From 1c06aff9b82fc3795a80feeb23935b9a44b07e71 Mon Sep 17 00:00:00 2001 From: Prashanth K Date: Tue, 6 May 2025 16:19:12 +0530 Subject: [PATCH] usb: gadget: u_serial: Avoid double unlock of serial_port_lock Avoid unlocking serial_port_lock twice in gserial_suspend(), this can occur if gserial_wakeup_host() fails. And since wakeup is performed outside spinlock, check if the port is valid before proceeding again. Fixes: 3baea29dc0a7 ("usb: gadget: u_serial: Implement remote wakeup capability") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/all/aBHatifO5bjR1yPt@stanley.mountain/ Signed-off-by: Prashanth K Link: https://lore.kernel.org/r/20250506104912.3750934-1-prashanth.k@oss.qualcomm.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/u_serial.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index 41dee7c8cc7c..ab544f6824be 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -1505,6 +1505,13 @@ void gserial_suspend(struct gserial *gser) spin_unlock_irqrestore(&serial_port_lock, flags); if (!gserial_wakeup_host(gser)) return; + + /* Check if port is valid after acquiring lock back */ + spin_lock_irqsave(&serial_port_lock, flags); + if (!port) { + spin_unlock_irqrestore(&serial_port_lock, flags); + return; + } } spin_lock(&port->port_lock); -- 2.25.1