Some transports (hyperv, virtio) acquire the sock lock during the
.release() callback.

In the vsock_stream_connect() we call vsock_assign_transport(); if
the socket was previously assigned to another transport, the
vsk->transport->release() is called, but the sock lock is already
held in the vsock_stream_connect(), causing a deadlock reported by
syzbot:

    INFO: task syz-executor280:9768 blocked for more than 143 seconds.
      Not tainted 5.6.0-rc1-syzkaller #0
    "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
    syz-executor280 D27912  9768   9766 0x00000000
    Call Trace:
     context_switch kernel/sched/core.c:3386 [inline]
     __schedule+0x934/0x1f90 kernel/sched/core.c:4082
     schedule+0xdc/0x2b0 kernel/sched/core.c:4156
     __lock_sock+0x165/0x290 net/core/sock.c:2413
     lock_sock_nested+0xfe/0x120 net/core/sock.c:2938
     virtio_transport_release+0xc4/0xd60 net/vmw_vsock/virtio_transport_common.c:832
     vsock_assign_transport+0xf3/0x3b0 net/vmw_vsock/af_vsock.c:454
     vsock_stream_connect+0x2b3/0xc70 net/vmw_vsock/af_vsock.c:1288
     __sys_connect_file+0x161/0x1c0 net/socket.c:1857
     __sys_connect+0x174/0x1b0 net/socket.c:1874
     __do_sys_connect net/socket.c:1885 [inline]
     __se_sys_connect net/socket.c:1882 [inline]
     __x64_sys_connect+0x73/0xb0 net/socket.c:1882
     do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
     entry_SYSCALL_64_after_hwframe+0x49/0xbe

To avoid this issue, this patch remove the lock acquiring in the
.release() callback of hyperv and virtio transports, and it holds
the lock when we call vsk->transport->release() in the vsock core.

Reported-by:  <syzbot+731710996d79d0d58fbc@syzkaller.appspotmail.com>
Fixes: 408624af ("vsock: use local transport when it is loaded")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes: 3a12500e ("unix: define and set show_fdinfo only if procfs is enabled")
Signed-off-by: David S. Miller <davem@davemloft.net>

Follow the pattern used with other *_show_fdinfo functions and only
define unix_show_fdinfo and set it in proto_ops if CONFIG_PROCFS
is set.

Fixes: 3c32da19 ("unix: Show number of pending scm files of receive queue in fdinfo")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In smc_ib_remove_dev() check if the provided ib device was actually
initialized for SMC before.

Reported-by:  <syzbot+84484ccebdd4e5451d91@syzkaller.appspotmail.com>
Fixes: a4cf0443 ("smc: introduce SMC as an IB-client")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot noted that the master MPTCP socket lacks the icsk_sync_mss
callback, and was able to trigger a null pointer dereference:

BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 8e171067 P4D 8e171067 PUD 93fa2067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8984 Comm: syz-executor066 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffffc900020b7b80 EFLAGS: 00010246
RAX: 1ffff110124ba600 RBX: 0000000000000000 RCX: ffff88809fefa600
RDX: ffff8880994cdb18 RSI: 0000000000000000 RDI: ffff8880925d3140
RBP: ffffc900020b7bd8 R08: ffffffff870225be R09: fffffbfff140652a
R10: fffffbfff140652a R11: 0000000000000000 R12: ffff8880925d35d0
R13: ffff8880925d3140 R14: dffffc0000000000 R15: 1ffff110124ba6ba
FS:  0000000001a0b880(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000a6d6f000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 cipso_v4_sock_setattr+0x34b/0x470 net/ipv4/cipso_ipv4.c:1888
 netlbl_sock_setattr+0x2a7/0x310 net/netlabel/netlabel_kapi.c:989
 smack_netlabel security/smack/smack_lsm.c:2425 [inline]
 smack_inode_setsecurity+0x3da/0x4a0 security/smack/smack_lsm.c:2716
 security_inode_setsecurity+0xb2/0x140 security/security.c:1364
 __vfs_setxattr_noperm+0x16f/0x3e0 fs/xattr.c:197
 vfs_setxattr fs/xattr.c:224 [inline]
 setxattr+0x335/0x430 fs/xattr.c:451
 __do_sys_fsetxattr fs/xattr.c:506 [inline]
 __se_sys_fsetxattr+0x130/0x1b0 fs/xattr.c:495
 __x64_sys_fsetxattr+0xbf/0xd0 fs/xattr.c:495
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440199
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffcadc19e48 EFLAGS: 00000246 ORIG_RAX: 00000000000000be
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440199
RDX: 0000000020000200 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000003 R09: 00000000004002c8
R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000401a20
R13: 0000000000401ab0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
CR2: 0000000000000000

Address the issue adding a dummy icsk_sync_mss callback.
To properly sync the subflows mss and options list we need some
additional infrastructure, which will land to net-next.

Reported-by:  <syzbot+f4dfece964792d80b139@syzkaller.appspotmail.com>
Fixes: 2303f994 ("mptcp: Associate MPTCP context with TCP socket")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

IPV6_ADDRFORM is able to transform IPv6 socket to IPv4 one.
While this operation sounds illogical, we have to support it.

One of the things it does for TCP socket is to switch sk->sk_prot
to tcp_prot.

We now have other layers playing with sk->sk_prot, so we should make
sure to not interfere with them.

This patch makes sure sk_prot is the default pointer for TCP IPv6 socket.

syzbot reported :
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD a0113067 P4D a0113067 PUD a8771067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10686 Comm: syz-executor.0 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffffc9000281fce0 EFLAGS: 00010246
RAX: 1ffffffff15f48ac RBX: ffffffff8afa4560 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a69a8f40
RBP: ffffc9000281fd10 R08: ffffffff86ed9b0c R09: ffffed1014d351f5
R10: ffffed1014d351f5 R11: 0000000000000000 R12: ffff8880920d3098
R13: 1ffff1101241a613 R14: ffff8880a69a8f40 R15: 0000000000000000
FS:  00007f2ae75db700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000a3b85000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 inet_release+0x165/0x1c0 net/ipv4/af_inet.c:427
 __sock_release net/socket.c:605 [inline]
 sock_close+0xe1/0x260 net/socket.c:1283
 __fput+0x2e4/0x740 fs/file_table.c:280
 ____fput+0x15/0x20 fs/file_table.c:313
 task_work_run+0x176/0x1b0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:164 [inline]
 prepare_exit_to_usermode+0x480/0x5b0 arch/x86/entry/common.c:195
 syscall_return_slowpath+0x113/0x4a0 arch/x86/entry/common.c:278
 do_syscall_64+0x11f/0x1c0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c429
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2ae75dac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: 0000000000000000 RBX: 00007f2ae75db6d4 RCX: 000000000045c429
RDX: 0000000000000001 RSI: 000000000000011a RDI: 0000000000000004
RBP: 000000000076bf20 R08: 0000000000000038 R09: 0000000000000000
R10: 0000000020000180 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a9d R14: 00000000004ccfb4 R15: 000000000076bf2c
Modules linked in:
CR2: 0000000000000000
---[ end trace 82567b5207e87bae ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffffc9000281fce0 EFLAGS: 00010246
RAX: 1ffffffff15f48ac RBX: ffffffff8afa4560 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a69a8f40
RBP: ffffc9000281fd10 R08: ffffffff86ed9b0c R09: ffffed1014d351f5
R10: ffffed1014d351f5 R11: 0000000000000000 R12: ffff8880920d3098
R13: 1ffff1101241a613 R14: ffff8880a69a8f40 R15: 0000000000000000
FS:  00007f2ae75db700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000a3b85000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 604326b4 ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by:  <syzbot+1938db17e275e85dc328@syzkaller.appspotmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

If an SMC connection to a certain peer is setup the first time,
a new linkgroup is created. In case of setup failures, such a
linkgroup is unusable and should disappear. As a first step the
linkgroup is removed from the linkgroup list in smc_lgr_forget().

There are 2 problems:
smc_listen_decline() might be called before linkgroup creation
resulting in a crash due to calling smc_lgr_forget() with
parameter NULL.
If a setup failure occurs after linkgroup creation, the connection
is never unregistered from the linkgroup, preventing linkgroup
freeing.

This patch introduces an enhanced smc_lgr_cleanup_early() function
which
* contains a linkgroup check for early smc_listen_decline()
  invocations
* invokes smc_conn_free() to guarantee unregistering of the
  connection.
* schedules fast linkgroup removal of the unusable linkgroup

And the unused function smcd_conn_free() is removed from smc_core.h.

Fixes: 3b2dec26 ("net/smc: restructure client and server code in af_smc")
Fixes: 2a0674ff ("net/smc: improve abnormal termination of link groups")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The put of the flags was added by the commit referenced in fixes tag,
however the size of the message was not extended accordingly.

Fix this by adding size of the flags bitfield to the message size.

Fixes: e3822678 ("net: sched: update action implementations to support flags")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled.

The devlink->lock is held when devlink_dpipe_table_find()
is called in non RCU read side section. Therefore, pass struct devlink
to devlink_dpipe_table_find() for lockdep checking.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Before releasing the global mutex, we only unlink the hashtable
from the hash list, its proc file is still not unregistered at
this point. So syzbot could trigger a race condition where a
parallel htable_create() could register the same file immediately
after the mutex is released.

Move htable_remove_proc_entry() back to mutex protection to
fix this. And, fold htable_destroy() into htable_put() to make
the code slightly easier to understand.

Reported-and-tested-by:  <syzbot+d195fd3b9a364ddd6731@syzkaller.appspotmail.com>
Fixes: c4a3922d ("netfilter: xt_hashlimit: reduce hashlimit_mutex scope for htable_put()")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Syzbot reported that ethnl_compact_sanity_checks() can be tricked into
reading past the end of ETHTOOL_A_BITSET_VALUE and ETHTOOL_A_BITSET_MASK
attributes and even the message by passing a value between (u32)(-31)
and (u32)(-1) as ETHTOOL_A_BITSET_SIZE.

The problem is that DIV_ROUND_UP(attr_nbits, 32) is 0 for such values so
that zero length ETHTOOL_A_BITSET_VALUE will pass the length check but
ethnl_bitmap32_not_zero() check would try to access up to 512 MB of
attribute "payload".

Prevent this overflow byt limiting the bitset size. Technically, compact
bitset format would allow bitset sizes up to almost 2^18 (so that the
nest size does not exceed U16_MAX) but bitsets used by ethtool are much
shorter. S16_MAX, the largest value which can be directly used as an
upper limit in policy, should be a reasonable compromise.

Fixes: 10b518d4 ("ethtool: netlink bitset handling")
Reported-by:  <syzbot+7fd4ed5b4234ab1fdccd@syzkaller.appspotmail.com>
Reported-by:  <syzbot+709b7a64d57978247e44@syzkaller.appspotmail.com>
Reported-by:  <syzbot+983cb8fb2d17a7af549d@syzkaller.appspotmail.com>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes the lower and upper bounds when there are multiple TCs and
traffic is on the the same TC on the same device.

The lower bound is represented by 'qoffset' and the upper limit for
hash value is 'qcount + qoffset'. This gives a clean Rx to Tx queue
mapping when there are multiple TCs, as the queue indices for upper TCs
will be offset by 'qoffset'.

v2: Fixed commit description based on comments.

Fixes: 1b837d48 ("net: Revoke export for __skb_tx_hash, update it to just be static skb_tx_hash")
Fixes: eadec877 ("net: Add support for subordinate traffic classes to netdev_pick_tx")
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Phil reports that adding elements, flushing and re-adding them
right away:

  nft add table t '{ set s { type ipv4_addr . inet_service; flags interval; }; }'
  nft add element t s '{ 10.0.0.1 . 22-25, 10.0.0.1 . 10-20 }'
  nft flush set t s
  nft add element t s '{ 10.0.0.1 . 10-20, 10.0.0.1 . 22-25 }'

triggers, almost reliably, a crash like this one:

  [   71.319848] general protection fault, probably for non-canonical address 0x6f6b6e696c2e756e: 0000 [#1] PREEMPT SMP PTI
  [   71.321540] CPU: 3 PID: 1201 Comm: kworker/3:2 Not tainted 5.6.0-rc1-00377-g2bb07f4e1d861 #192
  [   71.322746] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014
  [   71.324430] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
  [   71.325387] RIP: 0010:nft_set_elem_destroy+0xa5/0x110 [nf_tables]
  [   71.326164] Code: 89 d4 84 c0 74 0e 8b 77 44 0f b6 f8 48 01 df e8 41 ff ff ff 45 84 e4 74 36 44 0f b6 63 08 45 84 e4 74 2c 49 01 dc 49 8b 04 24 <48> 8b 40 38 48 85 c0 74 4f 48 89 e7 4c 8b
  [   71.328423] RSP: 0018:ffffc9000226fd90 EFLAGS: 00010282
  [   71.329225] RAX: 6f6b6e696c2e756e RBX: ffff88813ab79f60 RCX: ffff88813931b5a0
  [   71.330365] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88813ab79f9a
  [   71.331473] RBP: ffff88813ab79f60 R08: 0000000000000008 R09: 0000000000000000
  [   71.332627] R10: 000000000000021c R11: 0000000000000000 R12: ffff88813ab79fc2
  [   71.333615] R13: ffff88813b3adf50 R14: dead000000000100 R15: ffff88813931b8a0
  [   71.334596] FS:  0000000000000000(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
  [   71.335780] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   71.336577] CR2: 000055ac683710f0 CR3: 000000013a222003 CR4: 0000000000360ee0
  [   71.337533] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [   71.338557] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [   71.339718] Call Trace:
  [   71.340093]  nft_pipapo_destroy+0x7a/0x170 [nf_tables_set]
  [   71.340973]  nft_set_destroy+0x20/0x50 [nf_tables]
  [   71.341879]  nf_tables_trans_destroy_work+0x246/0x260 [nf_tables]
  [   71.342916]  process_one_work+0x1d5/0x3c0
  [   71.343601]  worker_thread+0x4a/0x3c0
  [   71.344229]  kthread+0xfb/0x130
  [   71.344780]  ? process_one_work+0x3c0/0x3c0
  [   71.345477]  ? kthread_park+0x90/0x90
  [   71.346129]  ret_from_fork+0x35/0x40
  [   71.346748] Modules linked in: nf_tables_set nf_tables nfnetlink 8021q [last unloaded: nfnetlink]
  [   71.348153] ---[ end trace 2eaa8149ca759bcc ]---
  [   71.349066] RIP: 0010:nft_set_elem_destroy+0xa5/0x110 [nf_tables]
  [   71.350016] Code: 89 d4 84 c0 74 0e 8b 77 44 0f b6 f8 48 01 df e8 41 ff ff ff 45 84 e4 74 36 44 0f b6 63 08 45 84 e4 74 2c 49 01 dc 49 8b 04 24 <48> 8b 40 38 48 85 c0 74 4f 48 89 e7 4c 8b
  [   71.350017] RSP: 0018:ffffc9000226fd90 EFLAGS: 00010282
  [   71.350019] RAX: 6f6b6e696c2e756e RBX: ffff88813ab79f60 RCX: ffff88813931b5a0
  [   71.350019] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88813ab79f9a
  [   71.350020] RBP: ffff88813ab79f60 R08: 0000000000000008 R09: 0000000000000000
  [   71.350021] R10: 000000000000021c R11: 0000000000000000 R12: ffff88813ab79fc2
  [   71.350022] R13: ffff88813b3adf50 R14: dead000000000100 R15: ffff88813931b8a0
  [   71.350025] FS:  0000000000000000(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
  [   71.350026] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   71.350027] CR2: 000055ac683710f0 CR3: 000000013a222003 CR4: 0000000000360ee0
  [   71.350028] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [   71.350028] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [   71.350030] Kernel panic - not syncing: Fatal exception
  [   71.350412] Kernel Offset: disabled
  [   71.365922] ---[ end Kernel panic - not syncing: Fatal exception ]---

which is caused by dangling elements that have been deactivated, but
never removed.

On a flush operation, nft_pipapo_walk() walks through all the elements
in the mapping table, which are then deactivated by nft_flush_set(),
one by one, and added to the commit list for removal. Element data is
then freed.

On transaction commit, nft_pipapo_remove() is called, and failed to
remove these elements, leading to the stale references in the mapping.
The first symptom of this, revealed by KASan, is a one-byte
use-after-free in subsequent calls to nft_pipapo_walk(), which is
usually not enough to trigger a panic. When stale elements are used
more heavily, though, such as double-free via nft_pipapo_destroy()
as in Phil's case, the problem becomes more noticeable.

The issue comes from that fact that, on a flush operation,
nft_pipapo_remove() won't get the actual key data via elem->key,
elements to be deleted upon commit won't be found by the lookup via
pipapo_get(), and removal will be skipped. Key data should be fetched
via nft_set_ext_key(), instead.

Reported-by: Phil Sutter <phil@nwl.cc>
Fixes: 3c4287f6 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

In br_dev_xmit() we perform vlan filtering in br_allowed_ingress() but
if the packet has the vlan header inside (e.g. bridge with disabled
tx-vlan-offload) then the vlan filtering code will use skb_vlan_untag()
to extract the vid before filtering which in turn calls pskb_may_pull()
and we may end up with a stale eth pointer. Moreover the cached eth header
pointer will generally be wrong after that operation. Remove the eth header
caching and just use eth_hdr() directly, the compiler does the right thing
and calculates it only once so we don't lose anything.

Fixes: 057658cb ("bridge: suppress arp pkts on BR_NEIGH_SUPPRESS ports")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

local->sta_mtx is held in __ieee80211_check_fast_rx_iface().
No need to use list_for_each_entry_rcu() as it also requires
a cond argument to avoid false lockdep warnings when not used in
RCU read-side section (with CONFIG_PROVE_RCU_LIST).
Therefore use list_for_each_entry();

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Link: https://lore.kernel.org/r/20200223143302.15390-1-madhuparnabhowmik10@gmail.com


Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We use that here, and do seem to get it through some recursive
include, but better include it explicitly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200224093814.1b9c258fec67.I45ac150d4e11c72eb263abec9f1f0c7add9bef2b@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>

devlink_dpipe_table_find() should be called under either
rcu_read_lock() or devlink->lock. devlink_dpipe_table_register()
calls devlink_dpipe_table_find() without holding the lock
and acquires it later. Therefore hold the devlink->lock
from the beginning of devlink_dpipe_table_register().

Suggested-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In a rare corner case the new logic for undo of SYNACK RTO could
result in triggering the warning in tcp_fastretrans_alert() that says:
        WARN_ON(tp->retrans_out != 0);

The warning looked like:

WARNING: CPU: 1 PID: 1 at net/ipv4/tcp_input.c:2818 tcp_ack+0x13e0/0x3270

The sequence that tickles this bug is:
 - Fast Open server receives TFO SYN with data, sends SYNACK
 - (client receives SYNACK and sends ACK, but ACK is lost)
 - server app sends some data packets
 - (N of the first data packets are lost)
 - server receives client ACK that has a TS ECR matching first SYNACK,
   and also SACKs suggesting the first N data packets were lost
    - server performs TS undo of SYNACK RTO, then immediately
      enters recovery
    - buggy behavior then performed a *second* undo that caused
      the connection to be in CA_Open with retrans_out != 0

Basically, the incoming ACK packet with SACK blocks causes us to first
undo the cwnd reduction from the SYNACK RTO, but then immediately
enters fast recovery, which then makes us eligible for undo again. And
then tcp_rcv_synrecv_state_fastopen() accidentally performs an undo
using a "mash-up" of state from two different loss recovery phases: it
uses the timestamp info from the ACK of the original SYNACK, and the
undo_marker from the fast recovery.

This fix refines the logic to only invoke the tcp_try_undo_loss()
inside tcp_rcv_synrecv_state_fastopen() if the connection is still in
CA_Loss.  If peer SACKs triggered fast recovery, then
tcp_rcv_synrecv_state_fastopen() can't safely undo.

Fixes: 794200d6 ("tcp: undo cwnd on Fast Open spurious SYNACK retransmit")
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently if attribute parsing fails and the genl family
does not support parallel operation, the error code returned
by __nlmsg_parse() is discarded by genl_family_rcv_msg_attrs_parse().

Be sure to report the error for all genl families.

Fixes: c10e6cf8 ("net: genetlink: push attrbuf allocation and parsing to a separate function")
Fixes: ab5b526d ("net: genetlink: always allocate separate attrs for dumpit ops")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Similarly to commit c543cb4a ("ipv4: ensure rcu_read_lock() in
ipv4_link_failure()"), __ip_options_compile() must be called under rcu
protection.

Fixes: 3da1ed7a ("net: avoid use IPCB in cipso_v4_error")
Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the forceadd option is enabled, the hash:* types should find and replace
the first entry in the bucket with the new one if there are no reuseable
(deleted or timed out) entries. However, the position index was just not set
to zero and remained the invalid -1 if there were no reuseable entries.

Reported-by:  <syzbot+6a86565c74ebe30aea18@syzkaller.appspotmail.com>
Fixes: 23c42a40 ("netfilter: ipset: Introduction of new commands and protocol version 7")
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>

In the case of huge hash:* types of sets, due to the single spinlock of
a set the processing of the whole set under spinlock protection could take
too long.

There were four places where the whole hash table of the set was processed
from bucket to bucket under holding the spinlock:

- During resizing a set, the original set was locked to exclude kernel side
  add/del element operations (userspace add/del is excluded by the
  nfnetlink mutex). The original set is actually just read during the
  resize, so the spinlocking is replaced with rcu locking of regions.
  However, thus there can be parallel kernel side add/del of entries.
  In order not to loose those operations a backlog is added and replayed
  after the successful resize.
- Garbage collection of timed out entries was also protected by the spinlock.
  In order not to lock too long, region locking is introduced and a single
  region is processed in one gc go. Also, the simple timer based gc running
  is replaced with a workqueue based solution. The internal book-keeping
  (number of elements, size of extensions) is moved to region level due to
  the region locking.
- Adding elements: when the max number of the elements is reached, the gc
  was called to evict the timed out entries. The new approach is that the gc
  is called just for the matching region, assuming that if the region
  (proportionally) seems to be full, then the whole set does. We could scan
  the other regions to check every entry under rcu locking, but for huge
  sets it'd mean a slowdown at adding elements.
- Listing the set header data: when the set was defined with timeout
  support, the garbage collector was called to clean up timed out entries
  to get the correct element numbers and set size values. Now the set is
  scanned to check non-timed out entries, without actually calling the gc
  for the whole set.

Thanks to Florian Westphal for helping me to solve the SOFTIRQ-safe ->
SOFTIRQ-unsafe lock order issues during working on the patch.

Reported-by:  <syzbot+4b0e9d4ff3cf117837e5@syzkaller.appspotmail.com>
Reported-by:  <syzbot+c27b8d5010f45c666ed1@syzkaller.appspotmail.com>
Reported-by:  <syzbot+68a806795ac89df3aa1c@syzkaller.appspotmail.com>
Fixes: 23c42a40 ("netfilter: ipset: Introduction of new commands and protocol version 7")
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>

The below-mentioned commit changed the code to unlock *inside*
the function, but previously the unlock was *outside*. It failed
to remove the outer unlock, however, leading to double unlock.

Fix this.

Fixes: 33483a6b ("mac80211: fix missing unlock on error in ieee80211_mark_sta_auth()")
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Link: https://lore.kernel.org/r/20200221104719.cce4741cf6eb.I671567b185c8a4c2409377e483fd149ce590f56d@changeid


[rewrite commit message to better explain what happened]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We may end up with a NULL reg_rule after the loop in
handle_channel_custom() if the bandwidth didn't fit,
check if this is the case and bail out if so.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200221104449.3b558a50201c.I4ad3725c4dacaefd2d18d3cc65ba6d18acd5dbfe@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If nl80211_parse_he_obss_pd() fails, we leak the previously
allocated ACL memory. Free it in this case.

Fixes: 796e90f4 ("cfg80211: add support for parsing OBBS_PD attributes")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200221104142.835aba4cdd14.I1923b55ba9989c57e13978f91f40bfdc45e60cbd@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since nl_groups is a u32 we can't bind more groups via ->bind
(netlink_bind) call, but netlink has supported more groups via
setsockopt() for a long time and thus nlk->ngroups could be over 32.
Recently I added support for per-vlan notifications and increased the
groups to 33 for NETLINK_ROUTE which exposed an old bug in the
netlink_bind() code causing out-of-bounds access on archs where unsigned
long is 32 bits via test_bit() on a local variable. Fix this by capping the
maximum groups in netlink_bind() to BITS_PER_TYPE(u32), effectively
capping them at 32 which is the minimum of allocated groups and the
maximum groups which can be bound via netlink_bind().

CC: Christophe Leroy <christophe.leroy@c-s.fr>
CC: Richard Guy Briggs <rgb@redhat.com>
Fixes: 4f520900 ("netlink: have netlink per-protocol bind function return an error code.")
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The description says 'If unsure, say N.' but
the module is built as M by default (once
the dependencies are satisfied).

When the module is selected (Y or M), it enables
NETFILTER_FAMILY_BRIDGE and SKB_EXTENSIONS
which alter kernel internal structures.

We (Android Studio Emulator) currently do not
use this module and think this it is more consistent
to have it disabled by default as opposite to
disabling it explicitly to prevent enabling
NETFILTER_FAMILY_BRIDGE and SKB_EXTENSIONS.

Signed-off-by: Roman Kiryanov <rkir@google.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.

net/openvswitch/flow_netlink.c: In function ‘validate_set’:
net/openvswitch/flow_netlink.c:2711:29: warning: statement will never be executed [-Wswitch-unreachable]
 2711 |  const struct ovs_key_ipv4 *ipv4_key;
      |                             ^~~~~~~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916



Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.

net/ipv6/ip6_gre.c: In function ‘ip6gre_err’:
net/ipv6/ip6_gre.c:440:32: warning: statement will never be executed [-Wswitch-unreachable]
  440 |   struct ipv6_tlv_tnl_enc_lim *tel;
      |                                ^~~

net/ipv6/ip6_tunnel.c: In function ‘ip6_tnl_err’:
net/ipv6/ip6_tunnel.c:520:32: warning: statement will never be executed [-Wswitch-unreachable]
  520 |   struct ipv6_tlv_tnl_enc_lim *tel;
      |                                ^~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916



Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.

net/core/skbuff.c: In function ‘skb_checksum_setup_ip’:
net/core/skbuff.c:4809:7: warning: statement will never be executed [-Wswitch-unreachable]
 4809 |   int err;
      |       ^~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916



Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

As of the below commit, udp sockets bound to a specific address can
coexist with one bound to the any addr for the same port.

The commit also phased out the use of socket hashing based only on
port (hslot), in favor of always hashing on {addr, port} (hslot2).

The change broke the following behavior with disconnect (AF_UNSPEC):

    server binds to 0.0.0.0:1337
    server connects to 127.0.0.1:80
    server disconnects
    client connects to 127.0.0.1:1337
    client sends "hello"
    server reads "hello"	// times out, packet did not find sk

On connect the server acquires a specific source addr suitable for
routing to its destination. On disconnect it reverts to the any addr.

The connect call triggers a rehash to a different hslot2. On
disconnect, add the same to return to the original hslot2.

Skip this step if the socket is going to be unhashed completely.

Fixes: 4cdeeee9 ("net: udp: prefer listeners bound to an address")
Reported-by: Pavel Roskin <plroskin@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Current code doesn't check if tcp sequence number is starting from (/after)
1st record's start sequnce number. It only checks if seq number is before
1st record's end sequnce number. This problem will always be a possibility
in re-transmit case. If a record which belongs to a requested seq number is
already deleted, tls_get_record will start looking into list and as per the
check it will look if seq number is before the end seq of 1st record, which
will always be true and will return 1st record always, it should in fact
return NULL.
As part of the fix, start looking each record only if the sequence number
lies in the list else return NULL.
There is one more check added, driver look for the start marker record to
handle tcp packets which are before the tls offload start sequence number,
hence return 1st record if the record is tls start marker and seq number is
before the 1st record's starting sequence number.

Fixes: e8f69799 ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Rohit Maheshwari <rohitm@chelsio.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

node_db is traversed using list_for_each_entry_rcu
outside an RCU read-side critical section but under the protection
of hsr->list_lock.

Hence, add corresponding lockdep expression to silence false-positive
warnings, and harden RCU lists.

Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

I originally used unlikely() in the if (match_only) clause, which
we hit on the mapping table for the last field in a set, to ensure
we avoid branching to the rest of for loop body, which is executed
more frequently.

However, Pablo reports, this is confusing as it gives the impression
that this is not a common case, and it's actually not the intended
usage of unlikely().

I couldn't observe any statistical difference in matching rates on
x864_64 and aarch64 without it, so just drop it.

Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fixes: 3c4287f6 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

In both insertion and lookup examples, the two element pointers
of rule mapping tables were swapped. Fix that.

Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fixes: 3c4287f6 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

hlist_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

hlist_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

hlist_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

hlist_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>