[v2,1/1] usbip: Use platform_device_register_full()
Commit Message
The code to create the child platform device is essentially the same as
what platform_device_register_full() does, so change over to use
that same function to reduce duplication.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v2: (hopefully) fixed run-time NULL-dereference (LKP)
drivers/usb/usbip/vhci_hcd.c | 55 +++++++++++++-----------------------
1 file changed, 20 insertions(+), 35 deletions(-)
Comments
On 10/6/23 10:43, Andy Shevchenko wrote:
> The code to create the child platform device is essentially the same as
> what platform_device_register_full() does, so change over to use
> that same function to reduce duplication.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v2: (hopefully) fixed run-time NULL-dereference (LKP)
> drivers/usb/usbip/vhci_hcd.c | 55 +++++++++++++-----------------------
> 1 file changed, 20 insertions(+), 35 deletions(-)
>
Looks good to me.
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
thanks,
-- Shuah
On Fri, Oct 06, 2023 at 07:43:12PM +0300, Andy Shevchenko wrote:
> The code to create the child platform device is essentially the same as
> what platform_device_register_full() does, so change over to use
> that same function to reduce duplication.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v2: (hopefully) fixed run-time NULL-dereference (LKP)
> drivers/usb/usbip/vhci_hcd.c | 55 +++++++++++++-----------------------
> 1 file changed, 20 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c
> index 37d1fc34e8a5..f845b91848b9 100644
> --- a/drivers/usb/usbip/vhci_hcd.c
> +++ b/drivers/usb/usbip/vhci_hcd.c
> - for (i = 0; i < vhci_num_controllers; i++) {
> - void *vhci = &vhcis[i];
The void *vhci here is intended
platform_device_add_data "Add a copy of platform specific data to the
platform device's platform_data pointer"
however, vhcis is static so it is not intended to be copied (the
pdev inside struct vhci might be the cause)
> - ret = platform_device_add_data(vhcis[i].pdev, &vhci, sizeof(void *));
> - if (ret)
> - goto err_driver_register;
> - }
> -
> ret = platform_driver_register(&vhci_driver);
> if (ret)
> goto err_driver_register;
>
> for (i = 0; i < vhci_num_controllers; i++) {
> - ret = platform_device_add(vhcis[i].pdev);
> + struct platform_device_info pdevinfo = {
> + .name = driver_name,
> + .id = i,
> + .data = &vhcis[i],
here should be a &vhci
> + .size_data = sizeof(void *),
> + };
> +
> + vhcis[i].pdev = platform_device_register_full(&pdevinfo);
> + ret = PTR_ERR_OR_ZERO(vhcis[i].pdev);
> }
> --
> 2.40.0.1.gaa8946217a0b
I have reproduced the boot error reported by syzbot in
https://lore.kernel.org/linux-usb/00000000000029242706077f3145@google.com/
https://lore.kernel.org/linux-usb/0000000000007634c1060793197c@google.com/
and adding back void *vhci fixed it
I'll send a patch.
@@ -1139,7 +1139,8 @@ static int hcd_name_to_id(const char *name)
static int vhci_setup(struct usb_hcd *hcd)
{
- struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
+ struct vhci *vhci = dev_get_platdata(hcd->self.controller);
+
if (usb_hcd_is_primary_hcd(hcd)) {
vhci->vhci_hcd_hs = hcd_to_vhci_hcd(hcd);
vhci->vhci_hcd_hs->vhci = vhci;
@@ -1256,7 +1257,7 @@ static int vhci_get_frame_number(struct usb_hcd *hcd)
/* FIXME: suspend/resume */
static int vhci_bus_suspend(struct usb_hcd *hcd)
{
- struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
+ struct vhci *vhci = dev_get_platdata(hcd->self.controller);
unsigned long flags;
dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
@@ -1270,7 +1271,7 @@ static int vhci_bus_suspend(struct usb_hcd *hcd)
static int vhci_bus_resume(struct usb_hcd *hcd)
{
- struct vhci *vhci = *((void **)dev_get_platdata(hcd->self.controller));
+ struct vhci *vhci = dev_get_platdata(hcd->self.controller);
int rc = 0;
unsigned long flags;
@@ -1337,7 +1338,7 @@ static const struct hc_driver vhci_hc_driver = {
static int vhci_hcd_probe(struct platform_device *pdev)
{
- struct vhci *vhci = *((void **)dev_get_platdata(&pdev->dev));
+ struct vhci *vhci = dev_get_platdata(&pdev->dev);
struct usb_hcd *hcd_hs;
struct usb_hcd *hcd_ss;
int ret;
@@ -1395,7 +1396,7 @@ static int vhci_hcd_probe(struct platform_device *pdev)
static void vhci_hcd_remove(struct platform_device *pdev)
{
- struct vhci *vhci = *((void **)dev_get_platdata(&pdev->dev));
+ struct vhci *vhci = dev_get_platdata(&pdev->dev);
/*
* Disconnects the root hub,
@@ -1430,7 +1431,7 @@ static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
if (!hcd)
return 0;
- vhci = *((void **)dev_get_platdata(hcd->self.controller));
+ vhci = dev_get_platdata(hcd->self.controller);
spin_lock_irqsave(&vhci->lock, flags);
@@ -1493,13 +1494,10 @@ static struct platform_driver vhci_driver = {
static void del_platform_devices(void)
{
- struct platform_device *pdev;
int i;
for (i = 0; i < vhci_num_controllers; i++) {
- pdev = vhcis[i].pdev;
- if (pdev != NULL)
- platform_device_unregister(pdev);
+ platform_device_unregister(vhcis[i].pdev);
vhcis[i].pdev = NULL;
}
sysfs_remove_link(&platform_bus.kobj, driver_name);
@@ -1519,45 +1517,32 @@ static int __init vhci_hcd_init(void)
if (vhcis == NULL)
return -ENOMEM;
- for (i = 0; i < vhci_num_controllers; i++) {
- vhcis[i].pdev = platform_device_alloc(driver_name, i);
- if (!vhcis[i].pdev) {
- i--;
- while (i >= 0)
- platform_device_put(vhcis[i--].pdev);
- ret = -ENOMEM;
- goto err_device_alloc;
- }
- }
- for (i = 0; i < vhci_num_controllers; i++) {
- void *vhci = &vhcis[i];
- ret = platform_device_add_data(vhcis[i].pdev, &vhci, sizeof(void *));
- if (ret)
- goto err_driver_register;
- }
-
ret = platform_driver_register(&vhci_driver);
if (ret)
goto err_driver_register;
for (i = 0; i < vhci_num_controllers; i++) {
- ret = platform_device_add(vhcis[i].pdev);
+ struct platform_device_info pdevinfo = {
+ .name = driver_name,
+ .id = i,
+ .data = &vhcis[i],
+ .size_data = sizeof(void *),
+ };
+
+ vhcis[i].pdev = platform_device_register_full(&pdevinfo);
+ ret = PTR_ERR_OR_ZERO(vhcis[i].pdev);
if (ret < 0) {
- i--;
- while (i >= 0)
- platform_device_del(vhcis[i--].pdev);
+ while (i--)
+ platform_device_unregister(vhcis[i].pdev);
goto err_add_hcd;
}
}
- return ret;
+ return 0;
err_add_hcd:
platform_driver_unregister(&vhci_driver);
err_driver_register:
- for (i = 0; i < vhci_num_controllers; i++)
- platform_device_put(vhcis[i].pdev);
-err_device_alloc:
kfree(vhcis);
return ret;
}