wireguard-linux/net/mptcp, branch jd/unified-crypt-queue

mptcp: fix double-unlock in mptcp_poll

2020-04-13T04:04:08Z

mptcp_connect/28740 is trying to release lock (sk_lock-AF_INET) at: [] mptcp_poll+0xb9/0x550 but there are no more locks to release! Call Trace: lock_release+0x50f/0x750 release_sock+0x171/0x1b0 mptcp_poll+0xb9/0x550 sock_poll+0x157/0x470 ? get_net_ns+0xb0/0xb0 do_sys_poll+0x63c/0xdd0 Problem is that __mptcp_tcp_fallback() releases the mptcp socket lock, but after recent change it doesn't do this in all of its return paths. To fix this, remove the unlock from __mptcp_tcp_fallback() and always do the unlock in the caller. Also add a small comment as to why we have this __mptcp_needs_tcp_fallback(). Fixes: 0b4f33def7bbde ("mptcp: fix tcp fallback crash") Reported-by: syzbot+e56606435b7bfeea8cf5@syzkaller.appspotmail.com Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

mptcp: add some missing pr_fmt defines

2020-04-03T23:06:32Z

Some of the mptcp logs didn't print out the format string: [ 185.651493] DSS [ 185.651494] data_fin=0 dsn64=0 use_map=0 ack64=1 use_ack=1 [ 185.651494] data_ack=13792750332298763796 [ 185.651495] MPTCP: msk=00000000c4b81cfc ssk=000000009743af53 data_avail=0 skb=0000000063dc595d [ 185.651495] MPTCP: msk=00000000c4b81cfc ssk=000000009743af53 status=0 [ 185.651495] MPTCP: msk ack_seq=9bbc894565aa2f9a subflow ack_seq=9bbc894565aa2f9a [ 185.651496] MPTCP: msk=00000000c4b81cfc ssk=000000009743af53 data_avail=1 skb=0000000012e809e1 So this patch added these missing pr_fmt defines. Then we can get the same format string "MPTCP" in all mptcp logs like this: [ 142.795829] MPTCP: DSS [ 142.795829] MPTCP: data_fin=0 dsn64=0 use_map=0 ack64=1 use_ack=1 [ 142.795829] MPTCP: data_ack=8089704603109242421 [ 142.795830] MPTCP: msk=00000000133a24e0 ssk=000000002e508c64 data_avail=0 skb=00000000d5f230df [ 142.795830] MPTCP: msk=00000000133a24e0 ssk=000000002e508c64 status=0 [ 142.795831] MPTCP: msk ack_seq=66790290f1199d9b subflow ack_seq=66790290f1199d9b [ 142.795831] MPTCP: msk=00000000133a24e0 ssk=000000002e508c64 data_avail=1 skb=00000000de5aca2e Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts Signed-off-by: David S. Miller

mptcp: fix "fn parameter not described" warnings

2020-04-02T13:59:21Z

Obtained with: $ make W=1 net/mptcp/token.o net/mptcp/token.c:53: warning: Function parameter or member 'req' not described in 'mptcp_token_new_request' net/mptcp/token.c:98: warning: Function parameter or member 'sk' not described in 'mptcp_token_new_connect' net/mptcp/token.c:133: warning: Function parameter or member 'conn' not described in 'mptcp_token_new_accept' net/mptcp/token.c:178: warning: Function parameter or member 'token' not described in 'mptcp_token_destroy_request' net/mptcp/token.c:191: warning: Function parameter or member 'token' not described in 'mptcp_token_destroy' Fixes: 79c0949e9a09 (mptcp: Add key generation and token tree) Fixes: 58b09919626b (mptcp: create msk early) Signed-off-by: Matthieu Baerts Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

mptcp: re-check dsn before reading from subflow

2020-04-02T13:59:21Z

mptcp_subflow_data_available() is commonly called via ssk->sk_data_ready(), in this case the mptcp socket lock cannot be acquired. Therefore, while we can safely discard subflow data that was already received up to msk->ack_seq, we cannot be sure that 'subflow->data_avail' will still be valid at the time userspace wants to read the data -- a previous read on a different subflow might have carried this data already. In that (unlikely) event, msk->ack_seq will have been updated and will be ahead of the subflow dsn. We can check for this condition and skip/resync to the expected sequence number. Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

mptcp: subflow: check parent mptcp socket on subflow state change

2020-04-02T13:59:21Z

This is needed at least until proper MPTCP-Level fin/reset signalling gets added: We wake parent when a subflow changes, but we should do this only when all subflows have closed, not just one. Schedule the mptcp worker and tell it to check eof state on all subflows. Only flag mptcp socket as closed and wake userspace processes blocking in poll if all subflows have closed. Co-developed-by: Paolo Abeni Signed-off-by: Paolo Abeni Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

mptcp: fix tcp fallback crash

2020-04-02T13:59:21Z

Christoph Paasch reports following crash: general protection fault [..] CPU: 0 PID: 2874 Comm: syz-executor072 Not tainted 5.6.0-rc5 #62 RIP: 0010:__pv_queued_spin_lock_slowpath kernel/locking/qspinlock.c:471 [..] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:50 [inline] do_raw_spin_lock include/linux/spinlock.h:181 [inline] spin_lock_bh include/linux/spinlock.h:343 [inline] __mptcp_flush_join_list+0x44/0xb0 net/mptcp/protocol.c:278 mptcp_shutdown+0xb3/0x230 net/mptcp/protocol.c:1882 [..] Problem is that mptcp_shutdown() socket isn't an mptcp socket, its a plain tcp_sk. Thus, trying to access mptcp_sk specific members accesses garbage. Root cause is that accept() returns a fallback (tcp) socket, not an mptcp one. There is code in getpeername to detect this and override the sockets stream_ops. But this will only run when accept() caller provided a sockaddr struct. "accept(fd, NULL, 0)" will therefore result in mptcp stream ops, but with sock->sk pointing at a tcp_sk. Update the existing fallback handling to detect this as well. Moreover, mptcp_shutdown did not have fallback handling, and mptcp_poll did it too late so add that there as well. Reported-by: Christoph Paasch Tested-by: Christoph Paasch Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

mptcp: add netlink-based PM

2020-03-30T05:14:49Z

Expose a new netlink family to userspace to control the PM, setting: - list of local addresses to be signalled. - list of local addresses used to created subflows. - maximum number of add_addr option to react When the msk is fully established, the PM netlink attempts to announce the 'signal' list via the ADD_ADDR option. Since we currently lack the ADD_ADDR echo (and related event) only the first addr is sent. After exhausting the 'announce' list, the PM tries to create subflow for each addr in 'local' list, waiting for each connection to be completed before attempting the next one. Idea is to add an additional PM hook for ADD_ADDR echo, to allow the PM netlink announcing multiple addresses, in sequence. Co-developed-by: Matthieu Baerts Signed-off-by: Matthieu Baerts Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

mptcp: add and use MIB counter infrastructure

2020-03-30T05:14:49Z

Exported via same /proc file as the Linux TCP MIB counters, so "netstat -s" or "nstat" will show them automatically. The MPTCP MIB counters are allocated in a distinct pcpu area in order to avoid bloating/wasting TCP pcpu memory. Counters are allocated once the first MPTCP socket is created in a network namespace and free'd on exit. If no sockets have been allocated, all-zero mptcp counters are shown. The MIB counter list is taken from the multipath-tcp.org kernel, but only a few counters have been picked up so far. The counter list can be increased at any time later on. v2 -> v3: - remove 'inline' in foo.c files (David S. Miller) Co-developed-by: Paolo Abeni Signed-off-by: Paolo Abeni Signed-off-by: Florian Westphal Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

mptcp: allow dumping subflow context to userspace

2020-03-30T05:14:48Z

add ulp-specific diagnostic functions, so that subflow information can be dumped to userspace programs like 'ss'. v2 -> v3: - uapi: use bit macros appropriate for userspace Co-developed-by: Matthieu Baerts Signed-off-by: Matthieu Baerts Co-developed-by: Paolo Abeni Signed-off-by: Paolo Abeni Signed-off-by: Davide Caratti Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

mptcp: implement and use MPTCP-level retransmission

2020-03-30T05:14:48Z

On timeout event, schedule a work queue to do the retransmission. Retransmission code closely resembles the sendmsg() implementation and re-uses mptcp_sendmsg_frag, providing a dummy msghdr - for flags' sake - and peeking the relevant dfrag from the rtx head. Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller