* [PATCH] Drivers: hv: vmbus: Check ACPI companion before use
@ 2026-10-17 6:43 Jiale Yao
2026-10-17 7:40 ` jiale yao
2026-10-19 9:24 ` [PATCH] " Naman Jain
0 siblings, 2 replies; 3+ messages in thread
From: Jiale Yao @ 2026-10-17 6:43 UTC (permalink / raw)
To: Haiyang Zhang, Wei Liu, Dexuan Cui, linux-hyperv, linux-kernel; +Cc: Jiale Yao
Platform drivers can be forced to bind to devices outside their match
tables through driver_override. vmbus_acpi_add() assumes that every bound
device has an ACPI companion and dereferences it without checking.
Return -ENODEV when the companion is absent to avoid a NULL pointer
dereference.
Signed-off-by: Jiale Yao <yaojiale02@163.com>
---
drivers/hv/vmbus_drv.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 4692687cdbf3..28f459679406 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -2571,10 +2571,14 @@ EXPORT_SYMBOL_GPL(vmbus_free_mmio);
#ifdef CONFIG_ACPI
static int vmbus_acpi_add(struct platform_device *pdev)
{
+ struct acpi_device *ancestor;
+ struct acpi_device *device;
acpi_status result;
int ret_val = -ENODEV;
- struct acpi_device *ancestor;
- struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
+
+ device = ACPI_COMPANION(&pdev->dev);
+ if (!device)
+ return -ENODEV;
vmbus_root_device = &device->dev;
--
2.34.1
^ permalink raw reply [flat|nested] 3+ messages in thread* Re:[PATCH] Drivers: hv: vmbus: Check ACPI companion before use
2026-10-17 6:43 [PATCH] Drivers: hv: vmbus: Check ACPI companion before use Jiale Yao
@ 2026-10-17 7:40 ` jiale yao
2026-10-19 9:24 ` [PATCH] " Naman Jain
1 sibling, 0 replies; 3+ messages in thread
From: jiale yao @ 2026-10-17 7:40 UTC (permalink / raw)
To: Haiyang Zhang, Wei Liu, Dexuan Cui, linux-hyperv, linux-kernel
At 2026-10-17 14:43:13, "Jiale Yao" <yaojiale02@163.com> wrote:
>Platform drivers can be forced to bind to devices outside their match
>tables through driver_override. vmbus_acpi_add() assumes that every bound
>device has an ACPI companion and dereferences it without checking.
>
>Return -ENODEV when the companion is absent to avoid a NULL pointer
>dereference.
>
Fixes: 9c8434238041 ("Drivers: hv: vmbus: Convert acpi_device to more generic platform_device")
>Signed-off-by: Jiale Yao <yaojiale02@163.com>
>---
> drivers/hv/vmbus_drv.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
>index 4692687cdbf3..28f459679406 100644
>--- a/drivers/hv/vmbus_drv.c
>+++ b/drivers/hv/vmbus_drv.c
>@@ -2571,10 +2571,14 @@ EXPORT_SYMBOL_GPL(vmbus_free_mmio);
> #ifdef CONFIG_ACPI
> static int vmbus_acpi_add(struct platform_device *pdev)
> {
>+ struct acpi_device *ancestor;
>+ struct acpi_device *device;
> acpi_status result;
> int ret_val = -ENODEV;
>- struct acpi_device *ancestor;
>- struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
>+
>+ device = ACPI_COMPANION(&pdev->dev);
>+ if (!device)
>+ return -ENODEV;
>
> vmbus_root_device = &device->dev;
>
>--
>2.34.1
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] Drivers: hv: vmbus: Check ACPI companion before use
2026-10-17 6:43 [PATCH] Drivers: hv: vmbus: Check ACPI companion before use Jiale Yao
2026-10-17 7:40 ` jiale yao
@ 2026-10-19 9:24 ` Naman Jain
1 sibling, 0 replies; 3+ messages in thread
From: Naman Jain @ 2026-10-19 9:24 UTC (permalink / raw)
To: Jiale Yao, Haiyang Zhang, Wei Liu, Dexuan Cui, linux-hyperv,
linux-kernel
On 10/17/2026 12:13 PM, Jiale Yao wrote:
> Platform drivers can be forced to bind to devices outside their match
> tables through driver_override. vmbus_acpi_add() assumes that every bound
> device has an ACPI companion and dereferences it without checking.
>
> Return -ENODEV when the companion is absent to avoid a NULL pointer
> dereference.
>
> Signed-off-by: Jiale Yao <yaojiale02@163.com>
> ---
> drivers/hv/vmbus_drv.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index 4692687cdbf3..28f459679406 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -2571,10 +2571,14 @@ EXPORT_SYMBOL_GPL(vmbus_free_mmio);
> #ifdef CONFIG_ACPI
> static int vmbus_acpi_add(struct platform_device *pdev)
> {
> + struct acpi_device *ancestor;
> + struct acpi_device *device;
> acpi_status result;
> int ret_val = -ENODEV;
> - struct acpi_device *ancestor;
> - struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
> +
> + device = ACPI_COMPANION(&pdev->dev);
> + if (!device)
> + return -ENODEV;
>
> vmbus_root_device = &device->dev;
>
Reviewed-by: Naman Jain <namjain@linux.microsoft.com>
Regards,
Naman
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2026-10-19 9:24 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2026-10-17 6:43 [PATCH] Drivers: hv: vmbus: Check ACPI companion before use Jiale Yao
2026-10-17 7:40 ` jiale yao
2026-10-19 9:24 ` [PATCH] " Naman Jain
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