testo: Fix USB device list leak

The testo driver uses libusb_get_device_list() but neglects to call the
matching libusb_device_list_free() on the error path. This will leak the
memory allocated for the list as well as all the devices.

To address the issue use sr_usb_open() instead of open-coding its
functionality. sr_usb_open() correctly handles freeing the device list.

The issue was discovered using the following coccinelle semantic patch:
// <smpl>
@@
identifier devlist;
expression ctx, ret;
statement S;
@@
(
 libusb_get_device_list(ctx, &devlist);
|
 ret = libusb_get_device_list(ctx, &devlist);
 if (ret < 0) S
)
... when != libusb_free_device_list(devlist, ...)
*return ...;
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
This commit is contained in:
Lars-Peter Clausen 2016-05-06 13:25:14 +02:00
parent ceb2da179f
commit b75dc14a94
1 changed files with 5 additions and 19 deletions

View File

@ -150,27 +150,13 @@ static int dev_open(struct sr_dev_inst *sdi)
struct sr_dev_driver *di = sdi->driver;
struct drv_context *drvc = di->context;
struct sr_usb_dev_inst *usb;
libusb_device **devlist;
int ret, i;
char connection_id[64];
int ret;
usb = sdi->conn;
libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
for (i = 0; devlist[i]; i++) {
usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
if (strcmp(sdi->connection_id, connection_id))
continue;
if ((ret = libusb_open(devlist[i], &usb->devhdl))) {
sr_err("Failed to open device: %s.", libusb_error_name(ret));
return SR_ERR;
}
break;
}
libusb_free_device_list(devlist, 1);
if (!devlist[i]) {
sr_err("Device not found.");
return SR_ERR;
}
ret = sr_usb_open(drvc->sr_ctx->libusb_ctx, usb);
if (ret != SR_OK)
return ret;
if (libusb_has_capability(LIBUSB_CAP_SUPPORTS_DETACH_KERNEL_DRIVER)) {
if (libusb_kernel_driver_active(usb->devhdl, 0) == 1) {