This is a note to let you know that I've just added the patch titled
usb: cdc_acm: Do not leak URB buffers
to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From f2924d4b16ae138c2de6a0e73f526fb638330858 Mon Sep 17 00:00:00 2001
From: Romain Izard romain.izard.pro@gmail.com Date: Thu, 20 Sep 2018 16:49:04 +0200 Subject: usb: cdc_acm: Do not leak URB buffers
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@gmail.com Acked-by: Oliver Neukum oneukum@suse.com Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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);