From: Greg KH <gregkh@linuxfoundation.org>
To: Lee Yongjun <jun85566@gmail.com>
Cc: stern@rowland.harvard.edu, digidietze@draisberghof.de,
xiehongyu1@kylinos.cn, linux-usb@vger.kernel.org,
usb-storage@lists.one-eyed-alien.net,
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com,
syzbot+7317196294d50d6e55c3@syzkaller.appspotmail.com
Subject: Re: [PATCH] usb-storage: option_ms: bound probe-time bulk transfers
Date: Tue, 13 Oct 2026 18:18:37 +0200 [thread overview]
Message-ID: <2026101310-crier-december-be03@gregkh> (raw)
In-Reply-To: <20261013132033.4352-1-jun85566@gmail.com>
On Tue, Oct 13, 2026 at 10:20:33PM +0900, Lee Yongjun wrote:
> The Option device initialization path issues bulk transfers
> without a timeout. If a device does not complete a transfer,
> the USB hub worker can remain blocked while holding the device
> mutex, causing usb_device_read() to hang.
So a broken device?
> Use the timeout-aware bulk transfer helper for the transfers
> in option_inquiry() and option_rezero(). This bounds the wait
> for each probe-time transfer to 30 seconds.
That feels very long, are you sure that works well?
> Tested with the syzbot C reproducer under QEMU/KVM. The
> patched kernel repeatedly completed USB device initialization
> attempts after approximately 30 seconds without triggering
> the previously observed hung-task warning.
>
> This patch depends on Hongyu Xie's pending v3 series:
> https://lore.kernel.org/r/20261001123135.38831-1-xy521521@gmail.com/
This should go below the --- line and is why sashiko is confused.
> Fixes: 32ebbe7b6ad4 ("USB: usb-storage: add filter to "option_ms" to leave unrecognized devices alone")
> Reported-by: syzbot+7317196294d50d6e55c3@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=7317196294d50d6e55c3
> Assisted-by: LLM
>
> Signed-off-by: Lee Yongjun <jun85566@gmail.com>
No blank line above here is needed.
thanks,
greg k-h
prev parent reply other threads:[~2026-10-13 16:18 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-13 13:20 [PATCH] usb-storage: option_ms: bound probe-time bulk transfers Lee Yongjun
2026-10-13 13:27 ` sashiko-bot
2026-10-13 16:18 ` Greg KH [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2026101310-crier-december-be03@gregkh \
--to=gregkh@linuxfoundation.org \
--cc=digidietze@draisberghof.de \
--cc=jun85566@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=stern@rowland.harvard.edu \
--cc=syzbot+7317196294d50d6e55c3@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
--cc=usb-storage@lists.one-eyed-alien.net \
--cc=xiehongyu1@kylinos.cn \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox