ppdev: Add an error check in register_device

In register_device, the return value of ida_simple_get is unchecked,
in witch ida_simple_get will use an invalid index value.

To address this issue, index should be checked after ida_simple_get. When
the index value is abnormal, a warning message should be printed, the port
should be dropped, and the value should be recorded.

Fixes: 9a69645dde ("ppdev: fix registering same device name")
Signed-off-by: Huai-Yuan Liu <qq810974084@gmail.com>
Link: https://lore.kernel.org/r/20240412083840.234085-1-qq810974084@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Huai-Yuan Liu 2024-04-12 16:38:40 +08:00 committed by Greg Kroah-Hartman
parent f866b65322
commit fbf740aeb8

View file

@ -296,28 +296,35 @@ static int register_device(int minor, struct pp_struct *pp)
if (!port) {
pr_warn("%s: no associated port!\n", name);
rc = -ENXIO;
goto err;
goto err_free_name;
}
index = ida_alloc(&ida_index, GFP_KERNEL);
if (index < 0) {
pr_warn("%s: failed to get index!\n", name);
rc = index;
goto err_put_port;
}
memset(&ppdev_cb, 0, sizeof(ppdev_cb));
ppdev_cb.irq_func = pp_irq;
ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
ppdev_cb.private = pp;
pdev = parport_register_dev_model(port, name, &ppdev_cb, index);
parport_put_port(port);
if (!pdev) {
pr_warn("%s: failed to register device!\n", name);
rc = -ENXIO;
ida_free(&ida_index, index);
goto err;
goto err_put_port;
}
pp->pdev = pdev;
pp->index = index;
dev_dbg(&pdev->dev, "registered pardevice\n");
err:
err_put_port:
parport_put_port(port);
err_free_name:
kfree(name);
return rc;
}