The debugfs_create_dir() and debugfs_create_file() functions may return -errno
if an error occurs. This patch adds a couple of checks of the result of the
debufs_create_dir() and debugfs_create_file() functions execution in the
hid_debug_register() and othre places.
Changelog:
v2:
* add check for the result of the debugfs_create_file() calls
* call hid_debug_init() and hid_debug_exit() only if hid_debug
* add check for the hid_debug_root in the hid_debug_register()
Signed-off-by: Alexander Kuleshov <[email protected]>
---
drivers/hid/hid-core.c | 15 ++++++++++-----
drivers/hid/hid-debug.c | 38 ++++++++++++++++++++++++++++++++++----
2 files changed, 44 insertions(+), 9 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index e6fce23..8aa2c20 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -2599,8 +2599,10 @@ int hid_add_device(struct hid_device *hdev)
ret = device_add(&hdev->dev);
if (!ret)
hdev->status |= HID_STAT_ADDED;
- else
- hid_debug_unregister(hdev);
+ else {
+ if (hdev->debug)
+ hid_debug_unregister(hdev);
+ }
return ret;
}
@@ -2644,7 +2646,8 @@ static void hid_remove_device(struct hid_device *hdev)
{
if (hdev->status & HID_STAT_ADDED) {
device_del(&hdev->dev);
- hid_debug_unregister(hdev);
+ if (hdev->debug)
+ hid_debug_unregister(hdev);
hdev->status &= ~HID_STAT_ADDED;
}
kfree(hdev->dev_rdesc);
@@ -2737,7 +2740,8 @@ static int __init hid_init(void)
if (ret)
goto err_bus;
- hid_debug_init();
+ if (hid_debug)
+ hid_debug_init();
return 0;
err_bus:
@@ -2748,7 +2752,8 @@ err:
static void __exit hid_exit(void)
{
- hid_debug_exit();
+ if (hid_debug)
+ hid_debug_exit();
hidraw_exit();
bus_unregister(&hid_bus_type);
}
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 2886b64..5db1e6e 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -1222,30 +1222,60 @@ static const struct file_operations hid_debug_events_fops = {
void hid_debug_register(struct hid_device *hdev, const char *name)
{
+ if (!hid_debug_root)
+ goto debugfs_root_error
+
hdev->debug_dir = debugfs_create_dir(name, hid_debug_root);
+
+ if (!hdev->debug_dir) {
+ printk(KERN_WARNING "Could not create '%s' debugfs directory\n",
+ name);
+ return;
+ }
+
hdev->debug_rdesc = debugfs_create_file("rdesc", 0400,
hdev->debug_dir, hdev, &hid_debug_rdesc_fops);
+ if (!hdev->debug_rdesc) {
+ printk(KERN_WARNING "Could not create rdesc debugfs file\n");
+ goto error
+ }
+
hdev->debug_events = debugfs_create_file("events", 0400,
hdev->debug_dir, hdev, &hid_debug_events_fops);
+ if (!hdev->debug_events) {
+ printk(KERN_WARNING "Could not create events debugfs file\n");
+ goto error
+ }
+
hdev->debug = 1;
+
+ return;
+
+error:
+ debugfs_remove_recursive(hdev->debug_dir);
+ return;
+
+debugfs_root_error:
+ return;
}
void hid_debug_unregister(struct hid_device *hdev)
{
hdev->debug = 0;
wake_up_interruptible(&hdev->debug_wait);
- debugfs_remove(hdev->debug_rdesc);
- debugfs_remove(hdev->debug_events);
- debugfs_remove(hdev->debug_dir);
+ debugfs_remove_recursive(hdev->debug_dir);
}
void hid_debug_init(void)
{
hid_debug_root = debugfs_create_dir("hid", NULL);
+ if (!hid_debug_root)
+ printk(KERN_WARNING "Could not create root 'hid' debugfs directory\n");
}
void hid_debug_exit(void)
{
- debugfs_remove_recursive(hid_debug_root);
+ if (hid_debug_root)
+ debugfs_remove_recursive(hid_debug_root);
}
--
2.5.0
On Wed, 19 Aug 2015, Alexander Kuleshov wrote:
> The debugfs_create_dir() and debugfs_create_file() functions may return -errno
> if an error occurs. This patch adds a couple of checks of the result of the
> debufs_create_dir() and debugfs_create_file() functions execution in the
> hid_debug_register() and othre places.
>
> Changelog:
>
> v2:
>
> * add check for the result of the debugfs_create_file() calls
> * call hid_debug_init() and hid_debug_exit() only if hid_debug
> * add check for the hid_debug_root in the hid_debug_register()
>
> Signed-off-by: Alexander Kuleshov <[email protected]>
> ---
> drivers/hid/hid-core.c | 15 ++++++++++-----
> drivers/hid/hid-debug.c | 38 ++++++++++++++++++++++++++++++++++----
> 2 files changed, 44 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> index e6fce23..8aa2c20 100644
> --- a/drivers/hid/hid-core.c
> +++ b/drivers/hid/hid-core.c
> @@ -2599,8 +2599,10 @@ int hid_add_device(struct hid_device *hdev)
> ret = device_add(&hdev->dev);
> if (!ret)
> hdev->status |= HID_STAT_ADDED;
> - else
> - hid_debug_unregister(hdev);
> + else {
> + if (hdev->debug)
> + hid_debug_unregister(hdev);
> + }
>
> return ret;
> }
> @@ -2644,7 +2646,8 @@ static void hid_remove_device(struct hid_device *hdev)
> {
> if (hdev->status & HID_STAT_ADDED) {
> device_del(&hdev->dev);
> - hid_debug_unregister(hdev);
> + if (hdev->debug)
> + hid_debug_unregister(hdev);
> hdev->status &= ~HID_STAT_ADDED;
> }
> kfree(hdev->dev_rdesc);
> @@ -2737,7 +2740,8 @@ static int __init hid_init(void)
> if (ret)
> goto err_bus;
>
> - hid_debug_init();
> + if (hid_debug)
> + hid_debug_init();
How is this change related to the rest of the patch?
It's wrong anyway, because hid_debug is independent of the debugfs HID
debugging facility. Please see for example the printk() a few lines above
in this very function, which is emited in case hid_debug is enabled.
--
Jiri Kosina
SUSE Labs
Hello Jiri,
On 08-19-15, Jiri Kosina wrote:
> On Wed, 19 Aug 2015, Alexander Kuleshov wrote:
>
> >
> > - hid_debug_init();
> > + if (hid_debug)
> > + hid_debug_init();
>
> How is this change related to the rest of the patch?
>
> It's wrong anyway, because hid_debug is independent of the debugfs HID
> debugging facility. Please see for example the printk() a few lines above
> in this very function, which is emited in case hid_debug is enabled.
>
hmm, I thought that these things are related. I've remove all hid_debug check
and sent v3 of the patch.