[PATCH] staging: dgnc: Fix a NULL pointer dereference

From: Daeseok Youn
Date: Wed May 04 2016 - 01:42:17 EST


The error handling for print_drive after calling tty_alloc_driver()
was needed. But there was error handling but too late for this.
Error handling code moved after tty_alloc_driver() call.

Fixes: 60b3109e5e2d ("staging: dgnc: use tty_alloc_driver instead of kcalloc")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Daeseok Youn <daeseok.youn@xxxxxxxxx>
---
drivers/staging/dgnc/dgnc_tty.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/dgnc/dgnc_tty.c b/drivers/staging/dgnc/dgnc_tty.c
index 2cecdb0..392d532 100644
--- a/drivers/staging/dgnc/dgnc_tty.c
+++ b/drivers/staging/dgnc/dgnc_tty.c
@@ -224,6 +224,11 @@ int dgnc_tty_register(struct dgnc_board *brd)
TTY_DRIVER_DYNAMIC_DEV |
TTY_DRIVER_HARDWARE_BREAK);

+ if (IS_ERR(brd->print_driver)) {
+ rc = PTR_ERR(brd->print_driver);
+ goto unregister_serial_driver;
+ }
+
snprintf(brd->print_name, MAXTTYNAMELEN, "pr_dgnc_%d_", brd->boardnum);

brd->print_driver->name = brd->print_name;
@@ -235,11 +240,6 @@ int dgnc_tty_register(struct dgnc_board *brd)
brd->print_driver->init_termios = DgncDefaultTermios;
brd->print_driver->driver_name = DRVSTR;

- if (IS_ERR(brd->print_driver)) {
- rc = PTR_ERR(brd->print_driver);
- goto unregister_serial_driver;
- }
-
/*
* Entry points for driver. Called by the kernel from
* tty_io.c and n_tty.c.
--
2.8.2