Re: [PATCH v2 RESEND] PCI: fix reference leak in pci_register_host_bridge()

Bjorn Helgaas
2025-02-27T22:01:26Z

On Tue, Feb 25, 2025 at 10:14:40AM +0800, Ma Ke wrote:
> 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>

Applied to pci/enumeration for v6.15, thanks!

> ---
> Changes in v2:
> - modified the patch description.
> ---
> 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 246744d8d268..7b1d7ce3a83e 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -1018,8 +1018,10 @@ 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
>