Re: usb/core: warning in usb_create_ep_devs/sysfs_create_dir_ns

From: Alan Stern
Date: Mon Dec 12 2016 - 16:05:48 EST

On Mon, 12 Dec 2016, Andrey Konovalov wrote:

> Hi!
> While running the syzkaller fuzzer I've got the following error report.
> On commit 3c49de52d5647cda8b42c4255cf8a29d1e22eff5 (Dev 2).
> WARNING: CPU: 2 PID: 865 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x8a/0xa0
> gadgetfs: disconnected
> sysfs: cannot create duplicate filename
> '/devices/platform/dummy_hcd.0/usb2/2-1/2-1:64.0/ep_05'
> Kernel panic - not syncing: panic_on_warn set ...

I suppose we could check for USB devices that claim to have two
endpoints with the same address. But is it really worthwhile? A
kernel warning isn't so bad when you're dealing with buggy device

Alan Stern