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Date:   Sun, 3 Sep 2023 14:54:53 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Edward AD <eadavis@sina.com>
Cc:     syzbot+85792f3143e6271d2c97@syzkaller.appspotmail.com,
        andriy.shevchenko@linux.intel.com, linux-kernel@vger.kernel.org,
        rafael@kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: [PATCH] kobject: fix kobj and fmt are both null
Message-ID: <2023090328-slam-verbose-957d@gregkh>
References: <0000000000007b589e0604578e70@google.com>
 <20230903124231.3748101-1-eadavis@sina.com>
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On Sun, Sep 03, 2023 at 08:42:31PM +0800, Edward AD wrote:
> If kobj and fmt are both NULL, it will cause an exception in kvasprintf_const,
> then when this situation occurs, -EINVAL is directly returned.

How can this happen?  Are there any in-kernel users that cause this to
occur?

If so, which ones, why not fix that?

And your description isn't quite correct here, you are not checking for
kobj, but rather kobj->name.

thanks,

greg k-h