>From 3acdda98e73a153a5fb32c2cd401d2dde1653b0a Mon Sep 17 00:00:00 2001 From: Daeseok Youn <daeseok.youn@xxxxxxxxx> Date: Fri, 25 Apr 2014 16:04:59 +0900 Subject: [PATCH] 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: Daeseok Youn <daeseok.youn@xxxxxxxxx> --- V2: rebased on staging-next branch drivers/staging/dgap/dgap.c | 49 +++++++++++++++++++++++++++++++++--------- 1 files changed, 38 insertions(+), 11 deletions(-) diff --git a/drivers/staging/dgap/dgap.c b/drivers/staging/dgap/dgap.c index d7cfc45..e4cb7aa 100644 --- a/drivers/staging/dgap/dgap.c +++ b/drivers/staging/dgap/dgap.c @@ -1212,7 +1212,9 @@ static int dgap_tty_register(struct board_t *brd) { int rc = 0; - 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_ttys; + } 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 @@ -1276,20 +1286,37 @@ 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_ttys; /* 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 rc; + +unregister_serial_drv: + tty_unregister_driver(brd->serial_driver); +free_print_ttys: + kfree(brd->print_driver->ttys); + brd->print_driver->ttys = NULL; +free_print_drv: + put_tty_driver(brd->print_driver); +free_serial_ttys: + kfree(brd->serial_driver->ttys); + brd->serial_driver->ttys = NULL; +free_serial_drv: + put_tty_driver(brd->serial_driver); + + return rc; } /* -- 1.7.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel