From: Oliver Neukum <oneukum@xxxxxxxx> commit 97fe809934dd2b0b37dfef3a2fc70417f485d7af upstream. If buffers are iterated over in the error case, the lower limits for quirky devices must be heeded. Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> Reported-by: Jean Rene Dawin <jdawin@xxxxxxxxxxxxxxxxxxxxx> Fixes: a4e7279cd1d19 ("cdc-acm: introduce a cool down") Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200526124420.22160-1-oneukum@xxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/class/cdc-acm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -590,7 +590,7 @@ static void acm_softint(struct work_stru } if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) { - for (i = 0; i < ACM_NR; i++) + for (i = 0; i < acm->rx_buflimit; i++) if (test_and_clear_bit(i, &acm->urbs_in_error_delay)) acm_submit_read_urb(acm, i, GFP_NOIO); }