diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2022-06-28 04:02:38 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-06-29 06:45:42 +0300 |
| commit | d51991e2e31477853e5b9c1005ac617707077286 (patch) | |
| tree | b49c6d4c82eaf1dff520fecdd3caa84f60718956 /net/mptcp/protocol.h | |
| parent | 76a13b315709b5b65a7b65caf9ede9a8a38d8930 (diff) | |
| download | linux-d51991e2e31477853e5b9c1005ac617707077286.tar.xz | |
mptcp: fix shutdown vs fallback race
If the MPTCP socket shutdown happens before a fallback
to TCP, and all the pending data have been already spooled,
we never close the TCP connection.
Address the issue explicitly checking for critical condition
at fallback time.
Fixes: 1e39e5a32ad7 ("mptcp: infinite mapping sending")
Fixes: 0348c690ed37 ("mptcp: add the fallback check")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/protocol.h')
| -rw-r--r-- | net/mptcp/protocol.h | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 1d2d71711872..9860179bfd5e 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -927,12 +927,25 @@ static inline void __mptcp_do_fallback(struct mptcp_sock *msk) set_bit(MPTCP_FALLBACK_DONE, &msk->flags); } -static inline void mptcp_do_fallback(struct sock *sk) +static inline void mptcp_do_fallback(struct sock *ssk) { - struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); - struct mptcp_sock *msk = mptcp_sk(subflow->conn); + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); + struct sock *sk = subflow->conn; + struct mptcp_sock *msk; + msk = mptcp_sk(sk); __mptcp_do_fallback(msk); + if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { + gfp_t saved_allocation = ssk->sk_allocation; + + /* we are in a atomic (BH) scope, override ssk default for data + * fin allocation + */ + ssk->sk_allocation = GFP_ATOMIC; + ssk->sk_shutdown |= SEND_SHUTDOWN; + tcp_shutdown(ssk, SEND_SHUTDOWN); + ssk->sk_allocation = saved_allocation; + } } #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) |