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 1420A1607B7; Wed, 5 Feb 2025 14:48:37 +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=1738766918; cv=none; b=sunFTCG2aWVT3dCVFp4wBawsO/B9hDnrCHg+uWpKqrZiH0nFtTXaV9eAIU9Z2reBVLHAvwQDEoLlaJai4kxDPSZ50mck958ac+bris3scdigQfKLbWy4HJGxJl4MvxxzSshHEmzPZDPyeBMMVJDFLoiBvVQc4g0LvD6nUx8XgZI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738766918; c=relaxed/simple; bh=YhnwSAXvrhR4Ahx5LDljKueXJi20F48MxufImqqZYrw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DSPhdzpy+2aYEJSJ2Jwy2JNBKTtVfPAuj68CKOxxfBPtVCi4JwQ1NcOa7GnNa+zw+9Mxd47RAhMDiIINkNhMP03DyYXuO4kx9FEq64aH8S51BRumq1EqDw0b0sFgPTLl2/ZQVuJcZSxTog3MUGIKJHJ0Ylqmws+uSZq5O5ZHfUA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oRFpL7rr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="oRFpL7rr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B3FDC4CED1; Wed, 5 Feb 2025 14:48:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1738766917; bh=YhnwSAXvrhR4Ahx5LDljKueXJi20F48MxufImqqZYrw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oRFpL7rrjjsjUIgozqbN7ibFKjYFNkRKapImPtV1QVu+pgxAe8IWLgh4OtTCNdt+I BrSoL1UoxJNyiFSLbGF0Tzlid7TVhpFmWzBlR0uakHtfAwakULsaoQLUE44X1nYw7F yLskKqRLqCzSmtg2uKZSAgPbjJT7MXuKVcp9rcCE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Krzysztof Kozlowski , Bjorn Andersson , Sasha Levin Subject: [PATCH 6.12 380/590] firmware: qcom: scm: Cleanup global __scm on probe failures Date: Wed, 5 Feb 2025 14:42:15 +0100 Message-ID: <20250205134509.807833036@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250205134455.220373560@linuxfoundation.org> References: <20250205134455.220373560@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Krzysztof Kozlowski [ Upstream commit 1e76b546e6fca7eb568161f408133904ca6bcf4f ] If SCM driver fails the probe, it should not leave global '__scm' variable assigned, because external users of this driver will assume the probe finished successfully. For example TZMEM parts ('__scm->mempool') are initialized later in the probe, but users of it (__scm_smc_call()) rely on the '__scm' variable. This fixes theoretical NULL pointer exception, triggered via introducing probe deferral in SCM driver with call trace: qcom_tzmem_alloc+0x70/0x1ac (P) qcom_tzmem_alloc+0x64/0x1ac (L) qcom_scm_assign_mem+0x78/0x194 qcom_rmtfs_mem_probe+0x2d4/0x38c platform_probe+0x68/0xc8 Fixes: 40289e35ca52 ("firmware: qcom: scm: enable the TZ mem allocator") Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20241209-qcom-scm-missing-barriers-and-all-sort-of-srap-v2-4-9061013c8d92@linaro.org Signed-off-by: Bjorn Andersson Signed-off-by: Sasha Levin --- drivers/firmware/qcom/qcom_scm.c | 42 ++++++++++++++++++++++---------- 1 file changed, 29 insertions(+), 13 deletions(-) diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c index 14afd68664a91..a6bdedbbf7088 100644 --- a/drivers/firmware/qcom/qcom_scm.c +++ b/drivers/firmware/qcom/qcom_scm.c @@ -2001,13 +2001,17 @@ static int qcom_scm_probe(struct platform_device *pdev) irq = platform_get_irq_optional(pdev, 0); if (irq < 0) { - if (irq != -ENXIO) - return irq; + if (irq != -ENXIO) { + ret = irq; + goto err; + } } else { ret = devm_request_threaded_irq(__scm->dev, irq, NULL, qcom_scm_irq_handler, IRQF_ONESHOT, "qcom-scm", __scm); - if (ret < 0) - return dev_err_probe(scm->dev, ret, "Failed to request qcom-scm irq\n"); + if (ret < 0) { + dev_err_probe(scm->dev, ret, "Failed to request qcom-scm irq\n"); + goto err; + } } __get_convention(); @@ -2026,14 +2030,18 @@ static int qcom_scm_probe(struct platform_device *pdev) qcom_scm_disable_sdi(); ret = of_reserved_mem_device_init(__scm->dev); - if (ret && ret != -ENODEV) - return dev_err_probe(__scm->dev, ret, - "Failed to setup the reserved memory region for TZ mem\n"); + if (ret && ret != -ENODEV) { + dev_err_probe(__scm->dev, ret, + "Failed to setup the reserved memory region for TZ mem\n"); + goto err; + } ret = qcom_tzmem_enable(__scm->dev); - if (ret) - return dev_err_probe(__scm->dev, ret, - "Failed to enable the TrustZone memory allocator\n"); + if (ret) { + dev_err_probe(__scm->dev, ret, + "Failed to enable the TrustZone memory allocator\n"); + goto err; + } memset(&pool_config, 0, sizeof(pool_config)); pool_config.initial_size = 0; @@ -2041,9 +2049,11 @@ static int qcom_scm_probe(struct platform_device *pdev) pool_config.max_size = SZ_256K; __scm->mempool = devm_qcom_tzmem_pool_new(__scm->dev, &pool_config); - if (IS_ERR(__scm->mempool)) - return dev_err_probe(__scm->dev, PTR_ERR(__scm->mempool), - "Failed to create the SCM memory pool\n"); + if (IS_ERR(__scm->mempool)) { + dev_err_probe(__scm->dev, PTR_ERR(__scm->mempool), + "Failed to create the SCM memory pool\n"); + goto err; + } /* * Initialize the QSEECOM interface. @@ -2059,6 +2069,12 @@ static int qcom_scm_probe(struct platform_device *pdev) WARN(ret < 0, "failed to initialize qseecom: %d\n", ret); return 0; + +err: + /* Paired with smp_load_acquire() in qcom_scm_is_available(). */ + smp_store_release(&__scm, NULL); + + return ret; } static void qcom_scm_shutdown(struct platform_device *pdev) -- 2.39.5