Op 17-02-2025 om 13:03 schreef Prashanth K:
Currently the USB gadget will be set as bus-powered based solely on whether its bMaxPower is greater than 100mA, but this may miss devices that may legitimately draw less than 100mA but still want to report as bus-powered. Similarly during suspend & resume, USB gadget is incorrectly marked as bus/self powered without checking the bmAttributes field. Fix these by configuring the USB gadget as self or bus powered based on bmAttributes, and explicitly set it as bus-powered if it draws more than 100mA.
Cc: stable@vger.kernel.org Fixes: 5e5caf4fa8d3 ("usb: gadget: composite: Inform controller driver of self-powered") Signed-off-by: Prashanth K prashanth.k@oss.qualcomm.com
Changes in v2:
Didn't change anything from RFC.
Link to RFC: https://lore.kernel.org/all/20250204105908.2255686-1-prashanth.k@oss.qualcom...
drivers/usb/gadget/composite.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index bdda8c74602d..1fb28bbf6c45 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -1050,10 +1050,11 @@ static int set_config(struct usb_composite_dev *cdev, else usb_gadget_set_remote_wakeup(gadget, 0); done:
- if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
usb_gadget_set_selfpowered(gadget);- else
- if (power > USB_SELF_POWER_VBUS_MAX_DRAW ||
!(c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
Please check this change again. From line 983-884 there is a `goto done`. in case `c` is NULL. So, there will be a potential NULL pointer dereference with your change.
usb_gadget_clear_selfpowered(gadget);
- else
usb_gadget_set_selfpowered(gadget);usb_gadget_vbus_draw(gadget, power); if (result >= 0 && cdev->delayed_status) [...]