From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71CEEC433E0 for ; Fri, 12 Feb 2021 19:27:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1616664E05 for ; Fri, 12 Feb 2021 19:27:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231910AbhBLT1p (ORCPT ); Fri, 12 Feb 2021 14:27:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45276 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230053AbhBLT1l (ORCPT ); Fri, 12 Feb 2021 14:27:41 -0500 Received: from mail-lf1-x132.google.com (mail-lf1-x132.google.com [IPv6:2a00:1450:4864:20::132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E159C0613D6 for ; Fri, 12 Feb 2021 11:27:01 -0800 (PST) Received: by mail-lf1-x132.google.com with SMTP id m22so1053597lfg.5 for ; Fri, 12 Feb 2021 11:27:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=IP5QHmh/uMxvGIZstG4E6Zl93QlY3SkTHtuFh4ovGBk=; b=TasdBCqiOuiYWTRqMgX5qxBPZXpdf6fl7+gC1xYpA8jdRsBd0Yr+3iEDtYr6SQ+Z68 UznHFCytnWtegksCWO61y/C1bNY1nNCWlQaho/pTCmdY3RYDaHyAy0r7+Elz05soE+Z6 GsRnIVV2jiGYVR35CQ0ZUB7PAVkBG+DBk93xAGllgPqNyv9MNaOnS+iTMcZl+8hMkzwS 84peyD59+U9XDdg4hC9SLlE9YKvkFR5H6DBAt+cx/mn/CHB6X/jC/JFNYvLqJbQLsoG6 IJGEaCcALVFskmkEp5pg8/TD+SlC5zNuskFEp8E9MENIeVM/2OwYV9X9WvhJBJ7oEeX1 vWrA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=IP5QHmh/uMxvGIZstG4E6Zl93QlY3SkTHtuFh4ovGBk=; b=hCDen6nrOshTLiTUmJyyuGJIt8kCa5jz75q2M0dqLxBYJJ3AXHdPmSPD4QAoyAuIG3 jAxPwhcZHt+HBugAKzXImbHEWJXcZ9zv9/otbYtaUSglaWtFAVV/h0JqTd2jAVPgEM0p zXcQlyUtvA4wvAEbUjSXRReF0c07BPjW/Y2mPcTzxOCM5kYmqwuih15Tj0a49N1pECS+ frzgvriZINxybQARmmb0YBgGaALj/m/EhlvVYN6AyqvLd8UxXiCHq3HyAKsB9U0Wl64E h7oOgedvmkMWJSSZPfksgT7js0rh/5cbkRV7v6DHpMRiSNnrq9iCgYqQ0DP1FDGO5qPh mpVg== X-Gm-Message-State: AOAM531TS2asF/onmuf9fwzlbHwRWlDt42TALA6nhhmvzrloCK4wGE2o +Yk+3nwayIdTPDnkkCNpzh0VPQ== X-Google-Smtp-Source: ABdhPJxsfSkrWI3+yycb+PDvI7VGwKvvT+15WEsOznX+uhli7wFIgyrpO7My86tu+D5P5hyBSbe/GQ== X-Received: by 2002:a05:6512:39d5:: with SMTP id k21mr2277608lfu.142.1613158019847; Fri, 12 Feb 2021 11:26:59 -0800 (PST) Received: from eriador.lan ([37.153.55.125]) by smtp.gmail.com with ESMTPSA id b5sm1209133lfi.3.2021.02.12.11.26.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 Feb 2021 11:26:59 -0800 (PST) From: Dmitry Baryshkov To: Arnd Bergmann , Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, Srinivas Kandagatla , Jonathan Marek , stable@vger.kernel.org Subject: [PATCH v2] misc: fastrpc: restrict user apps from sending kernel RPC messages Date: Fri, 12 Feb 2021 22:26:58 +0300 Message-Id: <20210212192658.3476137-1-dmitry.baryshkov@linaro.org> X-Mailer: git-send-email 2.30.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Verify that user applications are not using the kernel RPC message handle to restrict them from directly attaching to guest OS on the remote subsystem. This is a port of CVE-2019-2308 fix. Fixes: c68cfb718c8f ("misc: fastrpc: Add support for context Invoke method") Cc: Srinivas Kandagatla Cc: Jonathan Marek Cc: stable@vger.kernel.org Signed-off-by: Dmitry Baryshkov --- Changes since v1: - changed to dev_warn_ratelimited to prevent userspace from flooding kernel log drivers/misc/fastrpc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index f12e909034ac..beda610e6b30 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -950,6 +950,11 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, if (!fl->cctx->rpdev) return -EPIPE; + if (handle == FASTRPC_INIT_HANDLE && !kernel) { + dev_warn_ratelimited(fl->sctx->dev, "user app trying to send a kernel RPC message (%d)\n", handle); + return -EPERM; + } + ctx = fastrpc_context_alloc(fl, kernel, sc, args); if (IS_ERR(ctx)) return PTR_ERR(ctx); -- 2.30.0