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 947B126462A; Mon, 3 Mar 2025 16:31:49 +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=1741019509; cv=none; b=bEOOdszjsVke0kQ9r6MBtakcGKKXmvv518BvkrQjXsmvohdqE8v2hdboWoMjKdPyH5cS9JCbF3QkyeL6azkhn7IuurssukBLb8Nrv9qt9nsxPeL5RNsV8o2VXPMhE/ITdW2wAo5WE/3lRe42sS1ktsz8gyR8nAkZ80txJcVfcq8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741019509; c=relaxed/simple; bh=w4eZ7vTmYbfaw63YjKeyHVuq0kQ1D/IJR+agJq/71Rg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=jsU550NucV9RXSh9SP4qQ7Qa4wKHa3jvsrqmMqHmsBk9zevMHYQjLhv2R+pIIk7Sbb60n0Pi4IECN5NVMA7Bs89Tx3TE23tmfKZUwjb18S5745EjI2xMLUpbFeyP6FR5jdzCLpdX/jfjwPtmF7kIqmkOMy1vgdfULSO29WSeOwQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bOOTHEdQ; 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="bOOTHEdQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D10D6C4CED6; Mon, 3 Mar 2025 16:31:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741019509; bh=w4eZ7vTmYbfaw63YjKeyHVuq0kQ1D/IJR+agJq/71Rg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bOOTHEdQ/J1vC/HxPIQIGz7elaYHIWEVZf1N3G/qHjgKyceXusXpi1M4t5+PRoEMb 7Qr0ZvuVFWceKXmR/z9WjIPsasJ/JeTMw3Co6c2bENruGdBHJSXYtI7t6zW7kMYFxg GKNnNcI/inZvWBXk+w3SBBKEGy+BdfUKO64VMJrig0c4dP2ko2dzgHAlyVIrei7kMt jgM4Ct7hBsGLunE2CavWY9xnSNqfYeSNJMiToTsva2T5A/lHgrVyZ/dU8I2iYpI8Gj ChTaaK5CpT9ofp8PcXIw4ZiTReoLWRHpH2H74P9VQQsXBT0Y32RowEpIcRaqVnEKaS Ey9cxcDA2STCQ== 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 6.1 7/9] mptcp: safety check before fallback Date: Mon, 3 Mar 2025 11:31:31 -0500 Message-Id: <20250303163133.3764032-7-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250303163133.3764032-1-sashal@kernel.org> References: <20250303163133.3764032-1-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 6.1.129 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 77e727d81cc24..25c1cda5c1bcf 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -981,6 +981,8 @@ 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