Am Dienstag, den 22.09.2020, 09:05 +0200 schrieb Johan Hovold:
> The relevant commits are
>
> a2bfb4a346d2 ("USB: support for cdc-acm of single interface devices") (2009)
> fd5054c169d2 ("USB: cdc_acm: Fix oops when Droids MuIn LCD is connected") (2011)
> 403dff4e2c94 ("USB: cdc-acm: check for valid interfaces") (2014)
>
> Before Greg added the sanity checks in that last commit, a broken
> call-management descriptor referring to a non-existent interface would
> cause a NULL-pointer dereference.
Yes.
> The second commit, adding support for a specific device, didn't fix that
> problem generally
Yes
> and only worked around it for one device by hardcoding
> the data interface to match the control interface,
How do you know. It hardcoded the data interface. That it matches
the control interface is a guess.
> thereby falling back
> to the "combined-interface" probing you added in that first commit.
How do you know? They may or may not match.
Regards
Oliver
