linux-kernel - [PATCH v2 2/2] platform/x86/amd/pmf: Fixup error handling for amd_pmf_init_smart

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Message-ID: <20240217014107.113749-3-mario.limonciello@amd.com>
Date: Fri, 16 Feb 2024 19:41:07 -0600
From: Mario Limonciello <mario.limonciello@....com>
To: <Shyam-sundar.S-k@....com>, <hdegoede@...hat.com>
CC: <platform-driver-x86@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	Mario Limonciello <mario.limonciello@....com>
Subject: [PATCH v2 2/2] platform/x86/amd/pmf: Fixup error handling for amd_pmf_init_smart_pc()

amd_pmf_init_smart_pc() calls out to amd_pmf_get_bios_buffer() but
the error handling flow doesn't clean everything up allocated
memory.

As amd_pmf_get_bios_buffer() is only called by amd_pmf_init_smart_pc(),
fold it into the function and add labels to clean up any step that
can fail along the way. Explicitly set everything allocated to NULL as
there are other features that may access some of the same variables.

Fixes: 7c45534afa44 ("platform/x86/amd/pmf: Add support for PMF Policy Binary")
Signed-off-by: Mario Limonciello <mario.limonciello@....com>
---
v1->v2:
 * Use a single label
 * Move all into amd_pmf_deinit_smart_pc()
 * Set to NULL explicitly
---
 drivers/platform/x86/amd/pmf/tee-if.c | 65 ++++++++++++++++-----------
 1 file changed, 40 insertions(+), 25 deletions(-)

diff --git a/drivers/platform/x86/amd/pmf/tee-if.c b/drivers/platform/x86/amd/pmf/tee-if.c
index 1359ab340f7c..4f74de680654 100644
--- a/drivers/platform/x86/amd/pmf/tee-if.c
+++ b/drivers/platform/x86/amd/pmf/tee-if.c
@@ -338,25 +338,6 @@ static void amd_pmf_remove_pb(struct amd_pmf_dev *dev) {}
 static void amd_pmf_hex_dump_pb(struct amd_pmf_dev *dev) {}
 #endif
 
-static int amd_pmf_get_bios_buffer(struct amd_pmf_dev *dev)
-{
-	dev->policy_buf = kzalloc(dev->policy_sz, GFP_KERNEL);
-	if (!dev->policy_buf)
-		return -ENOMEM;
-
-	dev->policy_base = devm_ioremap(dev->dev, dev->policy_addr, dev->policy_sz);
-	if (!dev->policy_base)
-		return -ENOMEM;
-
-	memcpy(dev->policy_buf, dev->policy_base, dev->policy_sz);
-
-	amd_pmf_hex_dump_pb(dev);
-	if (pb_side_load)
-		amd_pmf_open_pb(dev, dev->dbgfs_dir);
-
-	return amd_pmf_start_policy_engine(dev);
-}
-
 static int amd_pmf_amdtee_ta_match(struct tee_ioctl_version_data *ver, const void *data)
 {
 	return ver->impl_id == TEE_IMPL_ID_AMDTEE;
@@ -455,22 +436,56 @@ int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev)
 		return ret;
 
 	INIT_DELAYED_WORK(&dev->pb_work, amd_pmf_invoke_cmd);
-	amd_pmf_set_dram_addr(dev, true);
-	amd_pmf_get_bios_buffer(dev);
+
+	ret = amd_pmf_set_dram_addr(dev, true);
+	if (ret)
+		goto error;
+
+	dev->policy_base = devm_ioremap(dev->dev, dev->policy_addr, dev->policy_sz);
+	if (!dev->policy_base) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	dev->policy_buf = kzalloc(dev->policy_sz, GFP_KERNEL);
+	if (!dev->policy_buf) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	memcpy(dev->policy_buf, dev->policy_base, dev->policy_sz);
+
+	amd_pmf_hex_dump_pb(dev);
+	if (pb_side_load)
+		amd_pmf_open_pb(dev, dev->dbgfs_dir);
+
 	dev->prev_data = kzalloc(sizeof(*dev->prev_data), GFP_KERNEL);
 	if (!dev->prev_data)
-		return -ENOMEM;
+		goto error;
 
-	return dev->smart_pc_enabled;
+	ret = amd_pmf_start_policy_engine(dev);
+	if (ret)
+		goto error;
+
+	return 0;
+
+error:
+	amd_pmf_deinit_smart_pc(dev);
+
+	return ret;
 }
 
 void amd_pmf_deinit_smart_pc(struct amd_pmf_dev *dev)
 {
-	if (pb_side_load)
+	if (pb_side_load && dev->esbin)
 		amd_pmf_remove_pb(dev);
 
+	cancel_delayed_work_sync(&dev->pb_work);
 	kfree(dev->prev_data);
+	dev->prev_data = NULL;
 	kfree(dev->policy_buf);
-	cancel_delayed_work_sync(&dev->pb_work);
+	dev->policy_buf = NULL;
+	kfree(dev->buf);
+	dev->buf = NULL;
 	amd_pmf_tee_deinit(dev);
 }
-- 
2.34.1