Re: [PATCH] usb: host: xhci_debugfs: Fix a null pointer dereference in xhci_debugfs_create_endpoint()

[Greg KH]

On Sat, May 04, 2019 at 11:37:48AM +0800, Jia-Ju Bai wrote:
> In xhci_debugfs_create_slot(), kzalloc() can fail and
> dev->debugfs_private will be NULL.
> In xhci_debugfs_create_endpoint(), dev->debugfs_private is used without
> any null-pointer check, and can cause a null pointer dereference.
> 
> To fix this bug, a null-pointer check is added in
> xhci_debugfs_create_endpoint().
> 
> This bug is found by a runtime fuzzing tool named FIZZER written by us.
> 
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>

Very rare case, but nice fix.  You should put "potential" in your
subject line as this is something that no one should ever hit :)

Anyway:

Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>