From cae2bc768d176bfbdad7035bbcc3cdc973eb7984 Mon Sep 17 00:00:00 2001
From: Jaejoong Kim <climbbb.kim@gmail.com>
Date: Thu, 21 Jun 2018 17:45:05 +0900
Subject: [PATCH] usb: cdc-acm: Decrement tty port's refcount if probe() fail
The cdc-acm driver does not have a refcount of itself, but uses a
tty_port's refcount. That is, if the refcount of tty_port is '0', we
can clean up the cdc-acm driver by calling the .destruct()
callback function of struct tty_port_operations.
The problem is the destruct() callback function is not called if
the probe() fails, because tty_port's refcount is not zero. So,
add tty_port_put() when probe() fails.
Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/class/cdc-acm.c | 35 +++++++++++++++++------------------
1 file changed, 17 insertions(+), 18 deletions(-)
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 7b366a6c0b493..ed0475c6602d5 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1378,6 +1378,9 @@ static int acm_probe(struct usb_interface *intf,
if (acm == NULL)
goto alloc_fail;
+ tty_port_init(&acm->port);
+ acm->port.ops = &acm_port_ops;
+
minor = acm_alloc_minor(acm);
if (minor < 0)
goto alloc_fail1;
@@ -1413,22 +1416,20 @@ static int acm_probe(struct usb_interface *intf,
acm->out = usb_sndintpipe(usb_dev, epwrite->bEndpointAddress);
else
acm->out = usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress);
- tty_port_init(&acm->port);
- acm->port.ops = &acm_port_ops;
init_usb_anchor(&acm->delayed);
acm->quirks = quirks;
buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
if (!buf)
- goto alloc_fail2;
+ goto alloc_fail1;
acm->ctrl_buffer = buf;
if (acm_write_buffers_alloc(acm) < 0)
- goto alloc_fail4;
+ goto alloc_fail2;
acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
if (!acm->ctrlurb)
- goto alloc_fail5;
+ goto alloc_fail3;
for (i = 0; i < num_rx_buf; i++) {
struct acm_rb *rb = &(acm->read_buffers[i]);
@@ -1437,13 +1438,13 @@ static int acm_probe(struct usb_interface *intf,
rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
&rb->dma);
if (!rb->base)
- goto alloc_fail6;
+ goto alloc_fail4;
rb->index = i;
rb->instance = acm;
urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb)
- goto alloc_fail6;
+ goto alloc_fail4;
urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
urb->transfer_dma = rb->dma;
@@ -1465,7 +1466,7 @@ static int acm_probe(struct usb_interface *intf,
snd->urb = usb_alloc_urb(0, GFP_KERNEL);
if (snd->urb == NULL)
- goto alloc_fail7;
+ goto alloc_fail5;
if (usb_endpoint_xfer_int(epwrite))
usb_fill_int_urb(snd->urb, usb_dev, acm->out,
@@ -1483,7 +1484,7 @@ static int acm_probe(struct usb_interface *intf,
i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
if (i < 0)
- goto alloc_fail7;
+ goto alloc_fail5;
if (h.usb_cdc_country_functional_desc) { /* export the country data */
struct usb_cdc_country_functional_desc * cfd =
@@ -1542,7 +1543,7 @@ static int acm_probe(struct usb_interface *intf,
&control_interface->dev);
if (IS_ERR(tty_dev)) {
rv = PTR_ERR(tty_dev);
- goto alloc_fail8;
+ goto alloc_fail6;
}
if (quirks & CLEAR_HALT_CONDITIONS) {
@@ -1551,7 +1552,7 @@ static int acm_probe(struct usb_interface *intf,
}
return 0;
-alloc_fail8:
+alloc_fail6:
if (acm->country_codes) {
device_remove_file(&acm->control->dev,
&dev_attr_wCountryCodes);
@@ -1560,23 +1561,21 @@ static int acm_probe(struct usb_interface *intf,
kfree(acm->country_codes);
}
device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
-alloc_fail7:
+alloc_fail5:
usb_set_intfdata(intf, NULL);
for (i = 0; i < ACM_NW; i++)
usb_free_urb(acm->wb[i].urb);
-alloc_fail6:
+alloc_fail4:
for (i = 0; i < num_rx_buf; i++)
usb_free_urb(acm->read_urbs[i]);
acm_read_buffers_free(acm);
usb_free_urb(acm->ctrlurb);
-alloc_fail5:
+alloc_fail3:
acm_write_buffers_free(acm);
-alloc_fail4:
- usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
alloc_fail2:
- acm_release_minor(acm);
+ usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
alloc_fail1:
- kfree(acm);
+ tty_port_put(&acm->port);
alloc_fail:
return rv;
}
--
GitLab