iio: light: veml6030: fix IIO device retrieval from embedded device

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: iio: light: veml6030: fix IIO device retrieval from embedded device The dev pointer that is received as an argument in the in_illuminance_period_available_show function references the device embedded in the IIO device, not in the i2c client. dev_to_iio_dev() must be used to accessthe right data. The current implementation leads to a segmentation fault on every attempt to read the attribute because indio_dev gets a NULL assignment. This bug has been present since the first appearance of the driver, apparently since the last version (V6) before getting applied. A constant attribute was used until then, and the last modifications might have not been tested again.

References

• https://git.kernel.org/stable/c/bf3ab8e1c28f10df0823d4ff312f83c952b06a15
• https://git.kernel.org/stable/c/50039aec43a82ad2495f2d0fb0c289c8717b4bb2
• https://git.kernel.org/stable/c/bcb90518ccd9e10bf6ab29e31994aab93e4a4361
• https://git.kernel.org/stable/c/2cbb41abae65626736b8b52cf3b9339612c5a86a
• https://git.kernel.org/stable/c/905166531831beb067fffe2bdfc98031ffe89087
• https://git.kernel.org/stable/c/c7c44e57750c31de43906d97813273fdffcf7d02