diff options
| author | Prashanth K <quic_prashk@quicinc.com> | 2023-05-05 12:18:37 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-05-29 17:22:43 +0300 |
| commit | 2f6ecb89fe8feb2b60a53325b0eeb9866d88909a (patch) | |
| tree | badb0c3ca10281bfc40a9477ea56584cd279aa71 | |
| parent | 24520e51fffb56f3931084b1426cb2404bda095a (diff) | |
| download | linux-2f6ecb89fe8feb2b60a53325b0eeb9866d88909a.tar.xz | |
usb: gadget: u_serial: Add null pointer check in gserial_suspend
Consider a case where gserial_disconnect has already cleared
gser->ioport. And if gserial_suspend gets called afterwards,
it will lead to accessing of gser->ioport and thus causing
null pointer dereference.
Avoid this by adding a null pointer check. Added a static
spinlock to prevent gser->ioport from becoming null after
the newly added null pointer check.
Fixes: aba3a8d01d62 ("usb: gadget: u_serial: add suspend resume callbacks")
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Link: https://lore.kernel.org/r/1683278317-11774-1-git-send-email-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/function/u_serial.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index a0ca47fbff0f..e5d522d54f6a 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -1420,10 +1420,19 @@ EXPORT_SYMBOL_GPL(gserial_disconnect); void gserial_suspend(struct gserial *gser) { - struct gs_port *port = gser->ioport; + struct gs_port *port; unsigned long flags; - spin_lock_irqsave(&port->port_lock, flags); + spin_lock_irqsave(&serial_port_lock, flags); + port = gser->ioport; + + if (!port) { + spin_unlock_irqrestore(&serial_port_lock, flags); + return; + } + + spin_lock(&port->port_lock); + spin_unlock(&serial_port_lock); port->suspended = true; spin_unlock_irqrestore(&port->port_lock, flags); } |