When the ACM TTY port is disconnected, the URBs it uses must be killed, and
then the buffers must be freed. Unfortunately a previous refactor removed
the code freeing the buffers because it looked extremely similar to the
code killing the URBs.
As a result, there were many new leaks for each plug/unplug cycle of a
CDC-ACM device, that were detected by kmemleak.
Restore the missing code, and the memory leak is removed.
Fixes: ba8c931ded8d ("cdc-acm: refactor killing urbs")
Signed-off-by: Romain Izard <romain.izard.pro@xxxxxxxxx>
---
drivers/usb/class/cdc-acm.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index f9b40a9dc4d3..bc03b0a690b4 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1514,6 +1514,7 @@ static void acm_disconnect(struct usb_interface *intf)
{
struct acm *acm = usb_get_intfdata(intf);
struct tty_struct *tty;
+ int i;
/* sibling interface is already cleaning up */
if (!acm)
@@ -1544,6 +1545,11 @@ static void acm_disconnect(struct usb_interface *intf)
tty_unregister_device(acm_tty_driver, acm->minor);
+ usb_free_urb(acm->ctrlurb);
+ for (i = 0; i < ACM_NW; i++)
+ usb_free_urb(acm->wb[i].urb);
+ for (i = 0; i < acm->rx_buflimit; i++)
+ usb_free_urb(acm->read_urbs[i]);
acm_write_buffers_free(acm);
usb_free_coherent(acm->dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
acm_read_buffers_free(acm);
--
2.17.1
