On 2021-08-13 15:54, Ben Greear wrote:

On 8/13/21 3:15 AM, Felix Fietkau wrote:

quoted

On 2021-07-31 04:17, Ryder Lee wrote:

quoted

From: Ben Greear <redacted>

Without this change, garbage is seen in the hwmon name
and sensors output for mt7915 is garbled.

Where does the use-after-free bug come from? It's not obvious to me why
using KBUILD_MODNAME instead of wiphy_name() fixes it.
I still think the phy name should probably be part of the prefix.

We rename phy devices as part of our normal operation, I think maybe
that helps trigger the bug.

It appears that the hwmon logic does not make a copy of the incoming string,
but instead just copies a char* and expects it to never go away.  But,
I did not actually verify that.

That makes sense. It seems that thermal copies the string internally,
but hwmon does not.
How about using devm_kstrdup on the wiphy name instead of using
KBUILD_MODNAME? If you really don't want to use the initial phy name,
there's also the option of using dev_name(dev->mt76.dev)

- Felix