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 9236921C163 for ; Thu, 15 May 2025 16:23:57 +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=1747326237; cv=none; b=dqsSMcK0e374AD0TRzwMr9E86uhB6l8T1OqO2Ej2a7BX1J6AjDJTglTSZQkBz4L7MiuS4AuXI3hYeZsET/bOgxsWOhykq/d/xSPeoLIm4WZcxWbqH5wv2/TYMphe7w3g+hUHV3g/UxBBJDdvGt4MkGpQob3Aph/bHj6MEo66CQE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747326237; c=relaxed/simple; bh=P/WbrkCCWVAE67Eh/Edw8zOyHyBqnFPHLIgu+5SOi/8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XaoamvJUVzNom2ovF6opsWLaOIYOY+/tDwAiZqSkXKgwNPib953PEiYGw9s9rG8K04lsQjPdCkQ1OPnD1/3eKeYn3pDtfiewVG7p/4ifaYL4Wt2y02NlwusIk3vwNQG6SkWWxZCFqp+kicAp89hOYcsleqdBopqI2me05aH/OMg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SG/poNuB; 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="SG/poNuB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3AD0C4CEEB; Thu, 15 May 2025 16:23:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747326237; bh=P/WbrkCCWVAE67Eh/Edw8zOyHyBqnFPHLIgu+5SOi/8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SG/poNuBDRSR9c/hGjz0soc4cTDemX6yAFxnvfcUlAO24AsEYUpHWc+l/JHnHGSxS wWVDSxiAa6xM9tKMlEgG0PtBjB5PHR2uSX1ZD0hWiWNdXZafBfwfHfFWFFS4vKtCTh EYXB288TdXpSxkFcvm5VCRXO5OPhOYoZloden3bh3ZneTU1CTWNLY9bsmxDfA8Jn5t 05v6l9taqBQ+TrqgmHqRRtvTg7kfOtW8c20kBW3YyWh0rwnEPnvSMFV6ym8F3DVdx+ eg0qvE+MziqNRxE65aUaYxv5znhUYavftHuHa3AOiD13phSO3ADN6/5sweQ1770iBp FDn/qke3NwelA== From: Mario Limonciello To: Shyam Sundar S K , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Cc: Hans de Goede , platform-driver-x86@vger.kernel.org (open list:AMD PMF DRIVER), Mario Limonciello Subject: [PATCH v4 1/3] platform/x86/amd: pmf: Use device managed allocations Date: Thu, 15 May 2025 11:23:49 -0500 Message-ID: <20250515162351.2111468-2-superm1@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250515162351.2111468-1-superm1@kernel.org> References: <20250515162351.2111468-1-superm1@kernel.org> Precedence: bulk X-Mailing-List: platform-driver-x86@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Mario Limonciello If setting up smart PC fails for any reason then this can lead to a double free when unloading amd-pmf. This is because dev->buf was freed but never set to NULL and is again freed in amd_pmf_remove(). To avoid subtle allocation bugs in failures leading to a double free change all allocations into device managed allocations. Fixes: 5b1122fc4995f ("platform/x86/amd/pmf: fix cleanup in amd_pmf_init_smart_pc()") Link: https://lore.kernel.org/r/20250512211154.2510397-2-superm1@kernel.org Signed-off-by: Mario Limonciello --- v4: * Handle failures from memory allocation on sideload (Ilpo) * Allocate memory before copying from user (Ilpo) --- drivers/platform/x86/amd/pmf/core.c | 3 +- drivers/platform/x86/amd/pmf/tee-if.c | 58 +++++++++------------------ 2 files changed, 20 insertions(+), 41 deletions(-) diff --git a/drivers/platform/x86/amd/pmf/core.c b/drivers/platform/x86/amd/pmf/core.c index 96821101ec773..395c011e837f1 100644 --- a/drivers/platform/x86/amd/pmf/core.c +++ b/drivers/platform/x86/amd/pmf/core.c @@ -280,7 +280,7 @@ int amd_pmf_set_dram_addr(struct amd_pmf_dev *dev, bool alloc_buffer) dev_err(dev->dev, "Invalid CPU id: 0x%x", dev->cpu_id); } - dev->buf = kzalloc(dev->mtable_size, GFP_KERNEL); + dev->buf = devm_kzalloc(dev->dev, dev->mtable_size, GFP_KERNEL); if (!dev->buf) return -ENOMEM; } @@ -493,7 +493,6 @@ static void amd_pmf_remove(struct platform_device *pdev) mutex_destroy(&dev->lock); mutex_destroy(&dev->update_mutex); mutex_destroy(&dev->cb_mutex); - kfree(dev->buf); } static const struct attribute_group *amd_pmf_driver_groups[] = { diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c index d3bd12ad036ae..6d85601812225 100644 --- a/drivers/platform/x86/amd/pmf/tee-if.c +++ b/drivers/platform/x86/amd/pmf/tee-if.c @@ -350,38 +350,30 @@ static ssize_t amd_pmf_get_pb_data(struct file *filp, const char __user *buf, size_t length, loff_t *pos) { struct amd_pmf_dev *dev = filp->private_data; - unsigned char *new_policy_buf; int ret; /* Policy binary size cannot exceed POLICY_BUF_MAX_SZ */ if (length > POLICY_BUF_MAX_SZ || length == 0) return -EINVAL; - /* re-alloc to the new buffer length of the policy binary */ - new_policy_buf = memdup_user(buf, length); - if (IS_ERR(new_policy_buf)) - return PTR_ERR(new_policy_buf); - - kfree(dev->policy_buf); - dev->policy_buf = new_policy_buf; + devm_kfree(dev->dev, dev->policy_buf); + dev->policy_buf = devm_kzalloc(dev->dev, length, GFP_KERNEL); + if (IS_ERR(dev->policy_buf)) + return -ENOMEM; dev->policy_sz = length; - if (!amd_pmf_pb_valid(dev)) { - ret = -EINVAL; - goto cleanup; - } + if (copy_from_user(dev->policy_buf, buf, length)) + return -EFAULT; + + if (!amd_pmf_pb_valid(dev)) + return -EINVAL; amd_pmf_hex_dump_pb(dev); ret = amd_pmf_start_policy_engine(dev); if (ret < 0) - goto cleanup; + return ret; return length; - -cleanup: - kfree(dev->policy_buf); - dev->policy_buf = NULL; - return ret; } static const struct file_operations pb_fops = { @@ -532,13 +524,13 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev) dev->policy_base = devm_ioremap_resource(dev->dev, dev->res); if (IS_ERR(dev->policy_base)) { ret = PTR_ERR(dev->policy_base); - goto err_free_dram_buf; + goto err_cancel_work; } - dev->policy_buf = kzalloc(dev->policy_sz, GFP_KERNEL); + dev->policy_buf = devm_kzalloc(dev->dev, dev->policy_sz, GFP_KERNEL); if (!dev->policy_buf) { ret = -ENOMEM; - goto err_free_dram_buf; + goto err_cancel_work; } memcpy_fromio(dev->policy_buf, dev->policy_base, dev->policy_sz); @@ -546,21 +538,21 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev) if (!amd_pmf_pb_valid(dev)) { dev_info(dev->dev, "No Smart PC policy present\n"); ret = -EINVAL; - goto err_free_policy; + goto err_cancel_work; } amd_pmf_hex_dump_pb(dev); - dev->prev_data = kzalloc(sizeof(*dev->prev_data), GFP_KERNEL); + dev->prev_data = devm_kzalloc(dev->dev, sizeof(*dev->prev_data), GFP_KERNEL); if (!dev->prev_data) { ret = -ENOMEM; - goto err_free_policy; + goto err_cancel_work; } for (i = 0; i < ARRAY_SIZE(amd_pmf_ta_uuid); i++) { ret = amd_pmf_tee_init(dev, &amd_pmf_ta_uuid[i]); if (ret) - goto err_free_prev_data; + goto err_cancel_work; ret = amd_pmf_start_policy_engine(dev); switch (ret) { @@ -575,7 +567,7 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev) default: ret = -EINVAL; amd_pmf_tee_deinit(dev); - goto err_free_prev_data; + goto err_cancel_work; } if (status) @@ -584,7 +576,7 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev) if (!status && !pb_side_load) { ret = -EINVAL; - goto err_free_prev_data; + goto err_cancel_work; } if (pb_side_load) @@ -600,12 +592,6 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev) if (pb_side_load && dev->esbin) amd_pmf_remove_pb(dev); amd_pmf_tee_deinit(dev); -err_free_prev_data: - kfree(dev->prev_data); -err_free_policy: - kfree(dev->policy_buf); -err_free_dram_buf: - kfree(dev->buf); err_cancel_work: cancel_delayed_work_sync(&dev->pb_work); @@ -621,11 +607,5 @@ void amd_pmf_deinit_smart_pc(struct amd_pmf_dev *dev) amd_pmf_remove_pb(dev); cancel_delayed_work_sync(&dev->pb_work); - kfree(dev->prev_data); - dev->prev_data = NULL; - kfree(dev->policy_buf); - dev->policy_buf = NULL; - kfree(dev->buf); - dev->buf = NULL; amd_pmf_tee_deinit(dev); } -- 2.43.0