Re: [PATCH 1/3] iio: pressure: bmp280: fix stack leak in bmp580 trigger handler

[David Lechner]

On 4/9/26 8:40 AM, Greg Kroah-Hartman wrote:
> bmp580_trigger_handler() declares its scan buffer on the stack without
> an initializer and then memcpy()s 3 bytes of 24-bit sensor data into
> each 4-byte __le32 field.  The high byte of comp_temp and comp_press is
> left uninitialized, and the channel storagebits is 32, so two bytes of
> stack are pushed to userspace per scan.
> 
> This is a regression from when the buffer lived in the private data, the
> move to a stack-local struct dropped the implicit zeroing.
> bme280_trigger_handler() was fixed up to handle this bug, but this
> driver was not fixed because there was no padding hole, but rather a
> short-fill issue.
> 
> Fix this all by just zero-initializing the structure on the stack.
> 

Reviewed-by: David Lechner <dlechner@xxxxxxxxxxxx>