From: Oleksandr Natalenko <oleksandr@natalenko.name>
To: syzbot <syzbot+9b57a46bf1801ce2a2ca@syzkaller.appspotmail.com>,
Alan Stern <stern@rowland.harvard.edu>
Cc: benjamin.tissoires@redhat.com, jikos@kernel.org,
linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-usb@vger.kernel.org, mkubecek@suse.cz,
syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] WARNING in hid_submit_ctrl/usb_submit_urb
Date: Mon, 30 Aug 2021 21:22:39 +0200 [thread overview]
Message-ID: <2760703.iRigd37PT7@natalenko.name> (raw)
In-Reply-To: <20210819195300.GA8613@rowland.harvard.edu>
Hello.
On čtvrtek 19. srpna 2021 21:53:00 CEST Alan Stern wrote:
> On Thu, Aug 19, 2021 at 10:35:11AM -0700, syzbot wrote:
> > Hello,
> >
> > syzbot has tested the proposed patch but the reproducer is still
> > triggering an issue: WARNING in hid_submit_ctrl/usb_submit_urb
> >
> > cm6533_jd 0003:0D8C:0022.0001: submit_ctrl: maxpacket 64 len 0 padlen 0
> > ------------[ cut here ]------------
> > usb 1-1: BOGUS control dir, pipe 80000280 doesn't match bRequestType a1
>
> Ah. The padding code doesn't add anything if the length is
> already a multiple of the maxpacket value, and of course 0 is such
> a multiple.
>
> The following simplified variant of Michal's patch should fix the
> problem.
>
> Alan Stern
>
> #syz test:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> 794c7931a242
>
> Index: usb-devel/drivers/hid/usbhid/hid-core.c
> ===================================================================
> --- usb-devel.orig/drivers/hid/usbhid/hid-core.c
> +++ usb-devel/drivers/hid/usbhid/hid-core.c
> @@ -377,27 +377,23 @@ static int hid_submit_ctrl(struct hid_de
> len = hid_report_len(report);
> if (dir == USB_DIR_OUT) {
> usbhid->urbctrl->pipe = usb_sndctrlpipe(hid_to_usb_dev(hid),
0);
> - usbhid->urbctrl->transfer_buffer_length = len;
> if (raw_report) {
> memcpy(usbhid->ctrlbuf, raw_report, len);
> kfree(raw_report);
> usbhid->ctrl[usbhid->ctrltail].raw_report = NULL;
> }
> } else {
> - int maxpacket, padlen;
> + int maxpacket;
>
> usbhid->urbctrl->pipe = usb_rcvctrlpipe(hid_to_usb_dev(hid),
0);
> maxpacket = usb_maxpacket(hid_to_usb_dev(hid),
> usbhid->urbctrl->pipe, 0);
> - if (maxpacket > 0) {
> - padlen = DIV_ROUND_UP(len, maxpacket);
> - padlen *= maxpacket;
> - if (padlen > usbhid->bufsize)
> - padlen = usbhid->bufsize;
> - } else
> - padlen = 0;
> - usbhid->urbctrl->transfer_buffer_length = padlen;
> + len += (len == 0); /* Don't allow 0-length reports */
> + len = round_up(len, maxpacket);
> + if (len > usbhid->bufsize)
> + len = usbhid->bufsize;
> }
> + usbhid->urbctrl->transfer_buffer_length = len;
> usbhid->urbctrl->dev = hid_to_usb_dev(hid);
>
> usbhid->cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE | dir;
I've tried both Michal's patch as well as this one, and both work for me,
hence feel free to add this:
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
once the fix is submitted.
Thanks!
--
Oleksandr Natalenko (post-factum)
next prev parent reply other threads:[~2021-08-30 19:23 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-18 15:46 [syzbot] WARNING in hid_submit_ctrl/usb_submit_urb syzbot
2021-08-18 9:14 ` syzbot
2021-08-18 18:49 ` Alan Stern
2021-08-18 20:13 ` syzbot
2021-08-19 15:26 ` Alan Stern
2021-08-19 17:35 ` syzbot
2021-08-19 19:53 ` Alan Stern
2021-08-20 0:40 ` syzbot
2021-08-20 14:06 ` Alan Stern
2021-08-24 11:53 ` Jiri Kosina
2021-08-24 12:34 ` Benjamin Tissoires
2021-08-31 9:51 ` Benjamin Tissoires
2021-08-31 13:34 ` Alan Stern
2021-08-31 19:53 ` Jiri Kosina
2021-09-01 15:38 ` Alan Stern
2021-09-01 15:51 ` Michal Kubecek
2021-08-24 11:50 ` Michal Kubecek
2021-08-30 19:22 ` Oleksandr Natalenko [this message]
2021-08-18 19:01 ` Alan Stern
2021-08-18 19:39 ` syzbot
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=2760703.iRigd37PT7@natalenko.name \
--to=oleksandr@natalenko.name \
--cc=benjamin.tissoires@redhat.com \
--cc=jikos@kernel.org \
--cc=linux-input@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=mkubecek@suse.cz \
--cc=stern@rowland.harvard.edu \
--cc=syzbot+9b57a46bf1801ce2a2ca@syzkaller.appspotmail.com \
--cc=syzkaller-bugs@googlegroups.com \
/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;
as well as URLs for NNTP newsgroup(s).