diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2018-05-07 19:10:31 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-06-26 08:08:07 +0800 |
| commit | 4f65ebcffa53ae01ffded87f83d92fd0caaafc5d (patch) | |
| tree | 9a58e970f6e96b66d4717f82d8eee8aeeddf8209 /drivers/base | |
| parent | e45ab2d6a89f9c31647efcb368a9c4378f2d76a9 (diff) | |
driver core: Don't ignore class_dir_create_and_add() failure.
commit 84d0c27d6233a9ba0578b20f5a09701eb66cee42 upstream.
syzbot is hitting WARN() at kernfs_add_one() [1].
This is because kernfs_create_link() is confused by previous device_add()
call which continued without setting dev->kobj.parent field when
get_device_parent() failed by memory allocation fault injection.
Fix this by propagating the error from class_dir_create_and_add() to
the calllers of get_device_parent().
[1] https://syzkaller.appspot.com/bug?id=fae0fb607989ea744526d1c082a5b8de6529116f
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+df47f81c226b31d89fb1@syzkaller.appspotmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/core.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index 03a82d017cf1..a0ed957d738f 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -759,7 +759,7 @@ class_dir_create_and_add(struct class *class, struct kobject *parent_kobj) dir = kzalloc(sizeof(*dir), GFP_KERNEL); if (!dir) - return NULL; + return ERR_PTR(-ENOMEM); dir->class = class; kobject_init(&dir->kobj, &class_dir_ktype); @@ -769,7 +769,7 @@ class_dir_create_and_add(struct class *class, struct kobject *parent_kobj) retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name); if (retval < 0) { kobject_put(&dir->kobj); - return NULL; + return ERR_PTR(retval); } return &dir->kobj; } @@ -1076,6 +1076,10 @@ int device_add(struct device *dev) parent = get_device(dev->parent); kobj = get_device_parent(dev, parent); + if (IS_ERR(kobj)) { + error = PTR_ERR(kobj); + goto parent_error; + } if (kobj) dev->kobj.parent = kobj; @@ -1174,6 +1178,7 @@ done: kobject_del(&dev->kobj); Error: cleanup_glue_dir(dev, glue_dir); +parent_error: put_device(parent); name_error: kfree(dev->p); @@ -1991,6 +1996,11 @@ int device_move(struct device *dev, struct device *new_parent, device_pm_lock(); new_parent = get_device(new_parent); new_parent_kobj = get_device_parent(dev, new_parent); + if (IS_ERR(new_parent_kobj)) { + error = PTR_ERR(new_parent_kobj); + put_device(new_parent); + goto out; + } pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev), __func__, new_parent ? dev_name(new_parent) : "<NULL>"); |