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@xxxxxxxxxxxxxxx
Fixes: 5e5caf4fa8d3 ("usb: gadget: composite: Inform controller driver of self-powered")
Signed-off-by: Prashanth K <prashanth.k@xxxxxxxxxxxxxxxx>
---
Changes in v2:
- Didn't change anything from RFC.
- Link to RFC: https://lore.kernel.org/all/20250204105908.2255686-1-prashanth.k@xxxxxxxxxxxxxxxx/
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)
[...]
