Commit 9140fcd6 authored by Daeseok Youn's avatar Daeseok Youn Committed by Greg Kroah-Hartman
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staging: dgap: implement error handling in dgap_tty_register() 



- alloc_tty_driver() is deprecated so it is changed to
tty_alloc_driver()
- Pointers which are allocated by alloc_tty_driver() and kzalloc()
can be NULL so it need to check NULL for them.
- If one of those is failed, it need to add proper handler for
avoiding memory leak.
- If both of drivers are registered normally, and
then set TRUE to dgap_major_serial{print}_registered. If one
of drivers is failed to register, leave a default value as
FALSE.

Signed-off-by: default avatarDaeseok Youn <daeseok.youn@gmail.com>
Reviewed-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 02d9b1eb

drivers/staging/dgap/dgap.c

+33 −12
Original line number Diff line number Diff line
@@ -1210,9 +1210,11 @@ static int dgap_ms_sleep(ulong ms) 
 */

static int dgap_tty_register(struct board_t *brd)

{

	int rc = 0;

	int rc;



	brd->serial_driver = alloc_tty_driver(MAXPORTS);

	brd->serial_driver = tty_alloc_driver(MAXPORTS, 0);

	if (IS_ERR(brd->serial_driver))

		return PTR_ERR(brd->serial_driver);



	snprintf(brd->serial_name, MAXTTYNAMELEN, "tty_dgap_%d_",

		 brd->boardnum);
@@ -1231,8 +1233,10 @@ static int dgap_tty_register(struct board_t *brd) 
	/* The kernel wants space to store pointers to tty_structs */

	brd->serial_driver->ttys =

		kzalloc(MAXPORTS * sizeof(struct tty_struct *), GFP_KERNEL);

	if (!brd->serial_driver->ttys)

		return -ENOMEM;

	if (!brd->serial_driver->ttys) {

		rc = -ENOMEM;

		goto free_serial_drv;

	}



	/*

	 * Entry points for driver.  Called by the kernel from
@@ -1245,7 +1249,11 @@ static int dgap_tty_register(struct board_t *brd) 
	 * again, separately so we don't get the LD confused about what major

	 * we are when we get into the dgap_tty_open() routine.

	 */

	brd->print_driver = alloc_tty_driver(MAXPORTS);

	brd->print_driver = tty_alloc_driver(MAXPORTS, 0);

	if (IS_ERR(brd->print_driver)) {

		rc = PTR_ERR(brd->print_driver);

		goto free_serial_drv;

	}



	snprintf(brd->print_name, MAXTTYNAMELEN, "pr_dgap_%d_",

		 brd->boardnum);
@@ -1264,8 +1272,10 @@ static int dgap_tty_register(struct board_t *brd) 
	/* The kernel wants space to store pointers to tty_structs */

	brd->print_driver->ttys =

		kzalloc(MAXPORTS * sizeof(struct tty_struct *), GFP_KERNEL);

	if (!brd->print_driver->ttys)

		return -ENOMEM;

	if (!brd->print_driver->ttys) {

		rc = -ENOMEM;

		goto free_print_drv;

	}



	/*

	 * Entry points for driver.  Called by the kernel from
@@ -1276,19 +1286,30 @@ static int dgap_tty_register(struct board_t *brd) 
	/* Register tty devices */

	rc = tty_register_driver(brd->serial_driver);

	if (rc < 0)

		return rc;

	brd->dgap_major_serial_registered = TRUE;

	dgap_boards_by_major[brd->serial_driver->major] = brd;

	brd->dgap_serial_major = brd->serial_driver->major;

		goto free_print_drv;



	/* Register Transparent Print devices */

	rc = tty_register_driver(brd->print_driver);

	if (rc < 0)

		return rc;

		goto unregister_serial_drv;



	brd->dgap_major_serial_registered = TRUE;

	dgap_boards_by_major[brd->serial_driver->major] = brd;

	brd->dgap_serial_major = brd->serial_driver->major;



	brd->dgap_major_transparent_print_registered = TRUE;

	dgap_boards_by_major[brd->print_driver->major] = brd;

	brd->dgap_transparent_print_major = brd->print_driver->major;



	return 0;



unregister_serial_drv:

	tty_unregister_driver(brd->serial_driver);

free_print_drv:

	put_tty_driver(brd->print_driver);

free_serial_drv:

	put_tty_driver(brd->serial_driver);



	return rc;

}

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