From 91fac0741d4817945c6ee0a17591421e7f5ecb86 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 7 Sep 2021 10:23:18 +0200 Subject: USB: cdc-acm: fix minor-number release If the driver runs out of minor numbers it would release minor 0 and allow another device to claim the minor while still in use. Fortunately, registering the tty class device of the second device would fail (with a stack dump) due to the sysfs name collision so no memory is leaked. Fixes: cae2bc768d17 ("usb: cdc-acm: Decrement tty port's refcount if probe() fail") Cc: stable@vger.kernel.org # 4.19 Cc: Jaejoong Kim Acked-by: Oliver Neukum Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210907082318.7757-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-acm.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/usb/class/cdc-acm.h') diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index 8aef5eb769a0..3aa7f0a3ad71 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -22,6 +22,8 @@ #define ACM_TTY_MAJOR 166 #define ACM_TTY_MINORS 256 +#define ACM_MINOR_INVALID ACM_TTY_MINORS + /* * Requests. */ -- cgit v1.2.3