[PATCH 5.15 206/317] NTB: fix possible name leak in ntb_register_device()

[Sasha Levin]

From: Yang Yingliang <yangyingliang@xxxxxxxxxx>

[ Upstream commit aebfdfe39b9327a3077d0df8db3beb3160c9bdd0 ]

If device_register() fails in ntb_register_device(), the device name
allocated by dev_set_name() should be freed. As per the comment in
device_register(), callers should use put_device() to give up the
reference in the error path. So fix this by calling put_device() in the
error path so that the name can be freed in kobject_cleanup().

As a result of this, put_device() in the error path of
ntb_register_device() is removed and the actual error is returned.

Fixes: a1bd3baeb2f1 ("NTB: Add NTB hardware abstraction layer")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Link: https://lore.kernel.org/r/20231201033057.1399131-1-yangyingliang@xxxxxxxxxxxxxxx
[mani: reworded commit message]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/ntb/core.c                            | 8 +++++++-
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 6 +-----
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/ntb/core.c b/drivers/ntb/core.c
index 27dd93deff6e5..d702bee780826 100644
--- a/drivers/ntb/core.c
+++ b/drivers/ntb/core.c
@@ -100,6 +100,8 @@ EXPORT_SYMBOL(ntb_unregister_client);
 
 int ntb_register_device(struct ntb_dev *ntb)
 {
+	int ret;
+
 	if (!ntb)
 		return -EINVAL;
 	if (!ntb->pdev)
@@ -120,7 +122,11 @@ int ntb_register_device(struct ntb_dev *ntb)
 	ntb->ctx_ops = NULL;
 	spin_lock_init(&ntb->ctx_lock);
 
-	return device_register(&ntb->dev);
+	ret = device_register(&ntb->dev);
+	if (ret)
+		put_device(&ntb->dev);
+
+	return ret;
 }
 EXPORT_SYMBOL(ntb_register_device);
 
diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 138742af51707..d4cd4bd4a0881 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -1242,15 +1242,11 @@ static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	ret = ntb_register_device(&ndev->ntb);
 	if (ret) {
 		dev_err(dev, "Failed to register NTB device\n");
-		goto err_register_dev;
+		return ret;
 	}
 
 	dev_dbg(dev, "PCI Virtual NTB driver loaded\n");
 	return 0;
-
-err_register_dev:
-	put_device(&ndev->ntb.dev);
-	return -EINVAL;
 }
 
 static struct pci_device_id pci_vntb_table[] = {
-- 
2.43.0