| Message ID | 20220707222045.1415417-3-pmalani@chromium.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Type-C switch driver and Type-C framework updates | expand |
Hello! On 7/8/22 1:20 AM, Prashant Malani wrote: > Similar to mux and orientation switch, add a handle for registered > retimer to the port, so that it has handles to the various switches > connected to it. > > Signed-off-by: Prashant Malani <pmalani@chromium.org> > --- > > Changes since v2: > - No changes. > > Changes since v1: > - Relinquish retimer reference during typec_release. > > drivers/usb/typec/class.c | 9 +++++++++ > drivers/usb/typec/class.h | 1 + > 2 files changed, 10 insertions(+) > > diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c > index 9062836bb638..f08e32d552b4 100644 > --- a/drivers/usb/typec/class.c > +++ b/drivers/usb/typec/class.c [...] > @@ -2249,6 +2251,13 @@ struct typec_port *typec_register_port(struct device *parent, > return ERR_PTR(ret); > } > > + port->retimer = typec_retimer_get(&port->dev); > + if (IS_ERR(port->retimer)) { > + ret = PTR_ERR(port->retimer); > + put_device(&port->dev); > + return ERR_PTR(ret); Why convert it to and fro, and not just return port->retimer? [...] MBR, Sergey
On Fri, Jul 08, 2022 at 11:46:44AM +0300, Sergey Shtylyov wrote: > Hello! > > On 7/8/22 1:20 AM, Prashant Malani wrote: > > > Similar to mux and orientation switch, add a handle for registered > > retimer to the port, so that it has handles to the various switches > > connected to it. > > > > Signed-off-by: Prashant Malani <pmalani@chromium.org> > > --- > > > > Changes since v2: > > - No changes. > > > > Changes since v1: > > - Relinquish retimer reference during typec_release. > > > > drivers/usb/typec/class.c | 9 +++++++++ > > drivers/usb/typec/class.h | 1 + > > 2 files changed, 10 insertions(+) > > > > diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c > > index 9062836bb638..f08e32d552b4 100644 > > --- a/drivers/usb/typec/class.c > > +++ b/drivers/usb/typec/class.c > [...] > > @@ -2249,6 +2251,13 @@ struct typec_port *typec_register_port(struct device *parent, > > return ERR_PTR(ret); > > } > > > > + port->retimer = typec_retimer_get(&port->dev); > > + if (IS_ERR(port->retimer)) { > > + ret = PTR_ERR(port->retimer); > > + put_device(&port->dev); > > + return ERR_PTR(ret); > > Why convert it to and fro, and not just return port->retimer? That would be a use-after-free as port might now be gone. thanks, greg k-h
On 7/8/22 12:21 PM, Greg Kroah-Hartman wrote: [...] >>> Similar to mux and orientation switch, add a handle for registered >>> retimer to the port, so that it has handles to the various switches >>> connected to it. >>> >>> Signed-off-by: Prashant Malani <pmalani@chromium.org> >>> --- >>> >>> Changes since v2: >>> - No changes. >>> >>> Changes since v1: >>> - Relinquish retimer reference during typec_release. >>> >>> drivers/usb/typec/class.c | 9 +++++++++ >>> drivers/usb/typec/class.h | 1 + >>> 2 files changed, 10 insertions(+) >>> >>> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c >>> index 9062836bb638..f08e32d552b4 100644 >>> --- a/drivers/usb/typec/class.c >>> +++ b/drivers/usb/typec/class.c >> [...] >>> @@ -2249,6 +2251,13 @@ struct typec_port *typec_register_port(struct device *parent, >>> return ERR_PTR(ret); >>> } >>> >>> + port->retimer = typec_retimer_get(&port->dev); >>> + if (IS_ERR(port->retimer)) { >>> + ret = PTR_ERR(port->retimer); >>> + put_device(&port->dev); >>> + return ERR_PTR(ret); >> >> Why convert it to and fro, and not just return port->retimer? > > That would be a use-after-free as port might now be gone. Ah, indeed! It would also ensue an explicit pointer cast... > thanks, > > greg k-h MBR, Sergey
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c index 9062836bb638..f08e32d552b4 100644 --- a/drivers/usb/typec/class.c +++ b/drivers/usb/typec/class.c @@ -12,6 +12,7 @@ #include <linux/slab.h> #include <linux/usb/pd_vdo.h> #include <linux/usb/typec_mux.h> +#include <linux/usb/typec_retimer.h> #include "bus.h" #include "class.h" @@ -1736,6 +1737,7 @@ static void typec_release(struct device *dev) ida_destroy(&port->mode_ids); typec_switch_put(port->sw); typec_mux_put(port->mux); + typec_retimer_put(port->retimer); kfree(port->cap); kfree(port); } @@ -2249,6 +2251,13 @@ struct typec_port *typec_register_port(struct device *parent, return ERR_PTR(ret); } + port->retimer = typec_retimer_get(&port->dev); + if (IS_ERR(port->retimer)) { + ret = PTR_ERR(port->retimer); + put_device(&port->dev); + return ERR_PTR(ret); + } + ret = device_add(&port->dev); if (ret) { dev_err(parent, "failed to register port (%d)\n", ret); diff --git a/drivers/usb/typec/class.h b/drivers/usb/typec/class.h index 43fcf9e37a8c..673b2952b074 100644 --- a/drivers/usb/typec/class.h +++ b/drivers/usb/typec/class.h @@ -55,6 +55,7 @@ struct typec_port { enum typec_orientation orientation; struct typec_switch *sw; struct typec_mux *mux; + struct typec_retimer *retimer; const struct typec_capability *cap; const struct typec_operations *ops;
Similar to mux and orientation switch, add a handle for registered retimer to the port, so that it has handles to the various switches connected to it. Signed-off-by: Prashant Malani <pmalani@chromium.org> --- Changes since v2: - No changes. Changes since v1: - Relinquish retimer reference during typec_release. drivers/usb/typec/class.c | 9 +++++++++ drivers/usb/typec/class.h | 1 + 2 files changed, 10 insertions(+)