[PATCH 6.8 432/715] NTB: fix possible name leak in ntb_register_device()

Sasha Levin
2024-03-24T22:42:05Z

From: Yang Yingliang <yangyingliang@huawei.com>

[ 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@huawei.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20231201033057.1399131-1-yangyingliang@huaweicloud.com
[mani: reworded commit message]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 e75a2af77328e..5b84821c0d602 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -1275,15 +1275,11 @@ 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