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 0337715CAE for ; Tue, 8 Nov 2022 14:10:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D7D8C433D6; Tue, 8 Nov 2022 14:10:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1667916655; bh=vKsjsUd37Zi36AVnvxrSGEcd04fPDqeHOW1Qn+w+h8s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IE3Mbzaby4qdjb49oYy5fP98th8ZVjlzulpnNi4WbpHULLHO6R3p7NpLcLdySrvPh ioqfZupEsojDLCFmmIpMKXAiXgkwxWYZUZ+eO7obN88TSr29iqiEzRnOPwJ+Cc76O8 Sz838pzcd6Nr262DOdwvZSnDWAxNTNxtMF5tZ+rk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dexuan Cui , Stefano Garzarella , =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20Dalleau?= , Paolo Abeni , Sasha Levin Subject: [PATCH 6.0 062/197] vsock: fix possible infinite sleep in vsock_connectible_wait_data() Date: Tue, 8 Nov 2022 14:38:20 +0100 Message-Id: <20221108133357.659437140@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221108133354.787209461@linuxfoundation.org> References: <20221108133354.787209461@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Dexuan Cui [ Upstream commit 466a85336fee6e3b35eb97b8405a28302fd25809 ] Currently vsock_connectible_has_data() may miss a wakeup operation between vsock_connectible_has_data() == 0 and the prepare_to_wait(). Fix the race by adding the process to the wait queue before checking vsock_connectible_has_data(). Fixes: b3f7fd54881b ("af_vsock: separate wait data loop") Signed-off-by: Dexuan Cui Reviewed-by: Stefano Garzarella Reported-by: Frédéric Dalleau Tested-by: Frédéric Dalleau Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/vmw_vsock/af_vsock.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index b4ee163154a6..e5ab2418f9d6 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1894,8 +1894,11 @@ static int vsock_connectible_wait_data(struct sock *sk, err = 0; transport = vsk->transport; - while ((data = vsock_connectible_has_data(vsk)) == 0) { + while (1) { prepare_to_wait(sk_sleep(sk), wait, TASK_INTERRUPTIBLE); + data = vsock_connectible_has_data(vsk); + if (data != 0) + break; if (sk->sk_err != 0 || (sk->sk_shutdown & RCV_SHUTDOWN) || -- 2.35.1