From: Yang Yingliang yangyingliang@huawei.com
[ Upstream commit a6792a0cdef0b1c2d77920246283a72537e60e94 ]
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: 4981b82ba2ff ("mailbox: ZynqMP IPI mailbox controller") Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Jassi Brar jaswinder.singh@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mailbox/zynqmp-ipi-mailbox.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/mailbox/zynqmp-ipi-mailbox.c b/drivers/mailbox/zynqmp-ipi-mailbox.c index f44079d62b1a..527204c6d5cd 100644 --- a/drivers/mailbox/zynqmp-ipi-mailbox.c +++ b/drivers/mailbox/zynqmp-ipi-mailbox.c @@ -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; @@ -619,7 +620,8 @@ 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); - device_unregister(&ipi_mbox->dev); + if (device_is_registered(&ipi_mbox->dev)) + device_unregister(&ipi_mbox->dev); } } }