6.1-stable review patch. If anyone has any objections, please let me know.
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From: Diogo Ivo diogo.ivo@tecnico.ulisboa.pt
commit c69ff68b097b0f53333114f1b2c3dc128f389596 upstream.
As part of the registration of a new 'struct usb_phy' with the USB PHY core via either usb_add_phy(struct usb_phy *x, ...) or usb_add_phy_dev(struct usb_phy *x) these functions call list_add_tail(&x->head, phy_list) in order for the new instance x to be stored in phy_list, a static list kept internally by the core.
After 7d21114dc6a2 ("usb: phy: Introduce one extcon device into usb phy") when executing either of the registration functions above it is possible that usb_add_extcon() fails, leading to either function returning before the call to list_add_tail(), leaving x->head uninitialized.
Then, when a driver tries to undo the failed registration by calling usb_remove_phy(struct usb_phy *x) there will be an unconditional call to list_del(&x->head) acting on an uninitialized variable, and thus a possible NULL pointer dereference.
Fix this by initializing x->head before usb_add_extcon() has a chance to fail. Note that this was not needed before 7d21114dc6a2 since list_add_phy() was executed unconditionally and it guaranteed that x->head was initialized.
Fixes: 7d21114dc6a2 ("usb: phy: Introduce one extcon device into usb phy") Cc: stable stable@kernel.org Signed-off-by: Diogo Ivo diogo.ivo@tecnico.ulisboa.pt Link: https://patch.msgid.link/20251121-diogo-smaug_typec-v2-1-5c37c1169d57@tecnic... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/phy/phy.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/usb/phy/phy.c +++ b/drivers/usb/phy/phy.c @@ -672,6 +672,8 @@ int usb_add_phy(struct usb_phy *x, enum return -EINVAL; }
+ INIT_LIST_HEAD(&x->head); + usb_charger_init(x); ret = usb_add_extcon(x); if (ret) @@ -722,6 +724,8 @@ int usb_add_phy_dev(struct usb_phy *x) return -EINVAL; }
+ INIT_LIST_HEAD(&x->head); + usb_charger_init(x); ret = usb_add_extcon(x); if (ret)