mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

USB: serial: keyspan_pda: fix dropped unthrottle interrupts 

Commit c528fcb116 ("USB: serial: keyspan_pda: fix receive sanity
checks") broke write-unthrottle handling by dropping well-formed
unthrottle-interrupt packets which are precisely two bytes long. This
could lead to blocked writers not being woken up when buffer space again
becomes available.

Instead, stop unconditionally printing the third byte which is
(presumably) only valid on modem-line changes.

Fixes: c528fcb116 ("USB: serial: keyspan_pda: fix receive sanity checks")
Cc: stable <stable@vger.kernel.org>     # 4.11
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
This commit is contained in:
Johan Hovold 2020-10-25 18:45:47 +01:00
parent d1849b9ff9
commit 696c541c8c
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/usb/serial/keyspan_pda.c
View File

@ -172,11 +172,11 @@ static void keyspan_pda_rx_interrupt(struct urb *urb)
break;
case 1:
/* status interrupt */
if (len < 3) {
if (len < 2) {
dev_warn(&port->dev, "short interrupt message received\n");
break;
}
dev_dbg(&port->dev, "rx int, d1=%d, d2=%d\n", data[1], data[2]);
dev_dbg(&port->dev, "rx int, d1=%d\n", data[1]);
switch (data[1]) {
case 1: /* modemline change */
break;