Commit 0524513a authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

tty: don't store semi-state into tty drivers 



When a tty driver pointer is used as a return value of struct
console's device() hook, don't store a semi-state into global variable
which holds the tty driver. It could mean console::device() would return
a bogus value. This is important esp. after the next patch where we
switch from alloc_tty_driver to tty_alloc_driver. tty_alloc_driver
returns ERR_PTR in case of error and that might have unexpected results
as the code doesn't expect this.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Cc: Felipe Balbi <balbi@kernel.org>
Reviewed-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
Acked-by: Helge Deller <deller@gmx.de>	# parisc
Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210723074317.32690-4-jslaby@suse.cz


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7ccbdcc4

arch/m68k/emu/nfcon.c

+15 −12
Original line number Diff line number Diff line
@@ -120,35 +120,38 @@ early_param("debug", nf_debug_setup); 


static int __init nfcon_init(void)

{

	struct tty_driver *driver;

	int res;



	stderr_id = nf_get_id("NF_STDERR");

	if (!stderr_id)

		return -ENODEV;



	nfcon_tty_driver = alloc_tty_driver(1);

	if (!nfcon_tty_driver)

	driver = alloc_tty_driver(1);

	if (!driver)

		return -ENOMEM;



	tty_port_init(&nfcon_tty_port);



	nfcon_tty_driver->driver_name = "nfcon";

	nfcon_tty_driver->name = "nfcon";

	nfcon_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;

	nfcon_tty_driver->subtype = SYSTEM_TYPE_TTY;

	nfcon_tty_driver->init_termios = tty_std_termios;

	nfcon_tty_driver->flags = TTY_DRIVER_REAL_RAW;

	driver->driver_name = "nfcon";

	driver->name = "nfcon";

	driver->type = TTY_DRIVER_TYPE_SYSTEM;

	driver->subtype = SYSTEM_TYPE_TTY;

	driver->init_termios = tty_std_termios;

	driver->flags = TTY_DRIVER_REAL_RAW;



	tty_set_operations(nfcon_tty_driver, &nfcon_tty_ops);

	tty_port_link_device(&nfcon_tty_port, nfcon_tty_driver, 0);

	res = tty_register_driver(nfcon_tty_driver);

	tty_set_operations(driver, &nfcon_tty_ops);

	tty_port_link_device(&nfcon_tty_port, driver, 0);

	res = tty_register_driver(driver);

	if (res) {

		pr_err("failed to register nfcon tty driver\n");

		put_tty_driver(nfcon_tty_driver);

		put_tty_driver(driver);

		tty_port_destroy(&nfcon_tty_port);

		return res;

	}



	nfcon_tty_driver = driver;



	if (!(nf_console.flags & CON_ENABLED))

		register_console(&nf_console);

arch/parisc/kernel/pdc_cons.c

+15 −13
Original line number Diff line number Diff line
@@ -138,6 +138,7 @@ static struct tty_driver *pdc_console_tty_driver; 


static int __init pdc_console_tty_driver_init(void)

{

	struct tty_driver *driver;

	int err;



	/* Check if the console driver is still registered.
@@ -160,31 +161,32 @@ static int __init pdc_console_tty_driver_init(void) 
	printk(KERN_INFO "The PDC console driver is still registered, removing CON_BOOT flag\n");

	pdc_cons.flags &= ~CON_BOOT;



	pdc_console_tty_driver = alloc_tty_driver(1);



	if (!pdc_console_tty_driver)

	driver = alloc_tty_driver(1);

	if (!driver)

		return -ENOMEM;



	tty_port_init(&tty_port);



	pdc_console_tty_driver->driver_name = "pdc_cons";

	pdc_console_tty_driver->name = "ttyB";

	pdc_console_tty_driver->major = MUX_MAJOR;

	pdc_console_tty_driver->minor_start = 0;

	pdc_console_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;

	pdc_console_tty_driver->init_termios = tty_std_termios;

	pdc_console_tty_driver->flags = TTY_DRIVER_REAL_RAW |

	driver->driver_name = "pdc_cons";

	driver->name = "ttyB";

	driver->major = MUX_MAJOR;

	driver->minor_start = 0;

	driver->type = TTY_DRIVER_TYPE_SYSTEM;

	driver->init_termios = tty_std_termios;

	driver->flags = TTY_DRIVER_REAL_RAW |

		TTY_DRIVER_RESET_TERMIOS;

	tty_set_operations(pdc_console_tty_driver, &pdc_console_tty_ops);

	tty_port_link_device(&tty_port, pdc_console_tty_driver, 0);

	tty_set_operations(driver, &pdc_console_tty_ops);

	tty_port_link_device(&tty_port, driver, 0);



	err = tty_register_driver(pdc_console_tty_driver);

	err = tty_register_driver(driver);

	if (err) {

		printk(KERN_ERR "Unable to register the PDC console TTY driver\n");

		tty_port_destroy(&tty_port);

		return err;

	}



	pdc_console_tty_driver = driver;



	return 0;

}

device_initcall(pdc_console_tty_driver_init);

arch/xtensa/platforms/iss/console.c

+18 −15
Original line number Diff line number Diff line
@@ -136,39 +136,42 @@ static const struct tty_operations serial_ops = { 


static int __init rs_init(void)

{

	struct tty_driver *driver;

	int ret;



	serial_driver = alloc_tty_driver(SERIAL_MAX_NUM_LINES);

	if (!serial_driver)

	driver = alloc_tty_driver(SERIAL_MAX_NUM_LINES);

	if (!driver)

		return -ENOMEM;



	tty_port_init(&serial_port);



	/* Initialize the tty_driver structure */



	serial_driver->driver_name = "iss_serial";

	serial_driver->name = "ttyS";

	serial_driver->major = TTY_MAJOR;

	serial_driver->minor_start = 64;

	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;

	serial_driver->subtype = SERIAL_TYPE_NORMAL;

	serial_driver->init_termios = tty_std_termios;

	serial_driver->init_termios.c_cflag =

	driver->driver_name = "iss_serial";

	driver->name = "ttyS";

	driver->major = TTY_MAJOR;

	driver->minor_start = 64;

	driver->type = TTY_DRIVER_TYPE_SERIAL;

	driver->subtype = SERIAL_TYPE_NORMAL;

	driver->init_termios = tty_std_termios;

	driver->init_termios.c_cflag =

		B9600 | CS8 | CREAD | HUPCL | CLOCAL;

	serial_driver->flags = TTY_DRIVER_REAL_RAW;

	driver->flags = TTY_DRIVER_REAL_RAW;



	tty_set_operations(serial_driver, &serial_ops);

	tty_port_link_device(&serial_port, serial_driver, 0);

	tty_set_operations(driver, &serial_ops);

	tty_port_link_device(&serial_port, driver, 0);



	ret = tty_register_driver(serial_driver);

	ret = tty_register_driver(driver);

	if (ret) {

		pr_err("Couldn't register serial driver\n");

		tty_driver_kref_put(serial_driver);

		tty_driver_kref_put(driver);

		tty_port_destroy(&serial_port);



		return ret;

	}



	serial_driver = driver;



	return 0;

}

drivers/tty/amiserial.c

+19 −16
Original line number Diff line number Diff line
@@ -1490,34 +1490,35 @@ static const struct tty_port_operations amiga_port_ops = { 
static int __init amiga_serial_probe(struct platform_device *pdev)

{

	struct serial_state *state = &serial_state;

	struct tty_driver *driver;

	unsigned long flags;

	int error;



	serial_driver = alloc_tty_driver(1);

	if (!serial_driver)

	driver = alloc_tty_driver(1);

	if (!driver)

		return -ENOMEM;



	/* Initialize the tty_driver structure */



	serial_driver->driver_name = "amiserial";

	serial_driver->name = "ttyS";

	serial_driver->major = TTY_MAJOR;

	serial_driver->minor_start = 64;

	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;

	serial_driver->subtype = SERIAL_TYPE_NORMAL;

	serial_driver->init_termios = tty_std_termios;

	serial_driver->init_termios.c_cflag =

	driver->driver_name = "amiserial";

	driver->name = "ttyS";

	driver->major = TTY_MAJOR;

	driver->minor_start = 64;

	driver->type = TTY_DRIVER_TYPE_SERIAL;

	driver->subtype = SERIAL_TYPE_NORMAL;

	driver->init_termios = tty_std_termios;

	driver->init_termios.c_cflag =

		B9600 | CS8 | CREAD | HUPCL | CLOCAL;

	serial_driver->flags = TTY_DRIVER_REAL_RAW;

	tty_set_operations(serial_driver, &serial_ops);

	driver->flags = TTY_DRIVER_REAL_RAW;

	tty_set_operations(driver, &serial_ops);



	memset(state, 0, sizeof(*state));

	state->port = (int)&amiga_custom.serdatr; /* Just to give it a value */

	tty_port_init(&state->tport);

	state->tport.ops = &amiga_port_ops;

	tty_port_link_device(&state->tport, serial_driver, 0);

	tty_port_link_device(&state->tport, driver, 0);



	error = tty_register_driver(serial_driver);

	error = tty_register_driver(driver);

	if (error)

		goto fail_put_tty_driver;
@@ -1558,15 +1559,17 @@ static int __init amiga_serial_probe(struct platform_device *pdev) 


	platform_set_drvdata(pdev, state);



	serial_driver = driver;



	return 0;



fail_free_irq:

	free_irq(IRQ_AMIGA_TBE, state);

fail_unregister:

	tty_unregister_driver(serial_driver);

	tty_unregister_driver(driver);

fail_put_tty_driver:

	tty_port_destroy(&state->tport);

	put_tty_driver(serial_driver);

	put_tty_driver(driver);

	return error;

}

drivers/tty/ehv_bytechan.c

+16 −12
Original line number Diff line number Diff line
@@ -751,6 +751,7 @@ static struct platform_driver ehv_bc_tty_driver = { 
 */

static int __init ehv_bc_init(void)

{

	struct tty_driver *driver;

	struct device_node *np;

	unsigned int count = 0; /* Number of elements in bcs[] */

	int ret;
@@ -773,26 +774,28 @@ static int __init ehv_bc_init(void) 
	if (!bcs)

		return -ENOMEM;



	ehv_bc_driver = alloc_tty_driver(count);

	if (!ehv_bc_driver) {

	driver = alloc_tty_driver(count);

	if (!driver) {

		ret = -ENOMEM;

		goto err_free_bcs;

	}



	ehv_bc_driver->driver_name = "ehv-bc";

	ehv_bc_driver->name = ehv_bc_console.name;

	ehv_bc_driver->type = TTY_DRIVER_TYPE_CONSOLE;

	ehv_bc_driver->subtype = SYSTEM_TYPE_CONSOLE;

	ehv_bc_driver->init_termios = tty_std_termios;

	ehv_bc_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;

	tty_set_operations(ehv_bc_driver, &ehv_bc_ops);

	driver->driver_name = "ehv-bc";

	driver->name = ehv_bc_console.name;

	driver->type = TTY_DRIVER_TYPE_CONSOLE;

	driver->subtype = SYSTEM_TYPE_CONSOLE;

	driver->init_termios = tty_std_termios;

	driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;

	tty_set_operations(driver, &ehv_bc_ops);



	ret = tty_register_driver(ehv_bc_driver);

	ret = tty_register_driver(driver);

	if (ret) {

		pr_err("ehv-bc: could not register tty driver (ret=%i)\n", ret);

		goto err_put_tty_driver;

	}



	ehv_bc_driver = driver;



	ret = platform_driver_register(&ehv_bc_tty_driver);

	if (ret) {

		pr_err("ehv-bc: could not register platform driver (ret=%i)\n",
@@ -803,9 +806,10 @@ static int __init ehv_bc_init(void) 
	return 0;



err_deregister_tty_driver:

	tty_unregister_driver(ehv_bc_driver);

	ehv_bc_driver = NULL;

	tty_unregister_driver(driver);

err_put_tty_driver:

	put_tty_driver(ehv_bc_driver);

	put_tty_driver(driver);

err_free_bcs:

	kfree(bcs);