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extcon: Modify extcon device to be created after driver data is set

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Currently, someone can invoke the sysfs such as state_show()
intermittently before dev_set_drvdata() is done.
And it can be a cause of kernel Oops because of edev is Null at that time.
So modified the driver registration to after setting drviver data.

- Oops's backtrace.

Backtrace:
[<c067865c>] (state_show) from [<c05222e8>] (dev_attr_show)
[<c05222c0>] (dev_attr_show) from [<c02c66e0>] (sysfs_kf_seq_show)
[<c02c6648>] (sysfs_kf_seq_show) from [<c02c496c>] (kernfs_seq_show)
[<c02c4938>] (kernfs_seq_show) from [<c025e2a0>] (seq_read)
[<c025e11c>] (seq_read) from [<c02c50a0>] (kernfs_fop_read)
[<c02c5064>] (kernfs_fop_read) from [<c0231cac>] (__vfs_read)
[<c0231c5c>] (__vfs_read) from [<c0231ee0>] (vfs_read)
[<c0231e34>] (vfs_read) from [<c0232464>] (ksys_read)
[<c02323f0>] (ksys_read) from [<c02324fc>] (sys_read)
[<c02324e4>] (sys_read) from [<c00091d0>] (__sys_trace_return)

Signed-off-by: bumwoo lee <bw365.lee@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
This commit is contained in:
bumwoo lee 2022-04-27 12:00:05 +09:00 committed by Chanwoo Choi
parent 5faf7cbaff
commit 5dcc2afe71
1 changed files with 17 additions and 12 deletions
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29
drivers/extcon/extcon.c
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@ -1224,19 +1224,14 @@ int extcon_dev_register(struct extcon_dev *edev)
edev->dev.type = &edev->extcon_dev_type;
}
ret = device_register(&edev->dev);
if (ret) {
put_device(&edev->dev);
goto err_dev;
}
spin_lock_init(&edev->lock);
edev->nh = devm_kcalloc(&edev->dev, edev->max_supported,
sizeof(*edev->nh), GFP_KERNEL);
if (!edev->nh) {
ret = -ENOMEM;
device_unregister(&edev->dev);
goto err_dev;
if (edev->max_supported) {
edev->nh = kcalloc(edev->max_supported, sizeof(*edev->nh),
GFP_KERNEL);
if (!edev->nh) {
ret = -ENOMEM;
goto err_alloc_nh;
}
}
for (index = 0; index < edev->max_supported; index++)
@ -1247,6 +1242,12 @@ int extcon_dev_register(struct extcon_dev *edev)
dev_set_drvdata(&edev->dev, edev);
edev->state = 0;
ret = device_register(&edev->dev);
if (ret) {
put_device(&edev->dev);
goto err_dev;
}
mutex_lock(&extcon_dev_list_lock);
list_add(&edev->entry, &extcon_dev_list);
mutex_unlock(&extcon_dev_list_lock);
@ -1254,6 +1255,9 @@ int extcon_dev_register(struct extcon_dev *edev)
return 0;
err_dev:
if (edev->max_supported)
kfree(edev->nh);
err_alloc_nh:
if (edev->max_supported)
kfree(edev->extcon_dev_type.groups);
err_alloc_groups:
@ -1314,6 +1318,7 @@ void extcon_dev_unregister(struct extcon_dev *edev)
if (edev->max_supported) {
kfree(edev->extcon_dev_type.groups);
kfree(edev->cables);
kfree(edev->nh);
}
put_device(&edev->dev);