Messages in this thread |  | | Date | Tue, 5 May 2026 02:40:12 +0000 | | From | Tzung-Bi Shih <> | | Subject | Re: [PATCH 2/5] platform/chrome: cros_ec_lpc: fix reference leak on failed device registration |
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On Mon, May 04, 2026 at 01:08:44PM +0300, Vastargazing wrote: > When platform_device_register() fails in cros_ec_lpc_init(), the embedded > struct device has already been initialized by device_initialize() inside > platform_device_register(). The error path unregisters the driver but > returns without dropping the device reference: > > cros_ec_lpc_init() > -> platform_device_register(&cros_ec_lpc_device) > -> device_initialize(&cros_ec_lpc_device.dev) /* kref = 1 */ > -> platform_device_add(&cros_ec_lpc_device) /* fails */ > <- platform_driver_unregister() called, but kref still 1 > > Per platform_device_register() kernel-doc: > > NOTE: _Never_ directly free @pdev after calling this function, even if > it returned an error! Always use platform_device_put() to give up the > reference initialised in this function instead. > > Fix this by calling platform_device_put() before unregistering the driver. > > Fixes: 5f454bdf6353 ("platform/chrome: cros_ec_lpc: Register the driver if ACPI entry is missing.") > Cc: stable@vger.kernel.org > Assisted-by: GitHub Copilot (Claude Sonnet 4.5) > Signed-off-by: Vastargazing <vebohr@gmail.com> > --- > drivers/platform/chrome/cros_ec_lpc.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c > index 78cfff80cdea..cb3ff76d29e9 100644 > --- a/drivers/platform/chrome/cros_ec_lpc.c > +++ b/drivers/platform/chrome/cros_ec_lpc.c > @@ -892,6 +892,7 @@ static int __init cros_ec_lpc_init(void) > ret = platform_device_register(&cros_ec_lpc_device); > if (ret) { > pr_err(DRV_NAME ": can't register device: %d\n", ret); > + platform_device_put(&cros_ec_lpc_device); > platform_driver_unregister(&cros_ec_lpc_driver); > } > }
The patch is identical to [1]. See also [2].
[1] https://lore.kernel.org/chrome-platform/20260415175707.3640225-1-lgs201920130244@gmail.com/ [2] https://lore.kernel.org/chrome-platform/CANUHTR9_c=msO7mAax=Aj4U--GB=2ozserOvrTU8WueqdSMN8Q@mail.gmail.com/
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