From 9b788a678bed79cc167d3f16f8c9396ce67415e7 Mon Sep 17 00:00:00 2001 From: Zhang Enpei Date: Thu, 26 Jun 2025 17:28:23 +0800 Subject: [PATCH] USB: serial: mos7840: fix crash on resume commit 5ae6a64f18211851c8df6b4221381c438b9a7348 upstream. commit c15a688e49987385baa8804bf65d570e362f8576 upstream. Since commit c49cfa917025 ("USB: serial: use generic method if no alternative is provided in usb serial layer"), USB serial core calls the generic resume implementation when the driver has not provided one. This can trigger a crash on resume with mos7840 since support for multiple read URBs was added back in 2011. Specifically, both port read URBs are now submitted on resume for open ports, but the context pointer of the second URB is left set to the core rather than mos7840 port structure. Fix this by implementing dedicated suspend and resume functions for mos7840. Tested with Delock 87414 USB 2.0 to 4x serial adapter. Signed-off-by: Dmitry Smirnov [ johan: analyse crash and rewrite commit message; set busy flag on resume; drop bulk-in check; drop unnecessary usb_kill_urb() ] Fixes: d83b405383c9 ("USB: serial: add support for multiple read urbs") Cc: stable@vger.kernel.org # 3.3 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman Fixes: CVE-2024-42244 Signed-off-by: Enpei Zhang Signed-off-by: Wenya Zhang Reviewed-by: Xuexin Jiang --- drivers/usb/serial/mos7840.c | 45 ++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c index 8b0308d84270..85697466b147 100644 --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -1737,6 +1737,49 @@ static void mos7840_port_remove(struct usb_serial_port *port) kfree(mos7840_port); } +static int mos7840_suspend(struct usb_serial *serial, pm_message_t message) +{ + struct moschip_port *mos7840_port; + struct usb_serial_port *port; + int i; + + for (i = 0; i < serial->num_ports; ++i) { + port = serial->port[i]; + if (!tty_port_initialized(&port->port)) + continue; + + mos7840_port = usb_get_serial_port_data(port); + + usb_kill_urb(mos7840_port->read_urb); + mos7840_port->read_urb_busy = false; + } + + return 0; +} + +static int mos7840_resume(struct usb_serial *serial) +{ + struct moschip_port *mos7840_port; + struct usb_serial_port *port; + int res; + int i; + + for (i = 0; i < serial->num_ports; ++i) { + port = serial->port[i]; + if (!tty_port_initialized(&port->port)) + continue; + + mos7840_port = usb_get_serial_port_data(port); + + mos7840_port->read_urb_busy = true; + res = usb_submit_urb(mos7840_port->read_urb, GFP_NOIO); + if (res) + mos7840_port->read_urb_busy = false; + } + + return 0; +} + static struct usb_serial_driver moschip7840_4port_device = { .driver = { .owner = THIS_MODULE, @@ -1764,6 +1807,8 @@ static struct usb_serial_driver moschip7840_4port_device = { .port_probe = mos7840_port_probe, .port_remove = mos7840_port_remove, .read_bulk_callback = mos7840_bulk_in_callback, + .suspend = mos7840_suspend, + .resume = mos7840_resume, }; static struct usb_serial_driver * const serial_drivers[] = { -- Gitee