diff mbox series

[net,3/7] mptcp: fix more tx path fields initialization

Message ID 20240208-upstream-net-20240202-locking-cleanup-misc-v1-3-f75cc5b97e5a@kernel.org (mailing list archive)
State Accepted
Commit 3f83d8a77eeeb47011b990fd766a421ee64f1d73
Delegated to: Netdev Maintainers
Headers show
Series mptcp: locking cleanup & misc. fixes | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1022 this patch: 1022
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: geliang.tang@linux.dev
netdev/build_clang success Errors and warnings before: 1037 this patch: 1037
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1039 this patch: 1039
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 35 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Matthieu Baerts Feb. 8, 2024, 6:03 p.m. UTC 
From: Paolo Abeni <pabeni@redhat.com>

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: 6d0060f600ad ("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>
---
 net/mptcp/protocol.c |  6 ++----
 net/mptcp/subflow.c  | 13 +++++++++++--
 2 files changed, 13 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 7632eafb683b..8cb6a873dae9 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -3478,10 +3478,8 @@  void mptcp_finish_connect(struct sock *ssk)
 	 * accessing the field below
 	 */
 	WRITE_ONCE(msk->local_key, subflow->local_key);
-	WRITE_ONCE(msk->write_seq, subflow->idsn + 1);
-	WRITE_ONCE(msk->snd_nxt, msk->write_seq);
-	WRITE_ONCE(msk->snd_una, msk->write_seq);
-	WRITE_ONCE(msk->wnd_end, msk->snd_nxt + tcp_sk(ssk)->snd_wnd);
+	WRITE_ONCE(msk->snd_una, subflow->idsn + 1);
+	WRITE_ONCE(msk->wnd_end, subflow->idsn + 1 + tcp_sk(ssk)->snd_wnd);
 
 	mptcp_pm_new_connection(msk, ssk, 0);
 }
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 56b2ac2f2f22..c2df34ebcf28 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -421,12 +421,21 @@  static bool subflow_use_different_dport(struct mptcp_sock *msk, const struct soc
 
 void __mptcp_sync_state(struct sock *sk, int state)
 {
+	struct mptcp_subflow_context *subflow;
 	struct mptcp_sock *msk = mptcp_sk(sk);
+	struct sock *ssk = msk->first;
 
-	__mptcp_propagate_sndbuf(sk, msk->first);
+	subflow = mptcp_subflow_ctx(ssk);
+	__mptcp_propagate_sndbuf(sk, ssk);
 	if (!msk->rcvspace_init)
-		mptcp_rcv_space_init(msk, msk->first);
+		mptcp_rcv_space_init(msk, ssk);
+
 	if (sk->sk_state == TCP_SYN_SENT) {
+		/* subflow->idsn is always available is TCP_SYN_SENT state,
+		 * even for the FASTOPEN scenarios
+		 */
+		WRITE_ONCE(msk->write_seq, subflow->idsn + 1);
+		WRITE_ONCE(msk->snd_nxt, msk->write_seq);
 		mptcp_set_state(sk, state);
 		sk->sk_state_change(sk);
 	}