This is a note to let you know that I've just added the patch titled
USB: console: fix potential use after free
to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-console-fix-potential-use-after-free.patch
and it can be found in the queue-3.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 32a4bf2e81ec378e5925d4e069e0677a6c86a6ad Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Mon, 5 Jan 2015 16:04:13 +0100
Subject: USB: console: fix potential use after free
From: Johan Hovold <johan@xxxxxxxxxx>
commit 32a4bf2e81ec378e5925d4e069e0677a6c86a6ad upstream.
Use tty kref to release the fake tty in usb_console_setup to avoid use
after free if the underlying serial driver has acquired a reference.
Note that using the tty destructor release_one_tty requires some more
state to be initialised.
Fixes: 4a90f09b20f4 ("tty: usb-serial krefs")
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/serial/console.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -46,6 +46,8 @@ static struct console usbcons;
* ------------------------------------------------------------
*/
+static const struct tty_operations usb_console_fake_tty_ops = {
+};
/*
* The parsing of the command line works exactly like the
@@ -137,14 +139,17 @@ static int usb_console_setup(struct cons
goto reset_open_count;
}
kref_init(&tty->kref);
- tty_port_tty_set(&port->port, tty);
tty->driver = usb_serial_tty_driver;
tty->index = co->index;
init_ldsem(&tty->ldisc_sem);
+ INIT_LIST_HEAD(&tty->tty_files);
+ kref_get(&tty->driver->kref);
+ tty->ops = &usb_console_fake_tty_ops;
if (tty_init_termios(tty)) {
retval = -ENOMEM;
- goto free_tty;
+ goto put_tty;
}
+ tty_port_tty_set(&port->port, tty);
}
/* only call the device specific open if this
@@ -162,7 +167,7 @@ static int usb_console_setup(struct cons
serial->type->set_termios(tty, port, &dummy);
tty_port_tty_set(&port->port, NULL);
- kfree(tty);
+ tty_kref_put(tty);
}
set_bit(ASYNCB_INITIALIZED, &port->port.flags);
}
@@ -178,8 +183,8 @@ static int usb_console_setup(struct cons
fail:
tty_port_tty_set(&port->port, NULL);
- free_tty:
- kfree(tty);
+ put_tty:
+ tty_kref_put(tty);
reset_open_count:
port->port.count = 0;
usb_autopm_put_interface(serial->interface);
Patches currently in stable-queue which might be from johan@xxxxxxxxxx are
queue-3.14/usb-console-fix-potential-use-after-free.patch
queue-3.14/usb-cp210x-add-ids-for-cel-usb-sticks-and-meshworks-devices.patch
queue-3.14/usb-keyspan-fix-null-deref-at-probe.patch
queue-3.14/usb-cp210x-fix-id-for-production-cel-meshconnect-usb-stick.patch
queue-3.14/gpio-fix-memory-and-reference-leaks-in-gpiochip_add-error-path.patch
queue-3.14/usb-console-fix-uninitialised-ldisc-semaphore.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html