On 5/2/20 7:40 PM, Jonathan Cameron wrote:
On Mon, 27 Apr 2020 20:06:07 +0200
Lars-Peter Clausen <lars@xxxxxxxxxx> wrote:
On 4/13/20 10:24 AM, Nuno Sá wrote:
[...]
+static irqreturn_t adis16475_trigger_handler(int irq, void *p)
+{
[...]
+ __be16 data[ADIS16475_MAX_SCAN_DATA], *buffer;
[...]
+
+ iio_push_to_buffers_with_timestamp(indio_dev, data, pf->timestamp);
If the timestamp is enabled the IIO core might insert padding between
the data channels and the timestamp. If that happens this will disclose
kernel stack memory to userspace.
This needs either a memset(data, 0x00, sizeof(data)) or maybe put data
into the state struct and kzalloc it.
Good spot. Could simply do __be16 data[ADI..] = {0}; rather than explicit
memset, but some form of zeroization is needed.
I've fixed up the applied patch with the above approach.
There is actually another issue. The stack data is not necessarily
aligned to 64 bit, which causes issues if we try to put the 64-bit
timestamp in it. I think data should really be in the state struct.
