net: macb: zero the link settings taprio reads back

macb_taprio_setup_replace() calls phylink_ethtool_ksettings_get() with
an uninitialised kset, and kset is not only an out-parameter. On a
fixed link, or an in-band link with no PHY, phylink writes speed and
duplex only if kset->base.rate_matching already reads RATE_MATCH_NONE,
a field it never writes itself; in PHY mode before the PHY is attached
it writes port and supported and nothing more. Either way the speed
read back afterwards can be stack garbage. The ethtool core zeroes the
structure on every path into the op, which is why its callers never
see this; taprio is the only in-kernel caller passing its own variable.

Fixes: 89934dbf169e ("net: macb: Add TAPRIO traffic scheduling support")
Assisted-by: LLM
Signed-off-by: Aleksei Sviridkin <f@lex.la>
Link: https://patch.msgid.link/20260903123652.23900-2-f@lex.la
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

0 files changed, 0 insertions, 0 deletions