[PATCH] misc: bcm-vk: fix tty registration race

From: Johan Hovold
Date: Fri Sep 17 2021 - 08:00:15 EST


Make sure to set the tty class-device driver data before registering the
tty to avoid having a racing open() dereference a NULL pointer.

Fixes: 91ca10d6fa07 ("misc: bcm-vk: add ttyVK support")
Cc: stable@xxxxxxxxxxxxxxx # 5.12
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
drivers/misc/bcm-vk/bcm_vk_tty.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/bcm-vk/bcm_vk_tty.c b/drivers/misc/bcm-vk/bcm_vk_tty.c
index 1b6076a89ca6..6669625ba4c8 100644
--- a/drivers/misc/bcm-vk/bcm_vk_tty.c
+++ b/drivers/misc/bcm-vk/bcm_vk_tty.c
@@ -267,13 +267,13 @@ int bcm_vk_tty_init(struct bcm_vk *vk, char *name)
struct device *tty_dev;

tty_port_init(&vk->tty[i].port);
- tty_dev = tty_port_register_device(&vk->tty[i].port, tty_drv,
- i, dev);
+ tty_dev = tty_port_register_device_attr(&vk->tty[i].port,
+ tty_drv, i, dev, vk,
+ NULL);
if (IS_ERR(tty_dev)) {
err = PTR_ERR(tty_dev);
goto unwind;
}
- dev_set_drvdata(tty_dev, vk);
vk->tty[i].is_opened = false;
}

--
2.32.0