From ed1fe1bebe18884b11e5536b5ac42e3a48960835 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Fri, 11 Nov 2022 23:10:20 +0200 Subject: net: dsa: make dsa_master_ioctl() see through port_hwtstamp_get() shims MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There are multi-generational drivers like mv88e6xxx which have code like this: int mv88e6xxx_port_hwtstamp_get(struct dsa_switch *ds, int port, struct ifreq *ifr) { if (!chip->info->ptp_support) return -EOPNOTSUPP; ... } DSA wants to deny PTP timestamping on the master if the switch supports timestamping too. However it currently relies on the presence of the port_hwtstamp_get() callback to determine PTP capability, and this clearly does not work in that case (method is present but returns -EOPNOTSUPP). We should not deny PTP on the DSA master for those switches which truly do not support hardware timestamping. Create a dsa_port_supports_hwtstamp() method which actually probes for support by calling port_hwtstamp_get() and seeing whether that returned -EOPNOTSUPP or not. Fixes: f685e609a301 ("net: dsa: Deny PTP on master if switch supports it") Link: https://patchwork.kernel.org/project/netdevbpf/patch/20221110124345.3901389-1-festevam@gmail.com/ Reported-by: Fabio Estevam Reported-by: Steffen Bätz Signed-off-by: Vladimir Oltean Tested-by: Fabio Estevam Signed-off-by: David S. Miller --- net/dsa/dsa_priv.h | 1 + net/dsa/master.c | 3 +-- net/dsa/port.c | 16 ++++++++++++++++ 3 files changed, 18 insertions(+), 2 deletions(-) (limited to 'net/dsa') diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h index 6e65c7ffd6f3..71e9707d11d4 100644 --- a/net/dsa/dsa_priv.h +++ b/net/dsa/dsa_priv.h @@ -210,6 +210,7 @@ static inline struct net_device *dsa_master_find_slave(struct net_device *dev, extern struct rtnl_link_ops dsa_link_ops __read_mostly; /* port.c */ +bool dsa_port_supports_hwtstamp(struct dsa_port *dp, struct ifreq *ifr); void dsa_port_set_tag_protocol(struct dsa_port *cpu_dp, const struct dsa_device_ops *tag_ops); int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age); diff --git a/net/dsa/master.c b/net/dsa/master.c index 40367ab41cf8..421de166515f 100644 --- a/net/dsa/master.c +++ b/net/dsa/master.c @@ -204,8 +204,7 @@ static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) * switch in the tree that is PTP capable. */ list_for_each_entry(dp, &dst->ports, list) - if (dp->ds->ops->port_hwtstamp_get || - dp->ds->ops->port_hwtstamp_set) + if (dsa_port_supports_hwtstamp(dp, ifr)) return -EBUSY; break; } diff --git a/net/dsa/port.c b/net/dsa/port.c index 208168276995..750fe68d9b2a 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -110,6 +110,22 @@ 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) +{ + struct dsa_switch *ds = dp->ds; + 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. + */ + err = ds->ops->port_hwtstamp_get(ds, dp->index, ifr); + return err != -EOPNOTSUPP; +} + int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age) { struct dsa_switch *ds = dp->ds; -- cgit v1.2.3 From 4e0c19fcb8b5323716140fa82b79aa9f60e60407 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Mon, 14 Nov 2022 16:35:51 +0200 Subject: net: dsa: don't leak tagger-owned storage on switch driver unbind In the initial commit dc452a471dba ("net: dsa: introduce tagger-owned storage for private and shared data"), we had a call to tag_ops->disconnect(dst) issued from dsa_tree_free(), which is called at tree teardown time. There were problems with connecting to a switch tree as a whole, so this got reworked to connecting to individual switches within the tree. In this process, tag_ops->disconnect(ds) was made to be called only from switch.c (cross-chip notifiers emitted as a result of dynamic tag proto changes), but the normal driver teardown code path wasn't replaced with anything. Solve this problem by adding a function that does the opposite of dsa_switch_setup_tag_protocol(), which is called from the equivalent spot in dsa_switch_teardown(). The positioning here also ensures that we won't have any use-after-free in tagging protocol (*rcv) ops, since the teardown sequence is as follows: dsa_tree_teardown -> dsa_tree_teardown_master -> dsa_master_teardown -> unsets master->dsa_ptr, making no further packets match the ETH_P_XDSA packet type handler -> dsa_tree_teardown_ports -> dsa_port_teardown -> dsa_slave_destroy -> unregisters DSA net devices, there is even a synchronize_net() in unregister_netdevice_many() -> dsa_tree_teardown_switches -> dsa_switch_teardown -> dsa_switch_teardown_tag_protocol -> finally frees the tagger-owned storage Fixes: 7f2973149c22 ("net: dsa: make tagging protocols connect to individual switches from a tree") Signed-off-by: Vladimir Oltean Reviewed-by: Saeed Mahameed Reviewed-by: Florian Fainelli Link: https://lore.kernel.org/r/20221114143551.1906361-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski --- net/dsa/dsa2.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'net/dsa') diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c index e504a18fc125..5417f7b1187c 100644 --- a/net/dsa/dsa2.c +++ b/net/dsa/dsa2.c @@ -864,6 +864,14 @@ disconnect: return err; } +static void dsa_switch_teardown_tag_protocol(struct dsa_switch *ds) +{ + const struct dsa_device_ops *tag_ops = ds->dst->tag_ops; + + if (tag_ops->disconnect) + tag_ops->disconnect(ds); +} + static int dsa_switch_setup(struct dsa_switch *ds) { struct dsa_devlink_priv *dl_priv; @@ -953,6 +961,8 @@ static void dsa_switch_teardown(struct dsa_switch *ds) ds->slave_mii_bus = NULL; } + dsa_switch_teardown_tag_protocol(ds); + if (ds->ops->teardown) ds->ops->teardown(ds); -- cgit v1.2.3