Re: [PATCH] fs: kernfs: fix possible null pointer dereferences

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, Apr 30, 2020 at 04:20:46AM -0700, youngjun wrote:
> kernfs_path_from_node_locked checks buf is NULL.
> But, two cases below are not covered.
> 
> if(!kn_to)			<--- case1 (buf can be NULL)
> 	return strlcpy(buf, "(null)", buflen);
> 
> if(kn_from == kn_to)		<--- case2 (buf can be NULL)
> 	return strlcpy(buf, "/", buflen);
> 
> if (!buf)			<--- checked here.
> 	return -EINVAL;
> 
> buf NULL case needs to be checked first.
> 
> Signed-off-by: youngjun <her0gyugyu@gmail.com>
> ---
>  fs/kernfs/dir.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

I have 3 patches here from you, with the same subject lines, yet they do
different things.

I'm dropping them all, can you please resend a patch series of the
remaining patches you wish us to review for kernfs?

thanks,

greg k-h