From d9385b6352da7fed50981f375c2ccb60354039a6 Mon Sep 17 00:00:00 2001 From: Michal Nazarewicz Date: Thu, 28 Oct 2010 17:31:18 +0200 Subject: [PATCH] USB: gadget: file_storage: put_device() in error recovery This commit fixes some issues with File-backed Storage Gadget error recovery when registering LUN's devices. First of all, when device_register() fails the device still needs to be put. However, because lun_release() decreases fsg->ref reference counter the counter must be incremented beforehand. Second of all, after any of the device_create_file()s fails, device_unregister() is called which in turn (indirectly) calls lun_release() which decrements fsg->ref. So, again, the reference counter must be incremented beforehand. Lastly, if the first or the second device_create_file() succeeds, the files are never removed. To fix it, device_remove_file() needs to be called. This is done by simply marking LUN as registered prior to creating files so that fsg_unbind() can handle removing files. Signed-off-by: Michal Nazarewicz Reported-by: Rahul Ruikar Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/file_storage.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-) diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c index d4fdf65fb925..a6eacb59571b 100644 --- a/drivers/usb/gadget/file_storage.c +++ b/drivers/usb/gadget/file_storage.c @@ -3392,25 +3392,28 @@ static int __init fsg_bind(struct usb_gadget *gadget) dev_set_name(&curlun->dev,"%s-lun%d", dev_name(&gadget->dev), i); - if ((rc = device_register(&curlun->dev)) != 0) { + kref_get(&fsg->ref); + rc = device_register(&curlun->dev); + if (rc) { INFO(fsg, "failed to register LUN%d: %d\n", i, rc); - goto out; - } - if ((rc = device_create_file(&curlun->dev, - &dev_attr_ro)) != 0 || - (rc = device_create_file(&curlun->dev, - &dev_attr_nofua)) != 0 || - (rc = device_create_file(&curlun->dev, - &dev_attr_file)) != 0) { - device_unregister(&curlun->dev); + put_device(&curlun->dev); goto out; } curlun->registered = 1; - kref_get(&fsg->ref); + + rc = device_create_file(&curlun->dev, &dev_attr_ro); + if (rc) + goto out; + rc = device_create_file(&curlun->dev, &dev_attr_nofua); + if (rc) + goto out; + rc = device_create_file(&curlun->dev, &dev_attr_file); + if (rc) + goto out; if (mod_data.file[i] && *mod_data.file[i]) { - if ((rc = fsg_lun_open(curlun, - mod_data.file[i])) != 0) + rc = fsg_lun_open(curlun, mod_data.file[i]); + if (rc) goto out; } else if (!mod_data.removable) { ERROR(fsg, "no file given for LUN%d\n", i);