[PATCH v2 2/4] coresight: ultrasoc-smb: Config SMB buffer before register sink

From: Junhao He
Date: Sat Oct 21 2023 - 04:38:08 EST


The SMB dirver register the enable/disable sysfs interface in function
smb_register_sink(), however the buffer depends on the following
configuration to work well. So it'll be possible for user to access an
unreset one.

Move the config buffer operation to before register_sink().

Fixes: 06f5c2926aaa ("drivers/coresight: Add UltraSoc System Memory Buffer driver")
Signed-off-by: Junhao He <hejunhao3@xxxxxxxxxx>
---
drivers/hwtracing/coresight/ultrasoc-smb.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/hwtracing/coresight/ultrasoc-smb.c b/drivers/hwtracing/coresight/ultrasoc-smb.c
index 0a0fe9fcc57f..c61450f74cb1 100644
--- a/drivers/hwtracing/coresight/ultrasoc-smb.c
+++ b/drivers/hwtracing/coresight/ultrasoc-smb.c
@@ -583,38 +583,31 @@ static int smb_probe(struct platform_device *pdev)
return ret;
}

+ ret = smb_config_inport(dev, true);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, drvdata);
spin_lock_init(&drvdata->spinlock);
drvdata->pid = -1;

ret = smb_register_sink(pdev, drvdata);
if (ret) {
+ smb_config_inport(&pdev->dev, false);
dev_err(dev, "Failed to register SMB sink\n");
return ret;
}

- ret = smb_config_inport(dev, true);
- if (ret) {
- smb_unregister_sink(drvdata);
- return ret;
- }
-
- platform_set_drvdata(pdev, drvdata);
-
return 0;
}

static int smb_remove(struct platform_device *pdev)
{
struct smb_drv_data *drvdata = platform_get_drvdata(pdev);
- int ret;
-
- ret = smb_config_inport(&pdev->dev, false);
- if (ret)
- return ret;

smb_unregister_sink(drvdata);

- return 0;
+ return smb_config_inport(&pdev->dev, false);
}

#ifdef CONFIG_ACPI
--
2.33.0