpf_test_run+0x381/0xa30 net/bpf/test_run.c:119
 bpf_prog_test_run_skb+0xb84/0x1ee0 net/bpf/test_run.c:663
 bpf_prog_test_run kernel/bpf/syscall.c:3307 [inline]
 __sys_bpf+0x2137/0x5df0 kernel/bpf/syscall.c:4605
 __do_sys_bpf kernel/bpf/syscall.c:4691 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4689 [inline]
 __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4689
 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: 0033:0x4665f9

Reported-by: syzbot+0196ac871673f0c20f68@syzkaller.appspotmail.com
Fixes: 646e76bb5d ("mac80211: parse VHT info in injected frames")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/c26c3f02dcb38ab63b2f2534cb463d95ee81bb13.1632141760.git.lorenzo@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-23 13:22:57 +02:00
YueHaibing
a6555f8445 mac80211: Drop frames from invalid MAC address in ad-hoc mode
WARNING: CPU: 1 PID: 9 at net/mac80211/sta_info.c:554
sta_info_insert_rcu+0x121/0x12a0
Modules linked in:
CPU: 1 PID: 9 Comm: kworker/u8:1 Not tainted 5.14.0-rc7+ #253
Workqueue: phy3 ieee80211_iface_work
RIP: 0010:sta_info_insert_rcu+0x121/0x12a0
...
Call Trace:
 ieee80211_ibss_finish_sta+0xbc/0x170
 ieee80211_ibss_work+0x13f/0x7d0
 ieee80211_iface_work+0x37a/0x500
 process_one_work+0x357/0x850
 worker_thread+0x41/0x4d0

If an Ad-Hoc node receives packets with invalid source MAC address,
it hits a WARN_ON in sta_info_insert_check(), this can spam the log.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20210827144230.39944-1-yuehaibing@huawei.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-23 13:05:38 +02:00
Chih-Kang Chang
fe94bac626 mac80211: Fix ieee80211_amsdu_aggregate frag_tail bug
In ieee80211_amsdu_aggregate() set a pointer frag_tail point to the
end of skb_shinfo(head)->frag_list, and use it to bind other skb in
the end of this function. But when execute ieee80211_amsdu_aggregate()
->ieee80211_amsdu_realloc_pad()->pskb_expand_head(), the address of
skb_shinfo(head)->frag_list will be changed. However, the
ieee80211_amsdu_aggregate() not update frag_tail after call
pskb_expand_head(). That will cause the second skb can't bind to the
head skb appropriately.So we update the address of frag_tail to fix it.

Fixes: 6e0456b545 ("mac80211: add A-MSDU tx support")
Signed-off-by: Chih-Kang Chang <gary.chang@realtek.com>
Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://lore.kernel.org/r/20210830073240.12736-1-pkshih@realtek.com
[reword comment]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-23 13:04:35 +02:00
Felix Fietkau
98d46b021f Revert "mac80211: do not use low data rates for data frames with no ack flag"
This reverts commit d333322361 ("mac80211: do not use low data rates for
data frames with no ack flag").

Returning false early in rate_control_send_low breaks sending broadcast
packets, since rate control will not select a rate for it.

Before re-introducing a fixed version of this patch, we should probably also
make some changes to rate control to be more conservative in selecting rates
for no-ack packets and also prevent using probing rates on them, since we won't
get any feedback.

Fixes: d333322361 ("mac80211: do not use low data rates for data frames with no ack flag")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20210906083559.9109-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-09-23 12:59:29 +02:00
Paolo Abeni
977d293e23 mptcp: ensure tx skbs always have the MPTCP ext
Due to signed/unsigned comparison, the expression:

	info->size_goal - skb->len > 0

evaluates to true when the size goal is smaller than the
skb size. That results in lack of tx cache refill, so that
the skb allocated by the core TCP code lacks the required
MPTCP skb extensions.

Due to the above, syzbot is able to trigger the following WARN_ON():

WARNING: CPU: 1 PID: 810 at net/mptcp/protocol.c:1366 mptcp_sendmsg_frag+0x1362/0x1bc0 net/mptcp/protocol.c:1366
Modules linked in:
CPU: 1 PID: 810 Comm: syz-executor.4 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mptcp_sendmsg_frag+0x1362/0x1bc0 net/mptcp/protocol.c:1366
Code: ff 4c 8b 74 24 50 48 8b 5c 24 58 e9 0f fb ff ff e8 13 44 8b f8 4c 89 e7 45 31 ed e8 98 57 2e fe e9 81 f4 ff ff e8 fe 43 8b f8 <0f> 0b 41 bd ea ff ff ff e9 6f f4 ff ff 4c 89 e7 e8 b9 8e d2 f8 e9
RSP: 0018:ffffc9000531f6a0 EFLAGS: 00010216
RAX: 000000000000697f RBX: 0000000000000000 RCX: ffffc90012107000
RDX: 0000000000040000 RSI: ffffffff88eac9e2 RDI: 0000000000000003
RBP: ffff888078b15780 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88eac017 R11: 0000000000000000 R12: ffff88801de0a280
R13: 0000000000006b58 R14: ffff888066278280 R15: ffff88803c2fe9c0
FS:  00007fd9f866e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faebcb2f718 CR3: 00000000267cb000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __mptcp_push_pending+0x1fb/0x6b0 net/mptcp/protocol.c:1547
 mptcp_release_cb+0xfe/0x210 net/mptcp/protocol.c:3003
 release_sock+0xb4/0x1b0 net/core/sock.c:3206
 sk_stream_wait_memory+0x604/0xed0 net/core/stream.c:145
 mptcp_sendmsg+0xc39/0x1bc0 net/mptcp/protocol.c:1749
 inet6_sendmsg+0x99/0xe0 net/ipv6/af_inet6.c:643
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_write_iter+0x2a0/0x3e0 net/socket.c:1057
 call_write_iter include/linux/fs.h:2163 [inline]
 new_sync_write+0x40b/0x640 fs/read_write.c:507
 vfs_write+0x7cf/0xae0 fs/read_write.c:594
 ksys_write+0x1ee/0x250 fs/read_write.c:647
 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: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd9f866e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665f9
RDX: 00000000000e7b78 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 0000000000a9fb1f R14: 00007fd9f866e300 R15: 0000000000022000

Fix the issue rewriting the relevant expression to avoid
sign-related problems - note: size_goal is always >= 0.

Additionally, ensure that the skb in the tx cache always carries
the relevant extension.

Reported-and-tested-by: syzbot+263a248eec3e875baa7b@syzkaller.appspotmail.com
Fixes: 1094c6fe72 ("mptcp: fix possible divide by zero")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-22 14:39:41 +01:00
Vladimir Oltean
5135e96a3d net: dsa: don't allocate the slave_mii_bus using devres
The Linux device model permits both the ->shutdown and ->remove driver
methods to get called during a shutdown procedure. Example: a DSA switch
which sits on an SPI bus, and the SPI bus driver calls this on its
->shutdown method:

spi_unregister_controller
-> device_for_each_child(&ctlr->dev, NULL, __unregister);
   -> spi_unregister_device(to_spi_device(dev));
      -> device_del(&spi->dev);

So this is a simple pattern which can theoretically appear on any bus,
although the only other buses on which I've been able to find it are
I2C:

i2c_del_adapter
-> device_for_each_child(&adap->dev, NULL, __unregister_client);
   -> i2c_unregister_device(client);
      -> device_unregister(&client->dev);

The implication of this pattern is that devices on these buses can be
unregistered after having been shut down. The drivers for these devices
might choose to return early either from ->remove or ->shutdown if the
other callback has already run once, and they might choose that the
->shutdown method should only perform a subset of the teardown done by
->remove (to avoid unnecessary delays when rebooting).

So in other words, the device driver may choose on ->remove to not
do anything (therefore to not unregister an MDIO bus it has registered
on ->probe), because this ->remove is actually triggered by the
device_shutdown path, and its ->shutdown method has already run and done
the minimally required cleanup.

This used to be fine until the blamed commit, but now, the following
BUG_ON triggers:

void mdiobus_free(struct mii_bus *bus)
{
	/* For compatibility with error handling in drivers. */
	if (bus->state == MDIOBUS_ALLOCATED) {
		kfree(bus);
		return;
	}

	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
	bus->state = MDIOBUS_RELEASED;

	put_device(&bus->dev);
}

In other words, there is an attempt to free an MDIO bus which was not
unregistered. The attempt to free it comes from the devres release
callbacks of the SPI device, which are executed after the device is
unregistered.

I'm not saying that the fact that MDIO buses allocated using devres
would automatically get unregistered wasn't strange. I'm just saying
that the commit didn't care about auditing existing call paths in the
kernel, and now, the following code sequences are potentially buggy:

(a) devm_mdiobus_alloc followed by plain mdiobus_register, for a device
    located on a bus that unregisters its children on shutdown. After
    the blamed patch, either both the alloc and the register should use
    devres, or none should.

(b) devm_mdiobus_alloc followed by plain mdiobus_register, and then no
    mdiobus_unregister at all in the remove path. After the blamed
    patch, nobody unregisters the MDIO bus anymore, so this is even more
    buggy than the previous case which needs a specific bus
    configuration to be seen, this one is an unconditional bug.

In this case, DSA falls into category (a), it tries to be helpful and
registers an MDIO bus on behalf of the switch, which might be on such a
bus. I've no idea why it does it under devres.

It does this on probe:

	if (!ds->slave_mii_bus && ds->ops->phy_read)
		alloc and register mdio bus

and this on remove:

	if (ds->slave_mii_bus && ds->ops->phy_read)
		unregister mdio bus

I _could_ imagine using devres because the condition used on remove is
different than the condition used on probe. So strictly speaking, DSA
cannot determine whether the ds->slave_mii_bus it sees on remove is the
ds->slave_mii_bus that _it_ has allocated on probe. Using devres would
have solved that problem. But nonetheless, the existing code already
proceeds to unregister the MDIO bus, even though it might be
unregistering an MDIO bus it has never registered. So I can only guess
that no driver that implements ds->ops->phy_read also allocates and
registers ds->slave_mii_bus itself.

So in that case, if unregistering is fine, freeing must be fine too.

Stop using devres and free the MDIO bus manually. This will make devres
stop attempting to free a still registered MDIO bus on ->shutdown.

Fixes: ac3a68d566 ("net: phy: don't abuse devres in devm_mdiobus_register()")
Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-21 13:52:16 +01:00
Vladimir Oltean
e5845aa0ea net: dsa: fix dsa_tree_setup error path
Since the blamed commit, dsa_tree_teardown_switches() was split into two
smaller functions, dsa_tree_teardown_switches and dsa_tree_teardown_ports.

However, the error path of dsa_tree_setup stopped calling dsa_tree_teardown_ports.

Fixes: a57d8c217a ("net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-21 10:59:39 +01:00
Karsten Graul
a18cee4791 net/smc: fix 'workqueue leaked lock' in smc_conn_abort_work
The abort_work is scheduled when a connection was detected to be
out-of-sync after a link failure. The work calls smc_conn_kill(),
which calls smc_close_active_abort() and that might end up calling
smc_close_cancel_work().
smc_close_cancel_work() cancels any pending close_work and tx_work but
needs to release the sock_lock before and acquires the sock_lock again
afterwards. So when the sock_lock was NOT acquired before then it may
be held after the abort_work completes. Thats why the sock_lock is
acquired before the call to smc_conn_kill() in __smc_lgr_terminate(),
but this is missing in smc_conn_abort_work().

Fix that by acquiring the sock_lock first and release it after the
call to smc_conn_kill().

Fixes: b286a0651e ("net/smc: handle incoming CDC validation message")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-21 10:54:16 +01:00
Karsten Graul
6c90731980 net/smc: add missing error check in smc_clc_prfx_set()
Coverity stumbled over a missing error check in smc_clc_prfx_set():

*** CID 1475954:  Error handling issues  (CHECKED_RETURN)
/net/smc/smc_clc.c: 233 in smc_clc_prfx_set()
>>>     CID 1475954:  Error handling issues  (CHECKED_RETURN)
>>>     Calling "kernel_getsockname" without checking return value (as is done elsewhere 8 out of 10 times).
233     	kernel_getsockname(clcsock, (struct sockaddr *)&addrs);

Add the return code check in smc_clc_prfx_set().

Fixes: c246d942ea ("net/smc: restructure netinfo for CLC proposal msgs")
Reported-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-21 10:54:16 +01:00
Eric Dumazet
e9edc188fc netfilter: conntrack: serialize hash resizes and cleanups
Syzbot was able to trigger the following warning [1]

No repro found by syzbot yet but I was able to trigger similar issue
by having 2 scripts running in parallel, changing conntrack hash sizes,
and:

for j in `seq 1 1000` ; do unshare -n /bin/true >/dev/null ; done

It would take more than 5 minutes for net_namespace structures
to be cleaned up.

This is because nf_ct_iterate_cleanup() has to restart everytime
a resize happened.

By adding a mutex, we can serialize hash resizes and cleanups
and also make get_next_corpse() faster by skipping over empty
buckets.

Even without resizes in the picture, this patch considerably
speeds up network namespace dismantles.

[1]
INFO: task syz-executor.0:8312 can't die for more than 144 seconds.
task:syz-executor.0  state:R  running task     stack:25672 pid: 8312 ppid:  6573 flags:0x00004006
Call Trace:
 context_switch kernel/sched/core.c:4955 [inline]
 __schedule+0x940/0x26f0 kernel/sched/core.c:6236
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6408
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
 __local_bh_enable_ip+0x109/0x120 kernel/softirq.c:390
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:2252 [inline]
 nf_ct_iterate_cleanup+0x15a/0x450 net/netfilter/nf_conntrack_core.c:2275
 nf_conntrack_cleanup_net_list+0x14c/0x4f0 net/netfilter/nf_conntrack_core.c:2469
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 setup_net+0x639/0xa30 net/core/net_namespace.c:349
 copy_net_ns+0x319/0x760 net/core/net_namespace.c:470
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3128
 __do_sys_unshare kernel/fork.c:3202 [inline]
 __se_sys_unshare kernel/fork.c:3200 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3200
 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: 0033:0x7f63da68e739
RSP: 002b:00007f63d7c05188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f63da792f80 RCX: 00007f63da68e739
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f63da6e8cc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63da792f80
R13: 00007fff50b75d3f R14: 00007f63d7c05300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8b980020 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
2 locks held by kworker/u4:2/153:
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc9000140fdb0 ((kfence_timer).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
1 lock held by systemd-udevd/2970:
1 lock held by in:imklog/6258:
 #0: ffff88807f970ff0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
3 locks held by kworker/1:6/8158:
1 lock held by syz-executor.0/8312:
2 locks held by kworker/u4:13/9320:
1 lock held by syz-executor.5/10178:
1 lock held by syz-executor.4/10217:

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:56 +02:00
Florian Westphal
b53deef054 netfilter: log: work around missing softdep backend module
iptables/nftables has two types of log modules:

1. backend, e.g. nf_log_syslog, which implement the functionality
2. frontend, e.g. xt_LOG or nft_log, which call the functionality
   provided by backend based on nf_tables or xtables rule set.

Problem is that the request_module() call to load the backed in
nf_logger_find_get() might happen with nftables transaction mutex held
in case the call path is via nf_tables/nft_compat.

This can cause deadlocks (see 'Fixes' tags for details).

The chosen solution as to let modprobe deal with this by adding 'pre: '
soft dep tag to xt_LOG (to load the syslog backend) and xt_NFLOG (to
load nflog backend).

Eric reports that this breaks on systems with older modprobe that
doesn't support softdeps.

Another, similar issue occurs when someone either insmods xt_(NF)LOG
directly or unloads the backend module (possible if no log frontend
is in use): because the frontend module is already loaded, modprobe is
not invoked again so the softdep isn't evaluated.

Add a workaround: If nf_logger_find_get() returns -ENOENT and call
is not via nft_compat, load the backend explicitly and try again.

Else, let nft_compat ask for deferred request_module via nf_tables
infra.

Softdeps are kept in-place, so with newer modprobe the dependencies
are resolved from userspace.

Fixes: cefa31a9d4 ("netfilter: nft_log: perform module load from nf_tables")
Fixes: a38b5b56d6 ("netfilter: nf_log: add module softdeps")
Reported-and-tested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:56 +02:00
Florian Westphal
cc8072153a netfilter: iptable_raw: drop bogus net_init annotation
This is a leftover from the times when this function was wired up via
pernet_operations.  Now its called when userspace asks for the table.

With CONFIG_NET_NS=n, iptable_raw_table_init memory has been discarded
already and we get a kernel crash.

Other tables are fine, __net_init annotation was removed already.

Fixes: fdacd57c79 ("netfilter: x_tables: never register tables by default")
Reported-by: youling 257 <youling257@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:56 +02:00
Florian Westphal
7970a19b71 netfilter: nf_nat_masquerade: defer conntrack walk to work queue
The ipv4 and device notifiers are called with RTNL mutex held.
The table walk can take some time, better not block other RTNL users.

'ip a' has been reported to block for up to 20 seconds when conntrack table
has many entries and device down events are frequent (e.g., PPP).

Reported-and-tested-by: Martin Zaharinov <micron10@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:56 +02:00
Florian Westphal
30db406923 netfilter: nf_nat_masquerade: make async masq_inet6_event handling generic
masq_inet6_event is called asynchronously from system work queue,
because the inet6 notifier is atomic and nf_iterate_cleanup can sleep.

The ipv4 and device notifiers call nf_iterate_cleanup directly.

This is legal, but these notifiers are called with RTNL mutex held.
A large conntrack table with many devices coming and going will have severe
impact on the system usability, with 'ip a' blocking for several seconds.

This change places the defer code into a helper and makes it more
generic so ipv4 and ifdown notifiers can be converted to defer the
cleanup walk as well in a follow patch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:56 +02:00
Pablo Neira Ayuso
45928afe94 netfilter: nf_tables: Fix oversized kvmalloc() calls
The commit 7661809d49 ("mm: don't allow oversized kvmalloc() calls")
limits the max allocatable memory via kvmalloc() to MAX_INT.

Reported-by: syzbot+cd43695a64bcd21b8596@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:55 +02:00
Florian Westphal
a499b03bf3 netfilter: nf_tables: unlink table before deleting it
syzbot reports following UAF:
BUG: KASAN: use-after-free in memcmp+0x18f/0x1c0 lib/string.c:955
 nla_strcmp+0xf2/0x130 lib/nlattr.c:836
 nft_table_lookup.part.0+0x1a2/0x460 net/netfilter/nf_tables_api.c:570
 nft_table_lookup net/netfilter/nf_tables_api.c:4064 [inline]
 nf_tables_getset+0x1b3/0x860 net/netfilter/nf_tables_api.c:4064
 nfnetlink_rcv_msg+0x659/0x13f0 net/netfilter/nfnetlink.c:285
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504

Problem is that all get operations are lockless, so the commit_mutex
held by nft_rcv_nl_event() isn't enough to stop a parallel GET request
from doing read-accesses to the table object even after synchronize_rcu().

To avoid this, unlink the table first and store the table objects in
on-stack scratch space.

Fixes: 6001a930ce ("netfilter: nftables: introduce table ownership")
Reported-and-tested-by: syzbot+f31660cf279b0557160c@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:55 +02:00
Florian Westphal
d2966dc77b netfilter: nat: include zone id in nat table hash again
Similar to the conntrack change, also use the zone id for the nat source
lists if the zone id is valid in both directions.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:55 +02:00
Florian Westphal
b16ac3c4c8 netfilter: conntrack: include zone id in tuple hash again
commit deedb59039 ("netfilter: nf_conntrack: add direction support for zones")
removed the zone id from the hash value.

This has implications on hash chain lengths with overlapping tuples, which
can hit 64k entries on released kernels, before upper droplimit was added
in d7e7747ac5 ("netfilter: refuse insertion if chain has grown too large").

With that change reverted, test script coming with this series shows
linear insertion time growth:

 10000 entries in 3737 ms (now 10000 total, loop 1)
 10000 entries in 16994 ms (now 20000 total, loop 2)
 10000 entries in 47787 ms (now 30000 total, loop 3)
 10000 entries in 72731 ms (now 40000 total, loop 4)
 10000 entries in 95761 ms (now 50000 total, loop 5)
 10000 entries in 96809 ms (now 60000 total, loop 6)
 inserted 60000 entries from packet path in 333825 ms

With d7e7747ac5 in place, the test fails.

There are three supported zone use cases:
 1. Connection is in the default zone (zone 0).
    This means to special config (the default).
 2. Connection is in a different zone (1 to 2**16).
    This means rules are in place to put packets in
    the desired zone, e.g. derived from vlan id or interface.
 3. Original direction is in zone X and Reply is in zone 0.

3) allows to use of the existing NAT port collision avoidance to provide
   connectivity to internet/wan even when the various zones have overlapping
   source networks separated via policy routing.

In case the original zone is 0 all three cases are identical.

There is no way to place original direction in zone x and reply in
zone y (with y != 0).

Zones need to be assigned manually via the iptables/nftables ruleset,
before conntrack lookup occurs (raw table in iptables) using the
"CT" target conntrack template support
(-j CT --{zone,zone-orig,zone-reply} X).

Normally zone assignment happens based on incoming interface, but could
also be derived from packet mark, vlan id and so on.

This means that when case 3 is used, the ruleset will typically not even
assign a connection tracking template to the "reply" packets, so lookup
happens in zone 0.

However, it is possible that reply packets also match a ct zone
assignment rule which sets up a template for zone X (X > 0) in original
direction only.

Therefore, after making the zone id part of the hash, we need to do a
second lookup using the reply zone id if we did not find an entry on
the first lookup.

In practice, most deployments will either not use zones at all or the
origin and reply zones are the same, no second lookup is required in
either case.

After this change, packet path insertion test passes with constant
insertion times:

 10000 entries in 1064 ms (now 10000 total, loop 1)
 10000 entries in 1074 ms (now 20000 total, loop 2)
 10000 entries in 1066 ms (now 30000 total, loop 3)
 10000 entries in 1079 ms (now 40000 total, loop 4)
 10000 entries in 1081 ms (now 50000 total, loop 5)
 10000 entries in 1082 ms (now 60000 total, loop 6)
 inserted 60000 entries from packet path in 6452 ms

Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:55 +02:00
Florian Westphal
c9c3b6811f netfilter: conntrack: make max chain length random
Similar to commit 67d6d681e1
("ipv4: make exception cache less predictible"):

Use a random drop length to make it harder to detect when entries were
hashed to same bucket list.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-21 03:46:55 +02:00
Ido Schimmel
563f23b002 nexthop: Fix division by zero while replacing a resilient group
The resilient nexthop group torture tests in fib_nexthop.sh exposed a
possible division by zero while replacing a resilient group [1]. The
division by zero occurs when the data path sees a resilient nexthop
group with zero buckets.

The tests replace a resilient nexthop group in a loop while traffic is
forwarded through it. The tests do not specify the number of buckets
while performing the replacement, resulting in the kernel allocating a
stub resilient table (i.e, 'struct nh_res_table') with zero buckets.

This table should never be visible to the data path, but the old nexthop
group (i.e., 'oldg') might still be used by the data path when the stub
table is assigned to it.

Fix this by only assigning the stub table to the old nexthop group after
making sure the group is no longer used by the data path.

Tested with fib_nexthops.sh:

Tests passed: 222
Tests failed:   0

[1]
 divide error: 0000 [#1] PREEMPT SMP KASAN
 CPU: 0 PID: 1850 Comm: ping Not tainted 5.14.0-custom-10271-ga86eb53057fe #1107
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014
 RIP: 0010:nexthop_select_path+0x2d2/0x1a80
[...]
 Call Trace:
  fib_select_multipath+0x79b/0x1530
  fib_select_path+0x8fb/0x1c10
  ip_route_output_key_hash_rcu+0x1198/0x2da0
  ip_route_output_key_hash+0x190/0x340
  ip_route_output_flow+0x21/0x120
  raw_sendmsg+0x91d/0x2e10
  inet_sendmsg+0x9e/0xe0
  __sys_sendto+0x23d/0x360
  __x64_sys_sendto+0xe1/0x1b0
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae

Cc: stable@vger.kernel.org
Fixes: 283a72a559 ("nexthop: Add implementation of resilient next-hop groups")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-20 09:45:14 +01:00
Xuan Zhuo
3765996e4f napi: fix race inside napi_enable
The process will cause napi.state to contain NAPI_STATE_SCHED and
not in the poll_list, which will cause napi_disable() to get stuck.

The prefix "NAPI_STATE_" is removed in the figure below, and
NAPI_STATE_HASHED is ignored in napi.state.

                      CPU0       |                   CPU1       | napi.state
===============================================================================
napi_disable()                   |                              | SCHED | NPSVC
napi_enable()                    |                              |
{                                |                              |
    smp_mb__before_atomic();     |                              |
    clear_bit(SCHED, &n->state); |                              | NPSVC
                                 | napi_schedule_prep()         | SCHED | NPSVC
                                 | napi_poll()                  |
                                 |   napi_complete_done()       |
                                 |   {                          |
                                 |      if (n->state & (NPSVC | | (1)
                                 |               _BUSY_POLL)))  |
                                 |           return false;      |
                                 |     ................         |
                                 |   }                          | SCHED | NPSVC
                                 |                              |
    clear_bit(NPSVC, &n->state); |                              | SCHED
}                                |                              |
                                 |                              |
napi_schedule_prep()             |                              | SCHED | MISSED (2)

(1) Here return direct. Because of NAPI_STATE_NPSVC exists.
(2) NAPI_STATE_SCHED exists. So not add napi.poll_list to sd->poll_list

Since NAPI_STATE_SCHED already exists and napi is not in the
sd->poll_list queue, NAPI_STATE_SCHED cannot be cleared and will always
exist.

1. This will cause this queue to no longer receive packets.
2. If you encounter napi_disable under the protection of rtnl_lock, it
   will cause the entire rtnl_lock to be locked, affecting the overall
   system.

This patch uses cmpxchg to implement napi_enable(), which ensures that
there will be no race due to the separation of clear two bits.

Fixes: 2d8bff1269 ("netpoll: Close race condition between poll_one_napi and napi_disable")
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-20 09:41:29 +01:00
Vladimir Oltean
fd292c189a net: dsa: tear down devlink port regions when tearing down the devlink port on error
Commit 86f8b1c01a ("net: dsa: Do not make user port errors fatal")
decided it was fine to ignore errors on certain ports that fail to
probe, and go on with the ports that do probe fine.

Commit fb6ec87f72 ("net: dsa: Fix type was not set for devlink port")
noticed that devlink_port_type_eth_set(dlp, dp->slave); does not get
called, and devlink notices after a timeout of 3600 seconds and prints a
WARN_ON. So it went ahead to unregister the devlink port. And because
there exists an UNUSED port flavour, we actually re-register the devlink
port as UNUSED.

Commit 08156ba430 ("net: dsa: Add devlink port regions support to
DSA") added devlink port regions, which are set up by the driver and not
by DSA.

When we trigger the devlink port deregistration and reregistration as
unused, devlink now prints another WARN_ON, from here:

devlink_port_unregister:
	WARN_ON(!list_empty(&devlink_port->region_list));

So the port still has regions, which makes sense, because they were set
up by the driver, and the driver doesn't know we're unregistering the
devlink port.

Somebody needs to tear them down, and optionally (actually it would be
nice, to be consistent) set them up again for the new devlink port.

But DSA's layering stays in our way quite badly here.

The options I've considered are:

1. Introduce a function in devlink to just change a port's type and
   flavour. No dice, devlink keeps a lot of state, it really wants the
   port to not be registered when you set its parameters, so changing
   anything can only be done by destroying what we currently have and
   recreating it.

2. Make DSA cache the parameters passed to dsa_devlink_port_region_create,
   and the region returned, keep those in a list, then when the devlink
   port unregister needs to take place, the existing devlink regions are
   destroyed by DSA, and we replay the creation of new regions using the
   cached parameters. Problem: mv88e6xxx keeps the region pointers in
   chip->ports[port].region, and these will remain stale after DSA frees
   them. There are many things DSA can do, but updating mv88e6xxx's
   private pointers is not one of them.

3. Just let the driver do it (i.e. introduce a very specific method
   called ds->ops->port_reinit_as_unused, which unregisters its devlink
   port devlink regions, then the old devlink port, then registers the
   new one, then the devlink port regions for it). While it does work,
   as opposed to the others, it's pretty horrible from an API
   perspective and we can do better.

4. Introduce a new pair of methods, ->port_setup and ->port_teardown,
   which in the case of mv88e6xxx must register and unregister the
   devlink port regions. Call these 2 methods when the port must be
   reinitialized as unused.

Naturally, I went for the 4th approach.

Fixes: 08156ba430 ("net: dsa: Add devlink port regions support to DSA")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 13:05:44 +01:00
Thomas Gleixner
2dcb96bacc net: core: Correct the sock::sk_lock.owned lockdep annotations
lock_sock_fast() and lock_sock_nested() contain lockdep annotations for the
sock::sk_lock.owned 'mutex'. sock::sk_lock.owned is not a regular mutex. It
is just lockdep wise equivalent. In fact it's an open coded trivial mutex
implementation with some interesting features.

sock::sk_lock.slock is a regular spinlock protecting the 'mutex'
representation sock::sk_lock.owned which is a plain boolean. If 'owned' is
true, then some other task holds the 'mutex', otherwise it is uncontended.
As this locking construct is obviously endangered by lock ordering issues as
any other locking primitive it got lockdep annotated via a dedicated
dependency map sock::sk_lock.dep_map which has to be updated at the lock
and unlock sites.

lock_sock_nested() is a straight forward 'mutex' lock operation:

  might_sleep();
  spin_lock_bh(sock::sk_lock.slock)
  while (!try_lock(sock::sk_lock.owned)) {
      spin_unlock_bh(sock::sk_lock.slock);
      wait_for_release();
      spin_lock_bh(sock::sk_lock.slock);
  }

The lockdep annotation for sock::sk_lock.owned is for unknown reasons
_after_ the lock has been acquired, i.e. after the code block above and
after releasing sock::sk_lock.slock, but inside the bottom halves disabled
region:

  spin_unlock(sock::sk_lock.slock);
  mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
  local_bh_enable();

The placement after the unlock is obvious because otherwise the
mutex_acquire() would nest into the spin lock held region.

But that's from the lockdep perspective still the wrong place:

 1) The mutex_acquire() is issued _after_ the successful acquisition which
    is pointless because in a dead lock scenario this point is never
    reached which means that if the deadlock is the first instance of
    exposing the wrong lock order lockdep does not have a chance to detect
    it.

 2) It only works because lockdep is rather lax on the context from which
    the mutex_acquire() is issued. Acquiring a mutex inside a bottom halves
    and therefore non-preemptible region is obviously invalid, except for a
    trylock which is clearly not the case here.

    This 'works' stops working on RT enabled kernels where the bottom halves
    serialization is done via a local lock, which exposes this misplacement
    because the 'mutex' and the local lock nest the wrong way around and
    lockdep complains rightfully about a lock inversion.

The placement is wrong since the initial commit a5b5bb9a05 ("[PATCH]
lockdep: annotate sk_locks") which introduced this.

Fix it by moving the mutex_acquire() in front of the actual lock
acquisition, which is what the regular mutex_lock() operation does as well.

lock_sock_fast() is not that straight forward. It looks at the first glance
like a convoluted trylock operation:

  spin_lock_bh(sock::sk_lock.slock)
  if (!sock::sk_lock.owned)
      return false;
  while (!try_lock(sock::sk_lock.owned)) {
      spin_unlock_bh(sock::sk_lock.slock);
      wait_for_release();
      spin_lock_bh(sock::sk_lock.slock);
  }
  spin_unlock(sock::sk_lock.slock);
  mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
  local_bh_enable();
  return true;

But that's not the case: lock_sock_fast() is an interesting optimization
for short critical sections which can run with bottom halves disabled and
sock::sk_lock.slock held. This allows to shortcut the 'mutex' operation in
the non contended case by preventing other lockers to acquire
sock::sk_lock.owned because they are blocked on sock::sk_lock.slock, which
in turn avoids the overhead of doing the heavy processing in release_sock()
including waking up wait queue waiters.

In the contended case, i.e. when sock::sk_lock.owned == true the behavior
is the same as lock_sock_nested().

Semantically this shortcut means, that the task acquired the 'mutex' even
if it does not touch the sock::sk_lock.owned field in the non-contended
case. Not telling lockdep about this shortcut acquisition is hiding
potential lock ordering violations in the fast path.

As a consequence the same reasoning as for the above lock_sock_nested()
case vs. the placement of the lockdep annotation applies.

The current placement of the lockdep annotation was just copied from
the original lock_sock(), now renamed to lock_sock_nested(),
implementation.

Fix this by moving the mutex_acquire() in front of the actual lock
acquisition and adding the corresponding mutex_release() into
unlock_sock_fast(). Also document the fast path return case with a comment.

Reported-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 12:48:06 +01:00
Vladimir Oltean
0650bf52b3 net: dsa: be compatible with masters which unregister on shutdown
Lino reports that on his system with bcmgenet as DSA master and KSZ9897
as a switch, rebooting or shutting down never works properly.

What does the bcmgenet driver have special to trigger this, that other
DSA masters do not? It has an implementation of ->shutdown which simply
calls its ->remove implementation. Otherwise said, it unregisters its
network interface on shutdown.

This message can be seen in a loop, and it hangs the reboot process there:

unregister_netdevice: waiting for eth0 to become free. Usage count = 3

So why 3?

A usage count of 1 is normal for a registered network interface, and any
virtual interface which links itself as an upper of that will increment
it via dev_hold. In the case of DSA, this is the call path:

dsa_slave_create
-> netdev_upper_dev_link
   -> __netdev_upper_dev_link
      -> __netdev_adjacent_dev_insert
         -> dev_hold

So a DSA switch with 3 interfaces will result in a usage count elevated
by two, and netdev_wait_allrefs will wait until they have gone away.

Other stacked interfaces, like VLAN, watch NETDEV_UNREGISTER events and
delete themselves, but DSA cannot just vanish and go poof, at most it
can unbind itself from the switch devices, but that must happen strictly
earlier compared to when the DSA master unregisters its net_device, so
reacting on the NETDEV_UNREGISTER event is way too late.

It seems that it is a pretty established pattern to have a driver's
->shutdown hook redirect to its ->remove hook, so the same code is
executed regardless of whether the driver is unbound from the device, or
the system is just shutting down. As Florian puts it, it is quite a big
hammer for bcmgenet to unregister its net_device during shutdown, but
having a common code path with the driver unbind helps ensure it is well
tested.

So DSA, for better or for worse, has to live with that and engage in an
arms race of implementing the ->shutdown hook too, from all individual
drivers, and do something sane when paired with masters that unregister
their net_device there. The only sane thing to do, of course, is to
unlink from the master.

However, complications arise really quickly.

The pattern of redirecting ->shutdown to ->remove is not unique to
bcmgenet or even to net_device drivers. In fact, SPI controllers do it
too (see dspi_shutdown -> dspi_remove), and presumably, I2C controllers
and MDIO controllers do it too (this is something I have not researched
too deeply, but even if this is not the case today, it is certainly
plausible to happen in the future, and must be taken into consideration).

Since DSA switches might be SPI devices, I2C devices, MDIO devices, the
insane implication is that for the exact same DSA switch device, we
might have both ->shutdown and ->remove getting called.

So we need to do something with that insane environment. The pattern
I've come up with is "if this, then not that", so if either ->shutdown
or ->remove gets called, we set the device's drvdata to NULL, and in the
other hook, we check whether the drvdata is NULL and just do nothing.
This is probably not necessary for platform devices, just for devices on
buses, but I would really insist for consistency among drivers, because
when code is copy-pasted, it is not always copy-pasted from the best
sources.

So depending on whether the DSA switch's ->remove or ->shutdown will get
called first, we cannot really guarantee even for the same driver if
rebooting will result in the same code path on all platforms. But
nonetheless, we need to do something minimally reasonable on ->shutdown
too to fix the bug. Of course, the ->remove will do more (a full
teardown of the tree, with all data structures freed, and this is why
the bug was not caught for so long). The new ->shutdown method is kept
separate from dsa_unregister_switch not because we couldn't have
unregistered the switch, but simply in the interest of doing something
quick and to the point.

The big question is: does the DSA switch's ->shutdown get called earlier
than the DSA master's ->shutdown? If not, there is still a risk that we
might still trigger the WARN_ON in unregister_netdevice that says we are
attempting to unregister a net_device which has uppers. That's no good.
Although the reference to the master net_device won't physically go away
even if DSA's ->shutdown comes afterwards, remember we have a dev_hold
on it.

The answer to that question lies in this comment above device_link_add:

 * A side effect of the link creation is re-ordering of dpm_list and the
 * devices_kset list by moving the consumer device and all devices depending
 * on it to the ends of these lists (that does not happen to devices that have
 * not been registered when this function is called).

so the fact that DSA uses device_link_add towards its master is not
exactly for nothing. device_shutdown() walks devices_kset from the back,
so this is our guarantee that DSA's shutdown happens before the master's
shutdown.

Fixes: 2f1e8ea726 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings")
Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/
Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 12:08:37 +01:00
Vladimir Oltean
3c9cfb5269 net: update NXP copyright text
NXP Legal insists that the following are not fine:

- Saying "NXP Semiconductors" instead of "NXP", since the company's
  registered name is "NXP"

- Putting a "(c)" sign in the copyright string

- Putting a comma in the copyright string

The only accepted copyright string format is "Copyright <year-range> NXP".

This patch changes the copyright headers in the networking files that
were sent by me, or derived from code sent by me.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-17 13:52:17 +01:00