From 1854082fe0ddb81bc93d1f8e8a00554217fd09d1 Mon Sep 17 00:00:00 2001 From: David Carlier Date: Fri, 8 May 2026 21:19:58 +0100 Subject: [PATCH] phy: apple: atc: Fix typec switch/mux leak on unbind atcphy_probe_switch() and atcphy_probe_mux() discard the pointers returned by typec_switch_register() and typec_mux_register(). The platform driver has no .remove callback, so when the driver unbinds (e.g. via sysfs unbind) neither typec_switch_unregister() nor typec_mux_unregister() is called. The framework reference taken in typec_switch_register() (device_initialize() + device_add() in drivers/usb/typec/mux.c) is therefore never dropped and the typec_switch_dev / typec_mux_dev objects stay live forever, with their sysfs entries under the typec_mux class also left behind. A subsequent rebind cannot recreate them with the same fwnode-derived name. Save the registered handles and unregister them through devm_add_action_or_reset() so framework registration is torn down in step with the driver's other devm-managed state. While here, drop struct apple_atcphy::sw and ::mux: they were declared with the consumer-side types (typec_switch *, typec_mux *) instead of the provider-side types and were never assigned. Scope of the fix ================ This patch fixes the registration leak only. It does not close the use-after-free window that arises when a consumer that obtained a reference via fwnode_typec_switch_get() / fwnode_typec_mux_get() outlives the provider unbind: such consumers keep the underlying typec_switch_dev / typec_mux_dev alive past device_unregister(), and a later typec_switch_set() / typec_mux_set() still invokes the registered atcphy_sw_set() / atcphy_mux_set(), which dereferences the freed apple_atcphy through typec_{switch,mux}_get_drvdata(). On Apple Silicon the relevant consumers are the typec port and the cd321x controller registered by drivers/usb/typec/tipd/core.c. Cable plug / orientation events and alt-mode transitions trigger the .set callbacks via: tps6598x_interrupt() drivers/usb/typec/tipd/core.c tps6598x_handle_plug_event() tps6598x_connect()/_disconnect() typec_set_orientation() drivers/usb/typec/class.c typec_switch_set(port->sw) drivers/usb/typec/mux.c atcphy_sw_set() drivers/phy/apple/atc.c cd321x_update_work() drivers/usb/typec/tipd/core.c cd321x_typec_update_mode() typec_mux_set(cd321x->mux) drivers/usb/typec/mux.c atcphy_mux_set() drivers/phy/apple/atc.c Closing that window requires framework support for invalidating consumer-held references on provider unbind. The same consumer-survives-provider pattern has been discussed for the PHY framework [1] and is out of scope here. [1] https://lore.kernel.org/linux-phy/aZejMSJ9qqRWb2pX@google.com/ Fixes: 8e98ca1e74db ("phy: apple: Add Apple Type-C PHY") Signed-off-by: David Carlier Reviewed-by: Vladimir Oltean Tested-by: Joshua Peisach Link: https://lkml.kernel.org/r/6ec1ed08328340db42655287afd5fa4067316b11.camel@perches.com Link: https://patch.msgid.link/20260508201958.30060-1-devnexen@gmail.com Signed-off-by: Vinod Koul --- drivers/phy/apple/atc.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/phy/apple/atc.c b/drivers/phy/apple/atc.c index e9d106f135c5..4156fabad742 100644 --- a/drivers/phy/apple/atc.c +++ b/drivers/phy/apple/atc.c @@ -628,9 +628,6 @@ struct apple_atcphy { struct reset_controller_dev rcdev; - struct typec_switch *sw; - struct typec_mux *mux; - struct mutex lock; }; @@ -2066,15 +2063,25 @@ static int atcphy_sw_set(struct typec_switch_dev *sw, enum typec_orientation ori return 0; } +static void atcphy_typec_switch_unregister(void *data) +{ + typec_switch_unregister(data); +} + static int atcphy_probe_switch(struct apple_atcphy *atcphy) { + struct typec_switch_dev *sw; struct typec_switch_desc sw_desc = { .drvdata = atcphy, .fwnode = atcphy->dev->fwnode, .set = atcphy_sw_set, }; - return PTR_ERR_OR_ZERO(typec_switch_register(atcphy->dev, &sw_desc)); + sw = typec_switch_register(atcphy->dev, &sw_desc); + if (IS_ERR(sw)) + return PTR_ERR(sw); + + return devm_add_action_or_reset(atcphy->dev, atcphy_typec_switch_unregister, sw); } static int atcphy_mux_set(struct typec_mux_dev *mux, struct typec_mux_state *state) @@ -2146,15 +2153,25 @@ static int atcphy_mux_set(struct typec_mux_dev *mux, struct typec_mux_state *sta return atcphy_configure(atcphy, target_mode); } +static void atcphy_typec_mux_unregister(void *data) +{ + typec_mux_unregister(data); +} + static int atcphy_probe_mux(struct apple_atcphy *atcphy) { + struct typec_mux_dev *mux; struct typec_mux_desc mux_desc = { .drvdata = atcphy, .fwnode = atcphy->dev->fwnode, .set = atcphy_mux_set, }; - return PTR_ERR_OR_ZERO(typec_mux_register(atcphy->dev, &mux_desc)); + mux = typec_mux_register(atcphy->dev, &mux_desc); + if (IS_ERR(mux)) + return PTR_ERR(mux); + + return devm_add_action_or_reset(atcphy->dev, atcphy_typec_mux_unregister, mux); } static int atcphy_load_tunables(struct apple_atcphy *atcphy)