diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2025-11-18 08:20:22 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-11-19 20:07:14 -0800 |
| commit | 1bba3f219c5e8c29e63afa3c1fc24f875ebec119 (patch) | |
| tree | 2a3becab02189c5b49fea5ce0b713694b209be95 /net/mptcp/protocol.c | |
| parent | 17393fa7b7086664be519e7230cb6ed7ec7d9462 (diff) | |
mptcp: do not fallback when OoO is present
In case of DSS corruption, the MPTCP protocol tries to avoid the subflow
reset if fallback is possible. Such corruptions happen in the receive
path; to ensure fallback is possible the stack additionally needs to
check for OoO data, otherwise the fallback will break the data stream.
Fixes: e32d262c89e2 ("mptcp: handle consistently DSS corruption")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/598
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20251118-net-mptcp-misc-fixes-6-18-rc6-v1-4-806d3781c95f@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/protocol.c')
| -rw-r--r-- | net/mptcp/protocol.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index e30e9043a694..6f0e8f670d83 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -76,6 +76,13 @@ bool __mptcp_try_fallback(struct mptcp_sock *msk, int fb_mib) if (__mptcp_check_fallback(msk)) return true; + /* The caller possibly is not holding the msk socket lock, but + * in the fallback case only the current subflow is touching + * the OoO queue. + */ + if (!RB_EMPTY_ROOT(&msk->out_of_order_queue)) + return false; + spin_lock_bh(&msk->fallback_lock); if (!msk->allow_infinite_fallback) { spin_unlock_bh(&msk->fallback_lock); |