diff options
Diffstat (limited to 'net/dsa/port.c')
| -rw-r--r-- | net/dsa/port.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/net/dsa/port.c b/net/dsa/port.c index 15cee17769e9..71ba30538411 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -114,19 +114,21 @@ static bool dsa_port_can_configure_learning(struct dsa_port *dp) return !err; } -bool dsa_port_supports_hwtstamp(struct dsa_port *dp, struct ifreq *ifr) +bool dsa_port_supports_hwtstamp(struct dsa_port *dp) { struct dsa_switch *ds = dp->ds; + struct ifreq ifr = {}; int err; if (!ds->ops->port_hwtstamp_get || !ds->ops->port_hwtstamp_set) return false; /* "See through" shim implementations of the "get" method. - * This will clobber the ifreq structure, but we will either return an - * error, or the master will overwrite it with proper values. + * Since we can't cook up a complete ioctl request structure, this will + * fail in copy_to_user() with -EFAULT, which hopefully is enough to + * detect a valid implementation. */ - err = ds->ops->port_hwtstamp_get(ds, dp->index, ifr); + err = ds->ops->port_hwtstamp_get(ds, dp->index, &ifr); return err != -EOPNOTSUPP; } |