| Message ID | 1389345523-5497-2-git-send-email-vfalico@redhat.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 2014/1/10 17:18, Veaceslav Falico wrote: > Currently, its usage is just plainly wrong. It first gets a slave under > RCU, and, after releasing the RCU lock, continues to use it - whilst it can > be freed. > > Fix this by ensuring that bond_3ad_set_carrier() holds RCU till it uses its > slave (or its agg). > > Fixes: be79bd048ab ("bonding: add RCU for bond_3ad_state_machine_handler()") > CC: dingtianhong@huawei.com > CC: Jay Vosburgh <fubar@us.ibm.com> > CC: Andy Gospodarek <andy@greyhouse.net> > Signed-off-by: Veaceslav Falico <vfalico@redhat.com> > --- > > Notes: > v2 -> v3: > Just wrap RCU for the whole usage of our slave. > > v1 -> v2: > Don't use _rcu primitives as we can be called under RTNL too. > > v1 -> v2: > Don't use _rcu primitives as we can be called under RTNL too. > > drivers/net/bonding/bond_3ad.c | 23 ++++++++++++----------- > 1 file changed, 12 insertions(+), 11 deletions(-) > > diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c > index 29db1ca..9ff55eb 100644 > --- a/drivers/net/bonding/bond_3ad.c > +++ b/drivers/net/bonding/bond_3ad.c > @@ -2327,32 +2327,33 @@ int bond_3ad_set_carrier(struct bonding *bond) > { > struct aggregator *active; > struct slave *first_slave; > + int ret = 1; > > rcu_read_lock(); > first_slave = bond_first_slave_rcu(bond); > - rcu_read_unlock(); > - if (!first_slave) > - return 0; > + if (!first_slave) { > + ret = 0; > + goto out; > + } > active = __get_active_agg(&(SLAVE_AD_INFO(first_slave).aggregator)); > if (active) { > /* are enough slaves available to consider link up? */ > if (active->num_of_ports < bond->params.min_links) { > if (netif_carrier_ok(bond->dev)) { > netif_carrier_off(bond->dev); > - return 1; > + goto out; > } > } else if (!netif_carrier_ok(bond->dev)) { > netif_carrier_on(bond->dev); > - return 1; > + goto out; > } > - return 0; > - } > - > - if (netif_carrier_ok(bond->dev)) { > + } else if (netif_carrier_ok(bond->dev)) { > netif_carrier_off(bond->dev); > - return 1; > + goto out; no need for this line, but it is not a big issue. Regards Ding > } > - return 0; > +out: > + rcu_read_unlock(); > + return ret; > } > > /** > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index 29db1ca..9ff55eb 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -2327,32 +2327,33 @@ int bond_3ad_set_carrier(struct bonding *bond) { struct aggregator *active; struct slave *first_slave; + int ret = 1; rcu_read_lock(); first_slave = bond_first_slave_rcu(bond); - rcu_read_unlock(); - if (!first_slave) - return 0; + if (!first_slave) { + ret = 0; + goto out; + } active = __get_active_agg(&(SLAVE_AD_INFO(first_slave).aggregator)); if (active) { /* are enough slaves available to consider link up? */ if (active->num_of_ports < bond->params.min_links) { if (netif_carrier_ok(bond->dev)) { netif_carrier_off(bond->dev); - return 1; + goto out; } } else if (!netif_carrier_ok(bond->dev)) { netif_carrier_on(bond->dev); - return 1; + goto out; } - return 0; - } - - if (netif_carrier_ok(bond->dev)) { + } else if (netif_carrier_ok(bond->dev)) { netif_carrier_off(bond->dev); - return 1; + goto out; } - return 0; +out: + rcu_read_unlock(); + return ret; } /**
Currently, its usage is just plainly wrong. It first gets a slave under RCU, and, after releasing the RCU lock, continues to use it - whilst it can be freed. Fix this by ensuring that bond_3ad_set_carrier() holds RCU till it uses its slave (or its agg). Fixes: be79bd048ab ("bonding: add RCU for bond_3ad_state_machine_handler()") CC: dingtianhong@huawei.com CC: Jay Vosburgh <fubar@us.ibm.com> CC: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> --- Notes: v2 -> v3: Just wrap RCU for the whole usage of our slave. v1 -> v2: Don't use _rcu primitives as we can be called under RTNL too. v1 -> v2: Don't use _rcu primitives as we can be called under RTNL too. drivers/net/bonding/bond_3ad.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)