summaryrefslogtreecommitdiff
path: root/net/mptcp
diff options
context:
space:
mode:
authorDavide Caratti <dcaratti@redhat.com>2020-03-11 21:50:53 +0300
committerDavid S. Miller <davem@davemloft.net>2020-03-12 09:59:11 +0300
commit767d3ded5fb88e95f137893a8d90d1738b897029 (patch)
tree48222f4ee3c6e81a75ba4d1530e3abcabcf2789f /net/mptcp
parentdc3e19f4572b2bf0c4dc4024fd7ae8c214815a1a (diff)
downloadlinux-767d3ded5fb88e95f137893a8d90d1738b897029.tar.xz
net: mptcp: don't hang before sending 'MP capable with data'
the following packetdrill script socket(..., SOCK_STREAM, IPPROTO_MPTCP) = 3 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR) fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress) > S 0:0(0) <mss 1460,sackOK,TS val 100 ecr 0,nop,wscale 8,mpcapable v1 flags[flag_h] nokey> < S. 0:0(0) ack 1 win 65535 <mss 1460,sackOK,TS val 700 ecr 100,nop,wscale 8,mpcapable v1 flags[flag_h] key[skey=2]> > . 1:1(0) ack 1 win 256 <nop, nop, TS val 100 ecr 700,mpcapable v1 flags[flag_h] key[ckey,skey]> getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0 fcntl(3, F_SETFL, O_RDWR) = 0 write(3, ..., 1000) = 1000 doesn't transmit 1KB data packet after a successful three-way-handshake, using mp_capable with data as required by protocol v1, and write() hangs forever: PID: 973 TASK: ffff97dd399cae80 CPU: 1 COMMAND: "packetdrill" #0 [ffffa9b94062fb78] __schedule at ffffffff9c90a000 #1 [ffffa9b94062fc08] schedule at ffffffff9c90a4a0 #2 [ffffa9b94062fc18] schedule_timeout at ffffffff9c90e00d #3 [ffffa9b94062fc90] wait_woken at ffffffff9c120184 #4 [ffffa9b94062fcb0] sk_stream_wait_connect at ffffffff9c75b064 #5 [ffffa9b94062fd20] mptcp_sendmsg at ffffffff9c8e801c #6 [ffffa9b94062fdc0] sock_sendmsg at ffffffff9c747324 #7 [ffffa9b94062fdd8] sock_write_iter at ffffffff9c7473c7 #8 [ffffa9b94062fe48] new_sync_write at ffffffff9c302976 #9 [ffffa9b94062fed0] vfs_write at ffffffff9c305685 #10 [ffffa9b94062ff00] ksys_write at ffffffff9c305985 #11 [ffffa9b94062ff38] do_syscall_64 at ffffffff9c004475 #12 [ffffa9b94062ff50] entry_SYSCALL_64_after_hwframe at ffffffff9ca0008c RIP: 00007f959407eaf7 RSP: 00007ffe9e95a910 RFLAGS: 00000293 RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f959407eaf7 RDX: 00000000000003e8 RSI: 0000000001785fe0 RDI: 0000000000000008 RBP: 0000000001785fe0 R8: 0000000000000000 R9: 0000000000000003 R10: 0000000000000007 R11: 0000000000000293 R12: 00000000000003e8 R13: 00007ffe9e95ae30 R14: 0000000000000000 R15: 0000000000000000 ORIG_RAX: 0000000000000001 CS: 0033 SS: 002b Fix it ensuring that socket state is TCP_ESTABLISHED on reception of the third ack. Fixes: 1954b86016cf ("mptcp: Check connection state before attempting send") Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mptcp')
-rw-r--r--net/mptcp/protocol.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 95007e433109..c0cef07f4382 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1049,6 +1049,10 @@ void mptcp_finish_connect(struct sock *ssk)
WRITE_ONCE(msk->write_seq, subflow->idsn + 1);
WRITE_ONCE(msk->ack_seq, ack_seq);
WRITE_ONCE(msk->can_ack, 1);
+ if (inet_sk_state_load(sk) != TCP_ESTABLISHED) {
+ inet_sk_state_store(sk, TCP_ESTABLISHED);
+ sk->sk_state_change(sk);
+ }
}
static void mptcp_sock_graft(struct sock *sk, struct socket *parent)