From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F8562517BB; Mon, 3 Mar 2025 16:31:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741019460; cv=none; b=eCoWnhHGtztR0vONvUYH0REEhW0t0bO04bI+L+T6lGZ9+9uzq0zKTqCIG6rmDh5EAtYJP3rTTXcXmL/HzT/dJqZqBAthswlzm5rkLPj2sWg+6q4UkFtnovy532Az4/ti0jho1/seXXzXrddtjod/D1mdCs22nuIZpltCxxnprZ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741019460; c=relaxed/simple; bh=PQcdHR7xGldchHufFfkG93+0uiY9+gpl16eM5PJNtzI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=LeSzln+dUipCNQGKesr3tXGHN2EMT+TJve+gDxoT8DZnbKkT/M9q8phKk8Q3w4I70lUBu1Mb6dPDtTaIGkljz1T58nOtwC3puAIB9uFEmts+5tc6NNA2P7rOAe2wFebuYOJs+uF9qOhtN+i1OW+bH8MMVaedv/eAnq2T2emhd9w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ErdBMfGe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ErdBMfGe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85AFAC4CEE6; Mon, 3 Mar 2025 16:30:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741019459; bh=PQcdHR7xGldchHufFfkG93+0uiY9+gpl16eM5PJNtzI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ErdBMfGe6mc0CmdOLIjWyZLb5U4S8HrTqG1dPdajp+fggUf207buPakKaIccgU2ps 6c1v6UePJOsO2u4dT/pyl9nLN77/o+yJTEhL6lqq26sJ0A+c5D3/KclnriQ91nzWn2 kFJbz1llYfOlSr1EnEzC11CMZYUNFxajeyT1XmdBIREfddSGCBFCuFaBKFa+0ENWY/ XIyAhfFY2t1K+0PIf1dZNcaBcnZFXQW/jOBSvabY5wDivkb+VsVwkDY2rGiXOetr+y qAwLLDuNJYwV4opB1QcTSHRF0Fnh/7Xj9p9yBZ7dtSlZWHwyNhOYgJ2WTqdSxLl3JP FQxGKcUR9Pu9Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Matthieu Baerts (NGI0)" , Paolo Abeni , Jakub Kicinski , Sasha Levin , martineau@kernel.org, davem@davemloft.net, edumazet@google.com, netdev@vger.kernel.org, mptcp@lists.linux.dev Subject: [PATCH AUTOSEL 6.12 13/17] mptcp: safety check before fallback Date: Mon, 3 Mar 2025 11:30:25 -0500 Message-Id: <20250303163031.3763651-13-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250303163031.3763651-1-sashal@kernel.org> References: <20250303163031.3763651-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.17 Content-Transfer-Encoding: 8bit From: "Matthieu Baerts (NGI0)" [ Upstream commit db75a16813aabae3b78c06b1b99f5e314c1f55d3 ] Recently, some fallback have been initiated, while the connection was not supposed to fallback. Add a safety check with a warning to detect when an wrong attempt to fallback is being done. This should help detecting any future issues quicker. Acked-by: Paolo Abeni Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250224-net-mptcp-misc-fixes-v1-3-f550f636b435@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/mptcp/protocol.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index b70a303e08287..7e2f70f22b05b 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -1194,6 +1194,8 @@ static inline void __mptcp_do_fallback(struct mptcp_sock *msk) pr_debug("TCP fallback already done (msk=%p)\n", msk); return; } + if (WARN_ON_ONCE(!READ_ONCE(msk->allow_infinite_fallback))) + return; set_bit(MPTCP_FALLBACK_DONE, &msk->flags); } -- 2.39.5