[PATCH] PCI: fix reference leak in pci_register_host_bridge()

[PATCH] PCI: fix reference leak in pci_register_host_bridge()

[Ma Ke]

Once device_register() failed, we should call put_device() to
decrement reference count for cleanup. Or it could cause memory leak.

device_register() includes device_add(). As comment of device_add()
says, 'if device_add() succeeds, you should call device_del() when you
want to get rid of it. If device_add() has not succeeded, use only
put_device() to drop the reference count'.

Found by code review.

Cc: stable@vger.kernel.org
Fixes: 37d6a0a6f470 ("PCI: Add pci_register_host_bridge() interface")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
---
 drivers/pci/probe.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 2e81ab0f5a25..73464ffbb0fc 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -974,8 +974,10 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge)
 	name = dev_name(&bus->dev);
 
 	err = device_register(&bus->dev);
-	if (err)
+	if (err) {
+		put_device(&bus->dev);
 		goto unregister;
+	}
 
 	pcibios_add_bus(bus);
 
-- 
2.25.1

Re: [PATCH] PCI: fix reference leak in pci_register_host_bridge()

[Markus Elfring]

> Once device_register() failed, we should call put_device() to
> decrement reference count for cleanup. Or it could cause memory leak.
>
> device_register() includes device_add(). As comment of device_add()
…

I doubt that the information from the second description paragraph is helpful
for this issue.


> Found by code review.

Would you become interested to check how many similar control flows
can still be detected by the means of automated advanced source code analyses?

Regards,
Markus