diff options
| author | Heitor Alves de Siqueira <halves@igalia.com> | 2026-05-05 15:56:03 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-05-22 10:36:06 +0200 |
| commit | 52f2ad3f7e5eb3b5908e1d685d4342519dc9cfcd (patch) | |
| tree | a16f3f9260109512756cc5eced526cc99d31af50 /drivers/usb/class | |
| parent | 5a4c828b8b29b47534814ade26d9aee09d5101fc (diff) | |
usb: usbtmc: check URB actual_length for interrupt-IN notifications
USBTMC devices can use an optional interrupt endpoint for notification
messages. These typically contain two-byte headers indicating the
payload format, but the driver does not check if these headers are
present before accessing the data buffers. In cases where the URB
actual_length is not enough to fit these headers, the driver will either
cause an out-of-bounds read, or consume stale leftover data from a
previous notification.
Fix by checking if actual_data contains enough bytes for the headers,
otherwise resubmit URB to the interrupt endpoint.
Fixes: dbf3e7f654c0 ("Implement an ioctl to support the USMTMC-USB488 READ_STATUS_BYTE operation.")
Reported-by: syzbot+abbfd103085885cf16a2@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=abbfd103085885cf16a2
Cc: stable <stable@kernel.org>
Suggested-by: Michal Pecio <michal.pecio@gmail.com>
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Link: https://patch.msgid.link/20260505-usbtmc-iin-size-v3-1-a36113f62db7@igalia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/class')
| -rw-r--r-- | drivers/usb/class/usbtmc.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index bd9347804dec..e15efd0c5ca7 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -2306,6 +2306,14 @@ static void usbtmc_interrupt(struct urb *urb) switch (status) { case 0: /* SUCCESS */ + /* ensure at least two bytes of headers were transferred */ + if (urb->actual_length < 2) { + dev_warn(dev, + "actual length %d not sufficient for interrupt headers\n", + urb->actual_length); + goto exit; + } + /* check for valid STB notification */ if (data->iin_buffer[0] > 0x81) { data->bNotify1 = data->iin_buffer[0]; |