serial: max310x: fix NULL pointer dereference in I2C instantiation

[ Upstream commit 0d27056c24 ]

When trying to instantiate a max14830 device from userspace:

    echo max14830 0x60 > /sys/bus/i2c/devices/i2c-2/new_device

we get the following error:

    Unable to handle kernel NULL pointer dereference at virtual address...
    ...
    Call trace:
        max310x_i2c_probe+0x48/0x170 [max310x]
        i2c_device_probe+0x150/0x2a0
    ...

Add check for validity of devtype to prevent the error, and abort probe
with a meaningful error message.

Fixes: 2e1f2d9a9b ("serial: max310x: implement I2C support")
Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20240118152213.2644269-2-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Hugo Villeneuve 2024-01-18 10:21:57 -05:00 committed by Greg Kroah-Hartman
parent 07c3fe923f
commit 12609c76b7
1 changed files with 5 additions and 2 deletions

View File

@ -1633,13 +1633,16 @@ static unsigned short max310x_i2c_slave_addr(unsigned short addr,
static int max310x_i2c_probe(struct i2c_client *client)
{
const struct max310x_devtype *devtype =
device_get_match_data(&client->dev);
const struct max310x_devtype *devtype;
struct i2c_client *port_client;
struct regmap *regmaps[4];
unsigned int i;
u8 port_addr;
devtype = device_get_match_data(&client->dev);
if (!devtype)
return dev_err_probe(&client->dev, -ENODEV, "Failed to match device\n");
if (client->addr < devtype->slave_addr.min ||
client->addr > devtype->slave_addr.max)
return dev_err_probe(&client->dev, -EINVAL,