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| author | Alan Stern <stern@rowland.harvard.edu> | 2021-09-01 19:36:00 +0300 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2021-09-01 21:52:31 +0300 |
| commit | 0a824efdb724e07574bafcd2c2486b2a3de35ff6 (patch) | |
| tree | 1b0db6fa8d983cb67b797336139cf8125e9f10b2 /drivers/hid/usbhid | |
| parent | 5049307d37a760e304ad191c5dc7c6851266d2f8 (diff) | |
| download | linux-0a824efdb724e07574bafcd2c2486b2a3de35ff6.tar.xz | |
HID: usbhid: Fix warning caused by 0-length input reports
Syzbot found a warning caused by hid_submit_ctrl() submitting a
control request to transfer a 0-length input report:
usb 1-1: BOGUS control dir, pipe 80000280 doesn't match bRequestType a1
(The warning message is a little difficult to understand. It means
that the control request claims to be for an IN transfer but this
contradicts the USB spec, which requires 0-length control transfers
always to be in the OUT direction.)
Now, a zero-length report isn't good for anything and there's no
reason for a device to have one, but the fuzzer likes to pick out
these weird edge cases. In the future, perhaps we will decide to
reject 0-length reports at probe time. For now, the simplest approach
for avoiding these warnings is to pretend that the report actually has
length 1.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: syzbot+9b57a46bf1801ce2a2ca@syzkaller.appspotmail.com
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'drivers/hid/usbhid')
| -rw-r--r-- | drivers/hid/usbhid/hid-core.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c index 6b8690878435..c56cb03c1551 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -389,6 +389,7 @@ static int hid_submit_ctrl(struct hid_device *hid) maxpacket = usb_maxpacket(hid_to_usb_dev(hid), usbhid->urbctrl->pipe, 0); if (maxpacket > 0) { + len += (len == 0); /* Don't allow 0-length reports */ len = DIV_ROUND_UP(len, maxpacket); len *= maxpacket; if (len > usbhid->bufsize) |