diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2021-06-22 03:33:08 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-06-22 20:22:42 +0300 |
| commit | 490274b47468793e3e157c2df6b2da0e646cc4a9 (patch) | |
| tree | b9e59a12ecd1f2169d00e68b1789910b3c42c8b3 /net/mptcp/protocol.c | |
| parent | 3ddd6e2f71092766b6040b9c33cf9906577b4025 (diff) | |
| download | linux-490274b47468793e3e157c2df6b2da0e646cc4a9.tar.xz | |
mptcp: avoid race on msk state changes
The msk socket state is currently updated in a few spots without
owning the msk socket lock itself.
Some of such operations are safe, as they happens before exposing
the msk socket to user-space and can't race with other changes.
A couple of them, at connect time, can actually race with close()
or shutdown(), leaving breaking the socket state machine.
This change addresses the issue moving such update under the msk
socket lock with the usual:
<acquire spinlock>
<check sk lock onwers>
<ev defer to release_cb>
scheme.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/56
Fixes: 8fd738049ac3 ("mptcp: fallback in case of simultaneous connect")
Fixes: c3c123d16c0e ("net: mptcp: don't hang in mptcp_sendmsg() after TCP fallback")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mptcp/protocol.c')
| -rw-r--r-- | net/mptcp/protocol.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 632350018fb6..8ead550df8b1 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2946,6 +2946,11 @@ static void mptcp_release_cb(struct sock *sk) spin_lock_bh(&sk->sk_lock.slock); } + /* be sure to set the current sk state before tacking actions + * depending on sk_state + */ + if (test_and_clear_bit(MPTCP_CONNECTED, &mptcp_sk(sk)->flags)) + __mptcp_set_connected(sk); if (test_and_clear_bit(MPTCP_CLEAN_UNA, &mptcp_sk(sk)->flags)) __mptcp_clean_una_wakeup(sk); if (test_and_clear_bit(MPTCP_ERROR_REPORT, &mptcp_sk(sk)->flags)) |