2022-01-20 01:08:36

by Heikki Krogerus

Subject: [PATCH] usb: typec: Only attempt to link USB ports if there is fwnode

The code that creates the links to the USB ports attached to
a connector inside the system assumed that the ACPI nodes
(fwnodes) always exist for the connectors, but it can not do
that.

There is no guarantee that every USB Type-C connector has
ACPI device node representing it in the ACPI tables, and
even if there are the nodes in the ACPI tables, the _STA
method in those nodes may still return 0 (which means the
device does not exist from ACPI PoW).

This fixes NULL pointer dereference that happens if the
nodes are missing.

Reported-and-tested-by: Robert Święcki <[email protected]>
Reported-by: Mikhail Gavrilov <[email protected]>
Fixes: 730b49aac426 ("usb: typec: port-mapper: Convert to the component framework")
Signed-off-by: Heikki Krogerus <[email protected]>
---
Hi guys,

Mikhail, I got confirmation from Robert that the patch fixes the
issue.

thanks,
---
drivers/usb/typec/port-mapper.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/port-mapper.c b/drivers/usb/typec/port-mapper.c
index 07d307418b470..b6e0c6acc628c 100644
--- a/drivers/usb/typec/port-mapper.c
+++ b/drivers/usb/typec/port-mapper.c
@@ -56,6 +56,9 @@ int typec_link_ports(struct typec_port *con)
{
struct each_port_arg arg = { .port = con, .match = NULL };

+ if (!has_acpi_companion(&con->dev))
+ return 0;
+
bus_for_each_dev(&acpi_bus_type, NULL, &arg, typec_port_match);

/*
@@ -74,5 +77,6 @@ int typec_link_ports(struct typec_port *con)

void typec_unlink_ports(struct typec_port *con)
{
- component_master_del(&con->dev, &typec_aggregate_ops);
+ if (has_acpi_companion(&con->dev))
+ component_master_del(&con->dev, &typec_aggregate_ops);
}
--
2.34.1

2022-01-24 18:54:17

by Heikki Krogerus

Subject: Re: [PATCH] usb: typec: Only attempt to link USB ports if there is fwnode

On Tue, Jan 18, 2022 at 12:36:27PM +0300, Heikki Krogerus wrote:
> The code that creates the links to the USB ports attached to
> a connector inside the system assumed that the ACPI nodes
> (fwnodes) always exist for the connectors, but it can not do
> that.
>
> There is no guarantee that every USB Type-C connector has
> ACPI device node representing it in the ACPI tables, and
> even if there are the nodes in the ACPI tables, the _STA
> method in those nodes may still return 0 (which means the
> device does not exist from ACPI PoW).
>
> This fixes NULL pointer dereference that happens if the
> nodes are missing.

I'll resend this togher wit the other fix.

thanks,

> Reported-and-tested-by: Robert Święcki <[email protected]>
> Reported-by: Mikhail Gavrilov <[email protected]>
> Fixes: 730b49aac426 ("usb: typec: port-mapper: Convert to the component framework")
> Signed-off-by: Heikki Krogerus <[email protected]>
> ---
> Hi guys,
>
> Mikhail, I got confirmation from Robert that the patch fixes the
> issue.
>
> thanks,
> ---
> drivers/usb/typec/port-mapper.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/port-mapper.c b/drivers/usb/typec/port-mapper.c
> index 07d307418b470..b6e0c6acc628c 100644
> --- a/drivers/usb/typec/port-mapper.c
> +++ b/drivers/usb/typec/port-mapper.c
> @@ -56,6 +56,9 @@ int typec_link_ports(struct typec_port *con)
> {
> struct each_port_arg arg = { .port = con, .match = NULL };
>
> + if (!has_acpi_companion(&con->dev))
> + return 0;
> +
> bus_for_each_dev(&acpi_bus_type, NULL, &arg, typec_port_match);
>
> /*
> @@ -74,5 +77,6 @@ int typec_link_ports(struct typec_port *con)
>
> void typec_unlink_ports(struct typec_port *con)
> {
> - component_master_del(&con->dev, &typec_aggregate_ops);
> + if (has_acpi_companion(&con->dev))
> + component_master_del(&con->dev, &typec_aggregate_ops);
> }
> --
> 2.34.1

--
heikki