Commit a6792a0c authored by Yang Yingliang's avatar Yang Yingliang Committed by Jassi Brar
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mailbox: zynq-ipi: fix error handling while device_register() fails 



If device_register() fails, it has two issues:
1. The name allocated by dev_set_name() is leaked.
2. The parent of device is not NULL, device_unregister() is called
   in zynqmp_ipi_free_mboxes(), it will lead a kernel crash because
   of removing not added device.

Call put_device() to give up the reference, so the name is freed in
kobject_cleanup(). Add device registered check in zynqmp_ipi_free_mboxes()
to avoid null-ptr-deref.

Fixes: 4981b82b ("mailbox: ZynqMP IPI mailbox controller")
Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: default avatarJassi Brar <jaswinder.singh@linaro.org>
parent acabe12c

drivers/mailbox/zynqmp-ipi-mailbox.c

+3 −1
Original line number Diff line number Diff line
@@ -493,6 +493,7 @@ static int zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox *ipi_mbox, 
	ret = device_register(&ipi_mbox->dev);

	if (ret) {

		dev_err(dev, "Failed to register ipi mbox dev.\n");

		put_device(&ipi_mbox->dev);

		return ret;

	}

	mdev = &ipi_mbox->dev;
@@ -619,6 +620,7 @@ static void zynqmp_ipi_free_mboxes(struct zynqmp_ipi_pdata *pdata) 
		ipi_mbox = &pdata->ipi_mboxes[i];

		if (ipi_mbox->dev.parent) {

			mbox_controller_unregister(&ipi_mbox->mbox);

			if (device_is_registered(&ipi_mbox->dev))

				device_unregister(&ipi_mbox->dev);

		}

	}