From 27b0e701d3872ba59c5b579a9e8a02ea49ad3d3b Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Tue, 28 Oct 2025 09:16:52 +0100 Subject: mptcp: drop bogus optimization in __mptcp_check_push() Accessing the transmit queue without owning the msk socket lock is inherently racy, hence __mptcp_check_push() could actually quit early even when there is pending data. That in turn could cause unexpected tx lock and timeout. Dropping the early check avoids the race, implicitly relaying on later tests under the relevant lock. With such change, all the other mptcp_send_head() call sites are now under the msk socket lock and we can additionally drop the now unneeded annotation on the transmit head pointer accesses. Fixes: 6e628cd3a8f7 ("mptcp: use mptcp release_cb for delayed tasks") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni Reviewed-by: Geliang Tang Tested-by: Geliang Tang Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20251028-net-mptcp-send-timeout-v1-1-38ffff5a9ec8@kernel.org Signed-off-by: Jakub Kicinski --- net/mptcp/protocol.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/mptcp/protocol.h') diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 52f9cfa4ce95..379a88e14e8d 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -414,7 +414,7 @@ static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) { const struct mptcp_sock *msk = mptcp_sk(sk); - return READ_ONCE(msk->first_pending); + return msk->first_pending; } static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) -- cgit v1.2.3