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973 commits

Author SHA1 Message Date
Paolo Abeni
fa8c776f4c mptcp: fix possible deadlock in subflow diag
commit d6a9608af9 upstream.

Syzbot and Eric reported a lockdep splat in the subflow diag:

   WARNING: possible circular locking dependency detected
   6.8.0-rc4-syzkaller-00212-g40b9385dd8e6 #0 Not tainted

   syz-executor.2/24141 is trying to acquire lock:
   ffff888045870130 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at:
   tcp_diag_put_ulp net/ipv4/tcp_diag.c:100 [inline]
   ffff888045870130 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at:
   tcp_diag_get_aux+0x738/0x830 net/ipv4/tcp_diag.c:137

   but task is already holding lock:
   ffffc9000135e488 (&h->lhash2[i].lock){+.+.}-{2:2}, at: spin_lock
   include/linux/spinlock.h:351 [inline]
   ffffc9000135e488 (&h->lhash2[i].lock){+.+.}-{2:2}, at:
   inet_diag_dump_icsk+0x39f/0x1f80 net/ipv4/inet_diag.c:1038

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #1 (&h->lhash2[i].lock){+.+.}-{2:2}:
   lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
   __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
   spin_lock include/linux/spinlock.h:351 [inline]
   __inet_hash+0x335/0xbe0 net/ipv4/inet_hashtables.c:743
   inet_csk_listen_start+0x23a/0x320 net/ipv4/inet_connection_sock.c:1261
   __inet_listen_sk+0x2a2/0x770 net/ipv4/af_inet.c:217
   inet_listen+0xa3/0x110 net/ipv4/af_inet.c:239
   rds_tcp_listen_init+0x3fd/0x5a0 net/rds/tcp_listen.c:316
   rds_tcp_init_net+0x141/0x320 net/rds/tcp.c:577
   ops_init+0x352/0x610 net/core/net_namespace.c:136
   __register_pernet_operations net/core/net_namespace.c:1214 [inline]
   register_pernet_operations+0x2cb/0x660 net/core/net_namespace.c:1283
   register_pernet_device+0x33/0x80 net/core/net_namespace.c:1370
   rds_tcp_init+0x62/0xd0 net/rds/tcp.c:735
   do_one_initcall+0x238/0x830 init/main.c:1236
   do_initcall_level+0x157/0x210 init/main.c:1298
   do_initcalls+0x3f/0x80 init/main.c:1314
   kernel_init_freeable+0x42f/0x5d0 init/main.c:1551
   kernel_init+0x1d/0x2a0 init/main.c:1441
   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242

   -> #0 (k-sk_lock-AF_INET6){+.+.}-{0:0}:
   check_prev_add kernel/locking/lockdep.c:3134 [inline]
   check_prevs_add kernel/locking/lockdep.c:3253 [inline]
   validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869
   __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
   lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
   lock_sock_fast include/net/sock.h:1723 [inline]
   subflow_get_info+0x166/0xd20 net/mptcp/diag.c:28
   tcp_diag_put_ulp net/ipv4/tcp_diag.c:100 [inline]
   tcp_diag_get_aux+0x738/0x830 net/ipv4/tcp_diag.c:137
   inet_sk_diag_fill+0x10ed/0x1e00 net/ipv4/inet_diag.c:345
   inet_diag_dump_icsk+0x55b/0x1f80 net/ipv4/inet_diag.c:1061
   __inet_diag_dump+0x211/0x3a0 net/ipv4/inet_diag.c:1263
   inet_diag_dump_compat+0x1c1/0x2d0 net/ipv4/inet_diag.c:1371
   netlink_dump+0x59b/0xc80 net/netlink/af_netlink.c:2264
   __netlink_dump_start+0x5df/0x790 net/netlink/af_netlink.c:2370
   netlink_dump_start include/linux/netlink.h:338 [inline]
   inet_diag_rcv_msg_compat+0x209/0x4c0 net/ipv4/inet_diag.c:1405
   sock_diag_rcv_msg+0xe7/0x410
   netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
   sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280
   netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
   netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
   netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
   sock_sendmsg_nosec net/socket.c:730 [inline]
   __sock_sendmsg+0x221/0x270 net/socket.c:745
   ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
   ___sys_sendmsg net/socket.c:2638 [inline]
   __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
   do_syscall_64+0xf9/0x240
   entry_SYSCALL_64_after_hwframe+0x6f/0x77

As noted by Eric we can break the lock dependency chain avoid
dumping any extended info for the mptcp subflow listener:
nothing actually useful is presented there.

Fixes: b8adb69a7d ("mptcp: fix lockless access in subflow ULP diag")
Cc: stable@vger.kernel.org
Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iJ=Oecw6OZDwmSYc9HJKQ_G32uN11L+oUcMu+TOD5Xiaw@mail.gmail.com/
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-9-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Davide Caratti
ce0809ada3 mptcp: fix double-free on socket dismantle
commit 10048689de upstream.

when MPTCP server accepts an incoming connection, it clones its listener
socket. However, the pointer to 'inet_opt' for the new socket has the same
value as the original one: as a consequence, on program exit it's possible
to observe the following splat:

  BUG: KASAN: double-free in inet_sock_destruct+0x54f/0x8b0
  Free of addr ffff888485950880 by task swapper/25/0

  CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Not tainted 6.8.0-rc1+ #609
  Hardware name: Supermicro SYS-6027R-72RF/X9DRH-7TF/7F/iTF/iF, BIOS 3.0  07/26/2013
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x32/0x50
   print_report+0xca/0x620
   kasan_report_invalid_free+0x64/0x90
   __kasan_slab_free+0x1aa/0x1f0
   kfree+0xed/0x2e0
   inet_sock_destruct+0x54f/0x8b0
   __sk_destruct+0x48/0x5b0
   rcu_do_batch+0x34e/0xd90
   rcu_core+0x559/0xac0
   __do_softirq+0x183/0x5a4
   irq_exit_rcu+0x12d/0x170
   sysvec_apic_timer_interrupt+0x6b/0x80
   </IRQ>
   <TASK>
   asm_sysvec_apic_timer_interrupt+0x16/0x20
  RIP: 0010:cpuidle_enter_state+0x175/0x300
  Code: 30 00 0f 84 1f 01 00 00 83 e8 01 83 f8 ff 75 e5 48 83 c4 18 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc fb 45 85 ed <0f> 89 60 ff ff ff 48 c1 e5 06 48 c7 43 18 00 00 00 00 48 83 44 2b
  RSP: 0018:ffff888481cf7d90 EFLAGS: 00000202
  RAX: 0000000000000000 RBX: ffff88887facddc8 RCX: 0000000000000000
  RDX: 1ffff1110ff588b1 RSI: 0000000000000019 RDI: ffff88887fac4588
  RBP: 0000000000000004 R08: 0000000000000002 R09: 0000000000043080
  R10: 0009b02ea273363f R11: ffff88887fabf42b R12: ffffffff932592e0
  R13: 0000000000000004 R14: 0000000000000000 R15: 00000022c880ec80
   cpuidle_enter+0x4a/0xa0
   do_idle+0x310/0x410
   cpu_startup_entry+0x51/0x60
   start_secondary+0x211/0x270
   secondary_startup_64_no_verify+0x184/0x18b
   </TASK>

  Allocated by task 6853:
   kasan_save_stack+0x1c/0x40
   kasan_save_track+0x10/0x30
   __kasan_kmalloc+0xa6/0xb0
   __kmalloc+0x1eb/0x450
   cipso_v4_sock_setattr+0x96/0x360
   netlbl_sock_setattr+0x132/0x1f0
   selinux_netlbl_socket_post_create+0x6c/0x110
   selinux_socket_post_create+0x37b/0x7f0
   security_socket_post_create+0x63/0xb0
   __sock_create+0x305/0x450
   __sys_socket_create.part.23+0xbd/0x130
   __sys_socket+0x37/0xb0
   __x64_sys_socket+0x6f/0xb0
   do_syscall_64+0x83/0x160
   entry_SYSCALL_64_after_hwframe+0x6e/0x76

  Freed by task 6858:
   kasan_save_stack+0x1c/0x40
   kasan_save_track+0x10/0x30
   kasan_save_free_info+0x3b/0x60
   __kasan_slab_free+0x12c/0x1f0
   kfree+0xed/0x2e0
   inet_sock_destruct+0x54f/0x8b0
   __sk_destruct+0x48/0x5b0
   subflow_ulp_release+0x1f0/0x250
   tcp_cleanup_ulp+0x6e/0x110
   tcp_v4_destroy_sock+0x5a/0x3a0
   inet_csk_destroy_sock+0x135/0x390
   tcp_fin+0x416/0x5c0
   tcp_data_queue+0x1bc8/0x4310
   tcp_rcv_state_process+0x15a3/0x47b0
   tcp_v4_do_rcv+0x2c1/0x990
   tcp_v4_rcv+0x41fb/0x5ed0
   ip_protocol_deliver_rcu+0x6d/0x9f0
   ip_local_deliver_finish+0x278/0x360
   ip_local_deliver+0x182/0x2c0
   ip_rcv+0xb5/0x1c0
   __netif_receive_skb_one_core+0x16e/0x1b0
   process_backlog+0x1e3/0x650
   __napi_poll+0xa6/0x500
   net_rx_action+0x740/0xbb0
   __do_softirq+0x183/0x5a4

  The buggy address belongs to the object at ffff888485950880
   which belongs to the cache kmalloc-64 of size 64
  The buggy address is located 0 bytes inside of
   64-byte region [ffff888485950880, ffff8884859508c0)

  The buggy address belongs to the physical page:
  page:0000000056d1e95e refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888485950700 pfn:0x485950
  flags: 0x57ffffc0000800(slab|node=1|zone=2|lastcpupid=0x1fffff)
  page_type: 0xffffffff()
  raw: 0057ffffc0000800 ffff88810004c640 ffffea00121b8ac0 dead000000000006
  raw: ffff888485950700 0000000000200019 00000001ffffffff 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffff888485950780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
   ffff888485950800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
  >ffff888485950880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                     ^
   ffff888485950900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
   ffff888485950980: 00 00 00 00 00 01 fc fc fc fc fc fc fc fc fc fc

Something similar (a refcount underflow) happens with CALIPSO/IPv6. Fix
this by duplicating IP / IPv6 options after clone, so that
ip{,6}_sock_destruct() doesn't end up freeing the same memory area twice.

Fixes: cf7da0d66c ("mptcp: Create SUBFLOW socket for incoming connections")
Cc: stable@vger.kernel.org
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-8-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Paolo Abeni
b609ecda2d mptcp: fix potential wake-up event loss
commit b111d8fbd2 upstream.

After the blamed commit below, the send buffer auto-tuning can
happen after that the mptcp_propagate_sndbuf() completes - via
the delegated action infrastructure.

We must check for write space even after such change or we risk
missing the wake-up event.

Fixes: 8005184fd1 ("mptcp: refactor sndbuf auto-tuning")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-6-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Paolo Abeni
ae5530ccd5 mptcp: fix snd_wnd initialization for passive socket
commit adf1bb78da upstream.

Such value should be inherited from the first subflow, but
passive sockets always used 'rsk_rcv_wnd'.

Fixes: 6f8a612a33 ("mptcp: keep track of advertised windows right edge")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-5-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Paolo Abeni
48428b07de mptcp: push at DSS boundaries
commit b9cd26f640 upstream.

when inserting not contiguous data in the subflow write queue,
the protocol creates a new skb and prevent the TCP stack from
merging it later with already queued skbs by setting the EOR marker.

Still no push flag is explicitly set at the end of previous GSO
packet, making the aggregation on the receiver side sub-optimal -
and packetdrill self-tests less predictable.

Explicitly mark the end of not contiguous DSS with the push flag.

Fixes: 6d0060f600 ("mptcp: Write MPTCP DSS headers to outgoing data packets")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-4-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Matthieu Baerts (NGI0)
fca4e6ab06 mptcp: avoid printing warning once on client side
commit 5b49c41ac8 upstream.

After the 'Fixes' commit mentioned below, the client side might print
the following warning once when a subflow is fully established at the
reception of any valid additional ack:

  MPTCP: bogus mpc option on established client sk

That's a normal situation, and no warning should be printed for that. We
can then skip the check when the label is used.

Fixes: e4a0fa47e8 ("mptcp: corner case locking for rx path fields initialization")
Cc: stable@vger.kernel.org
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-3-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Geliang Tang
a49ecbe8d0 mptcp: map v4 address to v6 when destroying subflow
commit 535d620ea5 upstream.

Address family of server side mismatches with that of client side, like
in "userspace pm add & remove address" test:

    userspace_pm_add_addr $ns1 10.0.2.1 10
    userspace_pm_rm_sf $ns1 "::ffff:10.0.2.1" $SUB_ESTABLISHED

That's because on the server side, the family is set to AF_INET6 and the
v4 address is mapped in a v6 one.

This patch fixes this issue. In mptcp_pm_nl_subflow_destroy_doit(), before
checking local address family with remote address family, map an IPv4
address to an IPv6 address if the pair is a v4-mapped address.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/387
Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-1-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Geliang Tang
7e7a81f9f2 mptcp: add needs_id for netlink appending addr
commit 584f389426 upstream.

Just the same as userspace PM, a new parameter needs_id is added for
in-kernel PM mptcp_pm_nl_append_new_local_addr() too.

Add a new helper mptcp_pm_has_addr_attr_id() to check whether an address
ID is set from PM or not.

In mptcp_pm_nl_get_local_id(), needs_id is always true, but in
mptcp_pm_nl_add_addr_doit(), pass mptcp_pm_has_addr_attr_id() to
needs_it.

Fixes: efd5a4c04e ("mptcp: add the address ID assignment bitmap")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:11 +01:00
Geliang Tang
6931f9029a mptcp: userspace pm send RM_ADDR for ID 0
commit 84c531f54a upstream.

This patch adds the ability to send RM_ADDR for local ID 0. Check
whether id 0 address is removed, if not, put id 0 into a removing
list, pass it to mptcp_pm_remove_addr() to remove id 0 address.

There is no reason not to allow the userspace to remove the initial
address (ID 0). This special case was not taken into account not
letting the userspace to delete all addresses as announced.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231025-send-net-next-20231025-v1-3-db8f25f798eb@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fixes: d9a4594eda ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE")
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:11 +01:00
Paolo Abeni
1ea7b252b4 mptcp: fix duplicate subflow creation
commit 045e9d8128 upstream.

Fullmesh endpoints could end-up unexpectedly generating duplicate
subflows - same local and remote addresses - when multiple incoming
ADD_ADDR are processed before the PM creates the subflow for the local
endpoints.

Address the issue explicitly checking for duplicates at subflow
creation time.

To avoid a quadratic computational complexity, track the unavailable
remote address ids in a temporary bitmap and initialize such bitmap
with the remote ids of all the existing subflows matching the local
address currently processed.

The above allows additionally replacing the existing code checking
for duplicate entry in the current set with a simple bit test
operation.

Fixes: 2843ff6f36 ("mptcp: remote addresses fullmesh")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/435
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:03 +01:00
Paolo Abeni
2dba5774e8 mptcp: fix data races on remote_id
commit 967d3c2712 upstream.

Similar to the previous patch, address the data race on
remote_id, adding the suitable ONCE annotations.

Fixes: bedee0b561 ("mptcp: address lookup improvements")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:03 +01:00
Paolo Abeni
ba2cf92250 mptcp: fix data races on local_id
commit a7cfe77663 upstream.

The local address id is accessed lockless by the NL PM, add
all the required ONCE annotation. There is a caveat: the local
id can be initialized late in the subflow life-cycle, and its
validity is controlled by the local_id_valid flag.

Remove such flag and encode the validity in the local_id field
itself with negative value before initialization. That allows
accessing the field consistently with a single read operation.

Fixes: 0ee4261a36 ("mptcp: implement mptcp_pm_remove_subflow")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:03 +01:00
Paolo Abeni
e074c8297e mptcp: fix lockless access in subflow ULP diag
commit b8adb69a7d upstream.

Since the introduction of the subflow ULP diag interface, the
dump callback accessed all the subflow data with lockless.

We need either to annotate all the read and write operation accordingly,
or acquire the subflow socket lock. Let's do latter, even if slower, to
avoid a diffstat havoc.

Fixes: 5147dfb508 ("mptcp: allow dumping subflow context to userspace")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:02 +01:00
Geliang Tang
176421d7af mptcp: add needs_id for userspace appending addr
commit 6c347be62a upstream.

When userspace PM requires to create an ID 0 subflow in "userspace pm
create id 0 subflow" test like this:

        userspace_pm_add_sf $ns2 10.0.3.2 0

An ID 1 subflow, in fact, is created.

Since in mptcp_pm_nl_append_new_local_addr(), 'id 0' will be treated as
no ID is set by userspace, and will allocate a new ID immediately:

     if (!e->addr.id)
             e->addr.id = find_next_zero_bit(pernet->id_bitmap,
                                             MPTCP_PM_MAX_ADDR_ID + 1,
                                             1);

To solve this issue, a new parameter needs_id is added for
mptcp_userspace_pm_append_new_local_addr() to distinguish between
whether userspace PM has set an ID 0 or whether userspace PM has
not set any address.

needs_id is true in mptcp_userspace_pm_get_local_id(), but false in
mptcp_pm_nl_announce_doit() and mptcp_pm_nl_subflow_create_doit().

Fixes: e5ed101a60 ("mptcp: userspace pm allow creating id 0 subflow")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:02 +01:00
Paolo Abeni
b45df837fe mptcp: corner case locking for rx path fields initialization
[ Upstream commit e4a0fa47e8 ]

Most MPTCP-level related fields are under the mptcp data lock
protection, but are written one-off without such lock at MPC
complete time, both for the client and the server

Leverage the mptcp_propagate_state() infrastructure to move such
initialization under the proper lock client-wise.

The server side critical init steps are done by
mptcp_subflow_fully_established(): ensure the caller properly held the
relevant lock, and avoid acquiring the same lock in the nested scopes.

There are no real potential races, as write access to such fields
is implicitly serialized by the MPTCP state machine; the primary
goal is consistency.

Fixes: d22f4988ff ("mptcp: process MP_CAPABLE data option")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Paolo Abeni
9326d0357a mptcp: fix more tx path fields initialization
[ Upstream commit 3f83d8a77e ]

The 'msk->write_seq' and 'msk->snd_nxt' are always updated under
the msk socket lock, except at MPC handshake completiont time.

Builds-up on the previous commit to move such init under the relevant
lock.

There are no known problems caused by the potential race, the
primary goal is consistency.

Fixes: 6d0060f600 ("mptcp: Write MPTCP DSS headers to outgoing data packets")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e8 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Geliang Tang
d52b3c2b29 mptcp: use mptcp_set_state
[ Upstream commit c693a85164 ]

This patch replaces all the 'inet_sk_state_store()' calls under net/mptcp
with the new helper mptcp_set_state().

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/460
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e8 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Geliang Tang
5655754731 mptcp: add CurrEstab MIB counter support
[ Upstream commit d9cd27b8cd ]

Add a new MIB counter named MPTCP_MIB_CURRESTAB to count current
established MPTCP connections, similar to TCP_MIB_CURRESTAB. This is
useful to quickly list the number of MPTCP connections without having to
iterate over all of them.

This patch adds a new helper function mptcp_set_state(): if the state
switches from or to ESTABLISHED state, this newly added counter is
incremented. This helper is going to be used in the following patch.

Similar to MPTCP_INC_STATS(), a new helper called MPTCP_DEC_STATS() is
also needed to decrement a MIB counter.

Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e8 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Paolo Abeni
4bfe217e07 mptcp: really cope with fastopen race
commit 337cebbd85 upstream.

Fastopen and PM-trigger subflow shutdown can race, as reported by
syzkaller.

In my first attempt to close such race, I missed the fact that
the subflow status can change again before the subflow_state_change
callback is invoked.

Address the issue additionally copying with all the states directly
reachable from TCP_FIN_WAIT1.

Fixes: 1e777f39b4 ("mptcp: add MSG_FASTOPEN sendmsg flag support")
Fixes: 4fd19a3070 ("mptcp: fix inconsistent state on fastopen race")
Cc: stable@vger.kernel.org
Reported-by: syzbot+c53d4d3ddb327e80bc51@syzkaller.appspotmail.com
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/458
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:01 +01:00
Geliang Tang
ed34dfa19d mptcp: check addrs list in userspace_pm_get_local_id
commit f012d796a6 upstream.

Before adding a new entry in mptcp_userspace_pm_get_local_id(), it's
better to check whether this address is already in userspace pm local
address list. If it's in the list, no need to add a new entry, just
return it's address ID and use this address.

Fixes: 8b20137012 ("mptcp: read attributes of addr entries managed by userspace PMs")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:00 +01:00
Paolo Abeni
a2d743747e mptcp: fix rcv space initialization
commit 013e3179db upstream.

mptcp_rcv_space_init() is supposed to happen under the msk socket
lock, but active msk socket does that without such protection.

Leverage the existing mptcp_propagate_state() helper to that extent.
We need to ensure mptcp_rcv_space_init will happen before
mptcp_rcv_space_adjust(), and the release_cb does not assure that:
explicitly check for such condition.

While at it, move the wnd_end initialization out of mptcp_rcv_space_init(),
it never belonged there.

Note that the race does not produce ill effect in practice, but
change allows cleaning-up and defying better the locking model.

Fixes: a6b118febb ("mptcp: add receive buffer auto-tuning")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:00 +01:00
Paolo Abeni
877a72e3b6 mptcp: drop the push_pending field
commit bdd70eb689 upstream.

Such field is there to avoid acquiring the data lock in a few spots,
but it adds complexity to the already non trivial locking schema.

All the relevant call sites (mptcp-level re-injection, set socket
options), are slow-path, drop such field in favor of 'cb_flags', adding
the relevant locking.

This patch could be seen as an improvement, instead of a fix. But it
simplifies the next patch. The 'Fixes' tag has been added to help having
this series backported to stable.

Fixes: e9d09baca6 ("mptcp: avoid atomic bit manipulation when possible")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:00 +01:00
Paolo Abeni
b609c783c5 mptcp: fix data re-injection from stale subflow
commit b6c620dc43 upstream.

When the MPTCP PM detects that a subflow is stale, all the packet
scheduler must re-inject all the mptcp-level unacked data. To avoid
acquiring unneeded locks, it first try to check if any unacked data
is present at all in the RTX queue, but such check is currently
broken, as it uses TCP-specific helper on an MPTCP socket.

Funnily enough fuzzers and static checkers are happy, as the accessed
memory still belongs to the mptcp_sock struct, and even from a
functional perspective the recovery completed successfully, as
the short-cut test always failed.

A recent unrelated TCP change - commit d5fed5addb ("tcp: reorganize
tcp_sock fast path variables") - exposed the issue, as the tcp field
reorganization makes the mptcp code always skip the re-inection.

Fix the issue dropping the bogus call: we are on a slow path, the early
optimization proved once again to be evil.

Fixes: 1e1d9d6f11 ("mptcp: handle pending data on closed subflow")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/468
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240131-upstream-net-20240131-mptcp-ci-issues-v1-1-4c1c11e571ff@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:24:59 +01:00
Paolo Abeni
72b45857b7 mptcp: relax check on MPC passive fallback
[ Upstream commit c0f5aec28e ]

While testing the blamed commit below, I was able to miss (!)
packetdrill failures in the fastopen test-cases.

On passive fastopen the child socket is created by incoming TCP MPC syn,
allow for both MPC_SYN and MPC_ACK header.

Fixes: 724b00c129 ("mptcp: refine opt_mp_capable determination")
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:59 -08:00
Eric Dumazet
d4368227ba mptcp: refine opt_mp_capable determination
[ Upstream commit 724b00c129 ]

OPTIONS_MPTCP_MPC is a combination of three flags.

It would be better to be strict about testing what
flag is expected, at least for code readability.

mptcp_parse_option() already makes the distinction.

- subflow_check_req() should use OPTION_MPTCP_MPC_SYN.

- mptcp_subflow_init_cookie_req() should use OPTION_MPTCP_MPC_ACK.

- subflow_finish_connect() should use OPTION_MPTCP_MPC_SYNACK

- subflow_syn_recv_sock should use OPTION_MPTCP_MPC_ACK

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Fixes: 74c7dfbee3 ("mptcp: consolidate in_opt sub-options fields in a bitmask")
Link: https://lore.kernel.org/r/20240111194917.4044654-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:57 -08:00
Eric Dumazet
c119bcd946 mptcp: use OPTION_MPTCP_MPJ_SYN in subflow_check_req()
[ Upstream commit 66ff70df1a ]

syzbot reported that subflow_check_req() was using uninitialized data in
subflow_check_req() [1]

This is because mp_opt.token is only set when OPTION_MPTCP_MPJ_SYN is also set.

While we are are it, fix mptcp_subflow_init_cookie_req()
to test for OPTION_MPTCP_MPJ_ACK.

[1]

BUG: KMSAN: uninit-value in subflow_token_join_request net/mptcp/subflow.c:91 [inline]
 BUG: KMSAN: uninit-value in subflow_check_req+0x1028/0x15d0 net/mptcp/subflow.c:209
  subflow_token_join_request net/mptcp/subflow.c:91 [inline]
  subflow_check_req+0x1028/0x15d0 net/mptcp/subflow.c:209
  subflow_v6_route_req+0x269/0x410 net/mptcp/subflow.c:367
  tcp_conn_request+0x153a/0x4240 net/ipv4/tcp_input.c:7164
 subflow_v6_conn_request+0x3ee/0x510
  tcp_rcv_state_process+0x2e1/0x4ac0 net/ipv4/tcp_input.c:6659
  tcp_v6_do_rcv+0x11bf/0x1fe0 net/ipv6/tcp_ipv6.c:1669
  tcp_v6_rcv+0x480b/0x4fb0 net/ipv6/tcp_ipv6.c:1900
  ip6_protocol_deliver_rcu+0xda6/0x2a60 net/ipv6/ip6_input.c:438
  ip6_input_finish net/ipv6/ip6_input.c:483 [inline]
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ip6_input+0x15d/0x430 net/ipv6/ip6_input.c:492
  dst_input include/net/dst.h:461 [inline]
  ip6_rcv_finish+0x5db/0x870 net/ipv6/ip6_input.c:79
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ipv6_rcv+0xda/0x390 net/ipv6/ip6_input.c:310
  __netif_receive_skb_one_core net/core/dev.c:5532 [inline]
  __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5646
  netif_receive_skb_internal net/core/dev.c:5732 [inline]
  netif_receive_skb+0x58/0x660 net/core/dev.c:5791
  tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555
  tun_get_user+0x53af/0x66d0 drivers/net/tun.c:2002
  tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
  call_write_iter include/linux/fs.h:2020 [inline]
  new_sync_write fs/read_write.c:491 [inline]
  vfs_write+0x8ef/0x1490 fs/read_write.c:584
  ksys_write+0x20f/0x4c0 fs/read_write.c:637
  __do_sys_write fs/read_write.c:649 [inline]
  __se_sys_write fs/read_write.c:646 [inline]
  __x64_sys_write+0x93/0xd0 fs/read_write.c:646
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Local variable mp_opt created at:
  subflow_check_req+0x6d/0x15d0 net/mptcp/subflow.c:145
  subflow_v6_route_req+0x269/0x410 net/mptcp/subflow.c:367

CPU: 1 PID: 5924 Comm: syz-executor.3 Not tainted 6.7.0-rc8-syzkaller-00055-g5eff55d725a4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Peter Krystad <peter.krystad@linux.intel.com>
Cc: Matthieu Baerts <matttbe@kernel.org>
Cc: Mat Martineau <martineau@kernel.org>
Cc: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240111194917.4044654-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:57 -08:00
Eric Dumazet
ad3e8f5c3d mptcp: use OPTION_MPTCP_MPJ_SYNACK in subflow_finish_connect()
[ Upstream commit be1d9d9d38 ]

subflow_finish_connect() uses four fields (backup, join_id, thmac, none)
that may contain garbage unless OPTION_MPTCP_MPJ_SYNACK has been set
in mptcp_parse_option()

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Peter Krystad <peter.krystad@linux.intel.com>
Cc: Matthieu Baerts <matttbe@kernel.org>
Cc: Mat Martineau <martineau@kernel.org>
Cc: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240111194917.4044654-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:56 -08:00
Eric Dumazet
4701d32823 mptcp: strict validation before using mp_opt->hmac
[ Upstream commit c1665273bd ]

mp_opt->hmac contains uninitialized data unless OPTION_MPTCP_MPJ_ACK
was set in mptcp_parse_option().

We must refine the condition before we call subflow_hmac_valid().

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Peter Krystad <peter.krystad@linux.intel.com>
Cc: Matthieu Baerts <matttbe@kernel.org>
Cc: Mat Martineau <martineau@kernel.org>
Cc: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240111194917.4044654-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:56 -08:00
Eric Dumazet
4029820677 mptcp: mptcp_parse_option() fix for MPTCPOPT_MP_JOIN
[ Upstream commit 89e23277f9 ]

mptcp_parse_option() currently sets OPTIONS_MPTCP_MPJ, for the three
possible cases handled for MPTCPOPT_MP_JOIN option.

OPTIONS_MPTCP_MPJ is the combination of three flags:
- OPTION_MPTCP_MPJ_SYN
- OPTION_MPTCP_MPJ_SYNACK
- OPTION_MPTCP_MPJ_ACK

This is a problem, because backup, join_id, token, nonce and/or hmac fields
could be left uninitialized in some cases.

Distinguish the three cases, as following patches will need this step.

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Peter Krystad <peter.krystad@linux.intel.com>
Cc: Matthieu Baerts <matttbe@kernel.org>
Cc: Mat Martineau <martineau@kernel.org>
Cc: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Simon Horman <horms@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240111194917.4044654-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:56 -08:00
Edward Adam Davis
5814deb5a5 mptcp: fix uninit-value in mptcp_incoming_options
[ Upstream commit 237ff253f2 ]

Added initialization use_ack to mptcp_parse_option().

Reported-by: syzbot+b834a6b2decad004cfa1@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-20 11:51:37 +01:00
Paolo Abeni
c25546cac3 mptcp: prevent tcp diag from closing listener subflows
commit 4c0288299f upstream.

The MPTCP protocol does not expect that any other entity could change
the first subflow status when such socket is listening.
Unfortunately the TCP diag interface allows aborting any TCP socket,
including MPTCP listeners subflows. As reported by syzbot, that trigger
a WARN() and could lead to later bigger trouble.

The MPTCP protocol needs to do some MPTCP-level cleanup actions to
properly shutdown the listener. To keep the fix simple, prevent
entirely the diag interface from stopping such listeners.

We could refine the diag callback in a later, larger patch targeting
net-next.

Fixes: 57fc0f1cea ("mptcp: ensure listener is unhashed before updating the sk status")
Cc: stable@vger.kernel.org
Reported-by: <syzbot+5a01c3a666e726bc8752@syzkaller.appspotmail.com>
Closes: https://lore.kernel.org/netdev/0000000000004f4579060c68431b@google.com/
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231226-upstream-net-20231226-mptcp-prevent-warn-v1-2-1404dcc431ea@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10 17:16:46 +01:00
Paolo Abeni
cf742d0955 mptcp: fix inconsistent state on fastopen race
[ Upstream commit 4fd19a3070 ]

The netlink PM can race with fastopen self-connect attempts, shutting
down the first subflow via:

MPTCP_PM_CMD_DEL_ADDR -> mptcp_nl_remove_id_zero_address ->
  mptcp_pm_nl_rm_subflow_received -> mptcp_close_ssk

and transitioning such subflow to FIN_WAIT1 status before the syn-ack
packet is processed. The MPTCP code does not react to such state change,
leaving the connection in not-fallback status and the subflow handshake
uncompleted, triggering the following splat:

  WARNING: CPU: 0 PID: 10630 at net/mptcp/subflow.c:1405 subflow_data_ready+0x39f/0x690 net/mptcp/subflow.c:1405
  Modules linked in:
  CPU: 0 PID: 10630 Comm: kworker/u4:11 Not tainted 6.6.0-syzkaller-14500-g1c41041124bd #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
  Workqueue: bat_events batadv_nc_worker
  RIP: 0010:subflow_data_ready+0x39f/0x690 net/mptcp/subflow.c:1405
  Code: 18 89 ee e8 e3 d2 21 f7 40 84 ed 75 1f e8 a9 d7 21 f7 44 89 fe bf 07 00 00 00 e8 0c d3 21 f7 41 83 ff 07 74 07 e8 91 d7 21 f7 <0f> 0b e8 8a d7 21 f7 48 89 df e8 d2 b2 ff ff 31 ff 89 c5 89 c6 e8
  RSP: 0018:ffffc90000007448 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff888031efc700 RCX: ffffffff8a65baf4
  RDX: ffff888043222140 RSI: ffffffff8a65baff RDI: 0000000000000005
  RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000007
  R10: 000000000000000b R11: 0000000000000000 R12: 1ffff92000000e89
  R13: ffff88807a534d80 R14: ffff888021c11a00 R15: 000000000000000b
  FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fa19a0ffc81 CR3: 000000007a2db000 CR4: 00000000003506f0
  DR0: 000000000000d8dd DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Call Trace:
   <IRQ>
   tcp_data_ready+0x14c/0x5b0 net/ipv4/tcp_input.c:5128
   tcp_data_queue+0x19c3/0x5190 net/ipv4/tcp_input.c:5208
   tcp_rcv_state_process+0x11ef/0x4e10 net/ipv4/tcp_input.c:6844
   tcp_v4_do_rcv+0x369/0xa10 net/ipv4/tcp_ipv4.c:1929
   tcp_v4_rcv+0x3888/0x3b30 net/ipv4/tcp_ipv4.c:2329
   ip_protocol_deliver_rcu+0x9f/0x480 net/ipv4/ip_input.c:205
   ip_local_deliver_finish+0x2e4/0x510 net/ipv4/ip_input.c:233
   NF_HOOK include/linux/netfilter.h:314 [inline]
   NF_HOOK include/linux/netfilter.h:308 [inline]
   ip_local_deliver+0x1b6/0x550 net/ipv4/ip_input.c:254
   dst_input include/net/dst.h:461 [inline]
   ip_rcv_finish+0x1c4/0x2e0 net/ipv4/ip_input.c:449
   NF_HOOK include/linux/netfilter.h:314 [inline]
   NF_HOOK include/linux/netfilter.h:308 [inline]
   ip_rcv+0xce/0x440 net/ipv4/ip_input.c:569
   __netif_receive_skb_one_core+0x115/0x180 net/core/dev.c:5527
   __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5641
   process_backlog+0x101/0x6b0 net/core/dev.c:5969
   __napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6531
   napi_poll net/core/dev.c:6600 [inline]
   net_rx_action+0x956/0xe90 net/core/dev.c:6733
   __do_softirq+0x21a/0x968 kernel/softirq.c:553
   do_softirq kernel/softirq.c:454 [inline]
   do_softirq+0xaa/0xe0 kernel/softirq.c:441
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:381
   spin_unlock_bh include/linux/spinlock.h:396 [inline]
   batadv_nc_purge_paths+0x1ce/0x3c0 net/batman-adv/network-coding.c:471
   batadv_nc_worker+0x9b1/0x10e0 net/batman-adv/network-coding.c:722
   process_one_work+0x884/0x15c0 kernel/workqueue.c:2630
   process_scheduled_works kernel/workqueue.c:2703 [inline]
   worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
   kthread+0x33c/0x440 kernel/kthread.c:388
   ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
   </TASK>

To address the issue, catch the racing subflow state change and
use it to cause the MPTCP fallback. Such fallback is also used to
cause the first subflow state propagation to the msk socket via
mptcp_set_connected(). After this change, the first subflow can
additionally propagate the TCP_FIN_WAIT1 state, so rename the
helper accordingly.

Finally, if the state propagation is delayed to the msk release
callback, the first subflow can change to a different state in between.
Cache the relevant target state in a new msk-level field and use
such value to update the msk state at release time.

Fixes: 1e777f39b4 ("mptcp: add MSG_FASTOPEN sendmsg flag support")
Cc: stable@vger.kernel.org
Reported-by: <syzbot+c53d4d3ddb327e80bc51@syzkaller.appspotmail.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/458
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-05 15:19:42 +01:00
Paolo Abeni
44ee4764c6 mptcp: fix possible NULL pointer dereference on close
[ Upstream commit d109a77672 ]

After the blamed commit below, the MPTCP release callback can
dereference the first subflow pointer via __mptcp_set_connected()
and send buffer auto-tuning. Such pointer is always expected to be
valid, except at socket destruction time, when the first subflow is
deleted and the pointer zeroed.

If the connect event is handled by the release callback while the
msk socket is finally released, MPTCP hits the following splat:

  general protection fault, probably for non-canonical address 0xdffffc00000000f2: 0000 [#1] PREEMPT SMP KASAN
  KASAN: null-ptr-deref in range [0x0000000000000790-0x0000000000000797]
  CPU: 1 PID: 26719 Comm: syz-executor.2 Not tainted 6.6.0-syzkaller-10102-gff269e2cd5ad #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
  RIP: 0010:mptcp_subflow_ctx net/mptcp/protocol.h:542 [inline]
  RIP: 0010:__mptcp_propagate_sndbuf net/mptcp/protocol.h:813 [inline]
  RIP: 0010:__mptcp_set_connected+0x57/0x3e0 net/mptcp/subflow.c:424
  RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8a62323c
  RDX: 00000000000000f2 RSI: ffffffff8a630116 RDI: 0000000000000790
  RBP: ffff88803334b100 R08: 0000000000000001 R09: 0000000000000000
  R10: 0000000000000001 R11: 0000000000000034 R12: ffff88803334b198
  R13: ffff888054f0b018 R14: 0000000000000000 R15: ffff88803334b100
  FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fbcb4f75198 CR3: 000000006afb5000 CR4: 00000000003506f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   mptcp_release_cb+0xa2c/0xc40 net/mptcp/protocol.c:3405
   release_sock+0xba/0x1f0 net/core/sock.c:3537
   mptcp_close+0x32/0xf0 net/mptcp/protocol.c:3084
   inet_release+0x132/0x270 net/ipv4/af_inet.c:433
   inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:485
   __sock_release+0xae/0x260 net/socket.c:659
   sock_close+0x1c/0x20 net/socket.c:1419
   __fput+0x270/0xbb0 fs/file_table.c:394
   task_work_run+0x14d/0x240 kernel/task_work.c:180
   exit_task_work include/linux/task_work.h:38 [inline]
   do_exit+0xa92/0x2a20 kernel/exit.c:876
   do_group_exit+0xd4/0x2a0 kernel/exit.c:1026
   get_signal+0x23ba/0x2790 kernel/signal.c:2900
   arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309
   exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
   exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
   __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
   syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296
   do_syscall_64+0x4b/0x110 arch/x86/entry/common.c:88
   entry_SYSCALL_64_after_hwframe+0x63/0x6b
  RIP: 0033:0x7fb515e7cae9
  Code: Unable to access opcode bytes at 0x7fb515e7cabf.
  RSP: 002b:00007fb516c560c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
  RAX: 000000000000003c RBX: 00007fb515f9c120 RCX: 00007fb515e7cae9
  RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000006
  RBP: 00007fb515ec847a R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  R13: 000000000000006e R14: 00007fb515f9c120 R15: 00007ffc631eb968
   </TASK>

To avoid sparkling unneeded conditionals, address the issue explicitly
checking msk->first only in the critical place.

Fixes: 8005184fd1 ("mptcp: refactor sndbuf auto-tuning")
Cc: stable@vger.kernel.org
Reported-by: <syzbot+9dfbaedb6e6baca57a32@syzkaller.appspotmail.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/454
Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iLZUA6S2a=K8GObnS62KK6Jt4B7PsAs7meMFooM8xaTgw@mail.gmail.com/
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231114-upstream-net-20231113-mptcp-misc-fixes-6-7-rc2-v1-2-7b9cd6a7b7f4@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 4fd19a3070 ("mptcp: fix inconsistent state on fastopen race")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-05 15:19:41 +01:00
Paolo Abeni
34c7757aa5 mptcp: refactor sndbuf auto-tuning
[ Upstream commit 8005184fd1 ]

The MPTCP protocol account for the data enqueued on all the subflows
to the main socket send buffer, while the send buffer auto-tuning
algorithm set the main socket send buffer size as the max size among
the subflows.

That causes bad performances when at least one subflow is sndbuf
limited, e.g. due to very high latency, as the MPTCP scheduler can't
even fill such buffer.

Change the send-buffer auto-tuning algorithm to compute the main socket
send buffer size as the sum of all the subflows buffer size.

Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-2-v1-9-9dc60939d371@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 4fd19a3070 ("mptcp: fix inconsistent state on fastopen race")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-05 15:19:41 +01:00
Paolo Abeni
dfac7f073b mptcp: fix setsockopt(IP_TOS) subflow locking
commit 7679d34f97 upstream.

The MPTCP implementation of the IP_TOS socket option uses the lockless
variant of the TOS manipulation helper and does not hold such lock at
the helper invocation time.

Add the required locking.

Fixes: ffcacff87c ("mptcp: Support for IP_TOS for MPTCP setsockopt()")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/457
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231114-upstream-net-20231113-mptcp-misc-fixes-6-7-rc2-v1-4-7b9cd6a7b7f4@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:20:14 +00:00
Geliang Tang
43fa3b0d7b mptcp: add validity check for sending RM_ADDR
commit 8df220b292 upstream.

This patch adds the validity check for sending RM_ADDRs for userspace PM
in mptcp_pm_remove_addrs(), only send a RM_ADDR when the address is in the
anno_list or conn_list.

Fixes: 8b1c94da1e ("mptcp: only send RM_ADDR in nl_cmd_remove")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231114-upstream-net-20231113-mptcp-misc-fixes-6-7-rc2-v1-3-7b9cd6a7b7f4@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:20:13 +00:00
Paolo Abeni
57ced2eb77 mptcp: deal with large GSO size
commit 9fce92f050 upstream.

After the blamed commit below, the TCP sockets (and the MPTCP subflows)
can build egress packets larger than 64K. That exceeds the maximum DSS
data size, the length being misrepresent on the wire and the stream being
corrupted, as later observed on the receiver:

  WARNING: CPU: 0 PID: 9696 at net/mptcp/protocol.c:705 __mptcp_move_skbs_from_subflow+0x2604/0x26e0
  CPU: 0 PID: 9696 Comm: syz-executor.7 Not tainted 6.6.0-rc5-gcd8bdf563d46 #45
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
  netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'.
  RIP: 0010:__mptcp_move_skbs_from_subflow+0x2604/0x26e0 net/mptcp/protocol.c:705
  RSP: 0018:ffffc90000006e80 EFLAGS: 00010246
  RAX: ffffffff83e9f674 RBX: ffff88802f45d870 RCX: ffff888102ad0000
  netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'.
  RDX: 0000000080000303 RSI: 0000000000013908 RDI: 0000000000003908
  RBP: ffffc90000007110 R08: ffffffff83e9e078 R09: 1ffff1100e548c8a
  R10: dffffc0000000000 R11: ffffed100e548c8b R12: 0000000000013908
  R13: dffffc0000000000 R14: 0000000000003908 R15: 000000000031cf29
  FS:  00007f239c47e700(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f239c45cd78 CR3: 000000006a66c006 CR4: 0000000000770ef0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
  PKRU: 55555554
  Call Trace:
   <IRQ>
   mptcp_data_ready+0x263/0xac0 net/mptcp/protocol.c:819
   subflow_data_ready+0x268/0x6d0 net/mptcp/subflow.c:1409
   tcp_data_queue+0x21a1/0x7a60 net/ipv4/tcp_input.c:5151
   tcp_rcv_established+0x950/0x1d90 net/ipv4/tcp_input.c:6098
   tcp_v6_do_rcv+0x554/0x12f0 net/ipv6/tcp_ipv6.c:1483
   tcp_v6_rcv+0x2e26/0x3810 net/ipv6/tcp_ipv6.c:1749
   ip6_protocol_deliver_rcu+0xd6b/0x1ae0 net/ipv6/ip6_input.c:438
   ip6_input+0x1c5/0x470 net/ipv6/ip6_input.c:483
   ipv6_rcv+0xef/0x2c0 include/linux/netfilter.h:304
   __netif_receive_skb+0x1ea/0x6a0 net/core/dev.c:5532
   process_backlog+0x353/0x660 net/core/dev.c:5974
   __napi_poll+0xc6/0x5a0 net/core/dev.c:6536
   net_rx_action+0x6a0/0xfd0 net/core/dev.c:6603
   __do_softirq+0x184/0x524 kernel/softirq.c:553
   do_softirq+0xdd/0x130 kernel/softirq.c:454

Address the issue explicitly bounding the maximum GSO size to what MPTCP
actually allows.

Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/450
Fixes: 7c4e983c4f ("net: allow gso_max_size to exceed 65536")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231114-upstream-net-20231113-mptcp-misc-fixes-6-7-rc2-v1-1-7b9cd6a7b7f4@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 17:20:13 +00:00
Paolo Abeni
eede8e07f0 mptcp: properly account fastopen data
[ Upstream commit bf0e96108f ]

Currently the socket level counter aggregating the received data
does not take in account the data received via fastopen.

Address the issue updating the counter as required.

Fixes: 38967f424b ("mptcp: track some aggregate data counters")
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-2-v1-2-9dc60939d371@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:59:03 +01:00
Geliang Tang
14c56686a6 mptcp: avoid sending RST when closing the initial subflow
When closing the first subflow, the MPTCP protocol unconditionally
calls tcp_disconnect(), which in turn generates a reset if the subflow
is established.

That is unexpected and different from what MPTCP does with MPJ
subflows, where resets are generated only on FASTCLOSE and other edge
scenarios.

We can't reuse for the first subflow the same code in place for MPJ
subflows, as MPTCP clean them up completely via a tcp_close() call,
while must keep the first subflow socket alive for later re-usage, due
to implementation constraints.

This patch adds a new helper __mptcp_subflow_disconnect() that
encapsulates, a logic similar to tcp_close, issuing a reset only when
the MPTCP_CF_FASTCLOSE flag is set, and performing a clean shutdown
otherwise.

Fixes: c2b2ae3925 ("mptcp: handle correctly disconnect() failures")
Cc: stable@vger.kernel.org
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-4-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-19 09:10:00 -07:00
Paolo Abeni
72377ab2d6 mptcp: more conservative check for zero probes
Christoph reported that the MPTCP protocol can find the subflow-level
write queue unexpectedly not empty while crafting a zero-window probe,
hitting a warning:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 188 at net/mptcp/protocol.c:1312 mptcp_sendmsg_frag+0xc06/0xe70
Modules linked in:
CPU: 0 PID: 188 Comm: kworker/0:2 Not tainted 6.6.0-rc2-g1176aa719d7a #47
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:mptcp_sendmsg_frag+0xc06/0xe70 net/mptcp/protocol.c:1312
RAX: 47d0530de347ff6a RBX: 47d0530de347ff6b RCX: ffff8881015d3c00
RDX: ffff8881015d3c00 RSI: 47d0530de347ff6b RDI: 47d0530de347ff6b
RBP: 47d0530de347ff6b R08: ffffffff8243c6a8 R09: ffffffff82042d9c
R10: 0000000000000002 R11: ffffffff82056850 R12: ffff88812a13d580
R13: 0000000000000001 R14: ffff88812b375e50 R15: ffff88812bbf3200
FS:  0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000695118 CR3: 0000000115dfc001 CR4: 0000000000170ef0
Call Trace:
 <TASK>
 __subflow_push_pending+0xa4/0x420 net/mptcp/protocol.c:1545
 __mptcp_push_pending+0x128/0x3b0 net/mptcp/protocol.c:1614
 mptcp_release_cb+0x218/0x5b0 net/mptcp/protocol.c:3391
 release_sock+0xf6/0x100 net/core/sock.c:3521
 mptcp_worker+0x6e8/0x8f0 net/mptcp/protocol.c:2746
 process_scheduled_works+0x341/0x690 kernel/workqueue.c:2630
 worker_thread+0x3a7/0x610 kernel/workqueue.c:2784
 kthread+0x143/0x180 kernel/kthread.c:388
 ret_from_fork+0x4d/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:304
 </TASK>

The root cause of the issue is that expectations are wrong: e.g. due
to MPTCP-level re-injection we can hit the critical condition.

Explicitly avoid the zero-window probe when the subflow write queue
is not empty and drop the related warnings.

Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/444
Fixes: f70cad1085 ("mptcp: stop relying on tcp_tx_skb_cache")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231018-send-net-20231018-v1-3-17ecb002e41d@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-19 09:10:00 -07:00
Paolo Abeni
419ce133ab tcp: allow again tcp_disconnect() when threads are waiting
As reported by Tom, .NET and applications build on top of it rely
on connect(AF_UNSPEC) to async cancel pending I/O operations on TCP
socket.

The blamed commit below caused a regression, as such cancellation
can now fail.

As suggested by Eric, this change addresses the problem explicitly
causing blocking I/O operation to terminate immediately (with an error)
when a concurrent disconnect() is executed.

Instead of tracking the number of threads blocked on a given socket,
track the number of disconnect() issued on such socket. If such counter
changes after a blocking operation releasing and re-acquiring the socket
lock, error out the current operation.

Fixes: 4faeee0cf8 ("tcp: deny tcp_disconnect() when threads are waiting")
Reported-by: Tom Deseyn <tdeseyn@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1886305
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/f3b95e47e3dbed840960548aebaa8d954372db41.1697008693.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-13 16:49:32 -07:00
Geliang Tang
e5ed101a60 mptcp: userspace pm allow creating id 0 subflow
This patch drops id 0 limitation in mptcp_nl_cmd_sf_create() to allow
creating additional subflows with the local addr ID 0.

There is no reason not to allow additional subflows from this local
address: we should be able to create new subflows from the initial
endpoint. This limitation was breaking fullmesh support from userspace.

Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/391
Cc: stable@vger.kernel.org
Suggested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231004-send-net-20231004-v1-2-28de4ac663ae@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-05 09:34:32 -07:00
Paolo Abeni
a5efdbcece mptcp: fix delegated action races
The delegated action infrastructure is prone to the following
race: different CPUs can try to schedule different delegated
actions on the same subflow at the same time.

Each of them will check different bits via mptcp_subflow_delegate(),
and will try to schedule the action on the related per-cpu napi
instance.

Depending on the timing, both can observe an empty delegated list
node, causing the same entry to be added simultaneously on two different
lists.

The root cause is that the delegated actions infra does not provide
a single synchronization point. Address the issue reserving an additional
bit to mark the subflow as scheduled for delegation. Acquiring such bit
guarantee the caller to own the delegated list node, and being able to
safely schedule the subflow.

Clear such bit only when the subflow scheduling is completed, ensuring
proper barrier in place.

Additionally swap the meaning of the delegated_action bitmask, to allow
the usage of the existing helper to set multiple bit at once.

Fixes: bcd9773431 ("mptcp: use delegate action to schedule 3rd ack retrans")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231004-send-net-20231004-v1-1-28de4ac663ae@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-05 09:34:31 -07:00
Paolo Abeni
27e5ccc2d5 mptcp: fix dangling connection hang-up
According to RFC 8684 section 3.3:

  A connection is not closed unless [...] or an implementation-specific
  connection-level send timeout.

Currently the MPTCP protocol does not implement such timeout, and
connection timing-out at the TCP-level never move to close state.

Introduces a catch-up condition at subflow close time to move the
MPTCP socket to close, too.

That additionally allows removing similar existing inside the worker.

Finally, allow some additional timeout for plain ESTABLISHED mptcp
sockets, as the protocol allows creating new subflows even at that
point and making the connection functional again.

This issue is actually present since the beginning, but it is basically
impossible to solve without a long chain of functional pre-requisites
topped by commit bbd49d114d ("mptcp: consolidate transition to
TCP_CLOSE in mptcp_do_fastclose()"). When backporting this current
patch, please also backport this other commit as well.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/430
Fixes: e16163b6e2 ("mptcp: refactor shutdown and close")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-18 12:47:56 +01:00
Paolo Abeni
f6909dc1c1 mptcp: rename timer related helper to less confusing names
The msk socket uses to different timeout to track close related
events and retransmissions. The existing helpers do not indicate
clearly which timer they actually touch, making the related code
quite confusing.

Change the existing helpers name to avoid such confusion. No
functional change intended.

This patch is linked to the next one ("mptcp: fix dangling connection
hang-up"). The two patches are supposed to be backported together.

Cc: stable@vger.kernel.org # v5.11+
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-18 12:47:56 +01:00
Paolo Abeni
9f1a98813b mptcp: process pending subflow error on close
On incoming TCP reset, subflow closing could happen before error
propagation. That in turn could cause the socket error being ignored,
and a missing socket state transition, as reported by Daire-Byrne.

Address the issues explicitly checking for subflow socket error at
close time. To avoid code duplication, factor-out of __mptcp_error_report()
a new helper implementing the relevant bits.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/429
Fixes: 15cc104533 ("mptcp: deliver ssk errors to msk")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-18 12:47:56 +01:00
Paolo Abeni
d5fbeff1ab mptcp: move __mptcp_error_report in protocol.c
This will simplify the next patch ("mptcp: process pending subflow error
on close").

No functional change intended.

Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-18 12:47:56 +01:00
Paolo Abeni
6bec041147 mptcp: fix bogus receive window shrinkage with multiple subflows
In case multiple subflows race to update the mptcp-level receive
window, the subflow losing the race should use the window value
provided by the "winning" subflow to update it's own tcp-level
rcv_wnd.

To such goal, the current code bogusly uses the mptcp-level rcv_wnd
value as observed before the update attempt. On unlucky circumstances
that may lead to TCP-level window shrinkage, and stall the other end.

Address the issue feeding to the rcv wnd update the correct value.

Fixes: f3589be0c4 ("mptcp: never shrink offered window")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/427
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-18 12:47:55 +01:00
Linus Torvalds
73be7fb14e Including fixes from netfilter and bpf.
Current release - regressions:
 
  - eth: stmmac: fix failure to probe without MAC interface specified
 
 Current release - new code bugs:
 
  - docs: netlink: fix missing classic_netlink doc reference
 
 Previous releases - regressions:
 
  - deal with integer overflows in kmalloc_reserve()
 
  - use sk_forward_alloc_get() in sk_get_meminfo()
 
  - bpf_sk_storage: fix the missing uncharge in sk_omem_alloc
 
  - fib: avoid warn splat in flow dissector after packet mangling
 
  - skb_segment: call zero copy functions before using skbuff frags
 
  - eth: sfc: check for zero length in EF10 RX prefix
 
 Previous releases - always broken:
 
  - af_unix: fix msg_controllen test in scm_pidfd_recv() for
    MSG_CMSG_COMPAT
 
  - xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()
 
  - netfilter:
    - nft_exthdr: fix non-linear header modification
    - xt_u32, xt_sctp: validate user space input
    - nftables: exthdr: fix 4-byte stack OOB write
    - nfnetlink_osf: avoid OOB read
    - one more fix for the garbage collection work from last release
 
  - igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU
 
  - bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t
 
  - handshake: fix null-deref in handshake_nl_done_doit()
 
  - ip: ignore dst hint for multipath routes to ensure packets
    are hashed across the nexthops
 
  - phy: micrel:
    - correct bit assignments for cable test errata
    - disable EEE according to the KSZ9477 errata
 
 Misc:
 
  - docs/bpf: document compile-once-run-everywhere (CO-RE) relocations
 
  - Revert "net: macsec: preserve ingress frame ordering", it appears
    to have been developed against an older kernel, problem doesn't
    exist upstream
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking updates from Jakub Kicinski:
 "Including fixes from netfilter and bpf.

  Current release - regressions:

   - eth: stmmac: fix failure to probe without MAC interface specified

  Current release - new code bugs:

   - docs: netlink: fix missing classic_netlink doc reference

  Previous releases - regressions:

   - deal with integer overflows in kmalloc_reserve()

   - use sk_forward_alloc_get() in sk_get_meminfo()

   - bpf_sk_storage: fix the missing uncharge in sk_omem_alloc

   - fib: avoid warn splat in flow dissector after packet mangling

   - skb_segment: call zero copy functions before using skbuff frags

   - eth: sfc: check for zero length in EF10 RX prefix

  Previous releases - always broken:

   - af_unix: fix msg_controllen test in scm_pidfd_recv() for
     MSG_CMSG_COMPAT

   - xsk: fix xsk_build_skb() dereferencing possible ERR_PTR()

   - netfilter:
      - nft_exthdr: fix non-linear header modification
      - xt_u32, xt_sctp: validate user space input
      - nftables: exthdr: fix 4-byte stack OOB write
      - nfnetlink_osf: avoid OOB read
      - one more fix for the garbage collection work from last release

   - igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU

   - bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t

   - handshake: fix null-deref in handshake_nl_done_doit()

   - ip: ignore dst hint for multipath routes to ensure packets are
     hashed across the nexthops

   - phy: micrel:
      - correct bit assignments for cable test errata
      - disable EEE according to the KSZ9477 errata

  Misc:

   - docs/bpf: document compile-once-run-everywhere (CO-RE) relocations

   - Revert "net: macsec: preserve ingress frame ordering", it appears
     to have been developed against an older kernel, problem doesn't
     exist upstream"

* tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits)
  net: enetc: distinguish error from valid pointers in enetc_fixup_clear_rss_rfs()
  Revert "net: team: do not use dynamic lockdep key"
  net: hns3: remove GSO partial feature bit
  net: hns3: fix the port information display when sfp is absent
  net: hns3: fix invalid mutex between tc qdisc and dcb ets command issue
  net: hns3: fix debugfs concurrency issue between kfree buffer and read
  net: hns3: fix byte order conversion issue in hclge_dbg_fd_tcam_read()
  net: hns3: Support query tx timeout threshold by debugfs
  net: hns3: fix tx timeout issue
  net: phy: Provide Module 4 KSZ9477 errata (DS80000754C)
  netfilter: nf_tables: Unbreak audit log reset
  netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c
  netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction
  netfilter: nf_tables: uapi: Describe NFTA_RULE_CHAIN_ID
  netfilter: nfnetlink_osf: avoid OOB read
  netfilter: nftables: exthdr: fix 4-byte stack OOB write
  selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc
  bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc
  bpf: bpf_sk_storage: Fix invalid wait context lockdep report
  s390/bpf: Pass through tail call counter in trampolines
  ...
2023-09-07 18:33:07 -07:00
Eric Dumazet
9531e4a83f mptcp: annotate data-races around msk->rmem_fwd_alloc
msk->rmem_fwd_alloc can be read locklessly.

Add mptcp_rmem_fwd_alloc_add(), similar to sk_forward_alloc_add(),
and appropriate READ_ONCE()/WRITE_ONCE() annotations.

Fixes: 6511882cdd ("mptcp: allocate fwd memory separately on the rx and tx path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-01 07:27:33 +01:00