diff options
| author | nikolay@redhat.com <nikolay@redhat.com> | 2013-05-18 01:18:28 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-05-19 23:25:49 -0700 |
| commit | ea6836dd7ef9cfbed5dce421190009f9eed00b7e (patch) | |
| tree | 3eb87d6856598772743b4fe8088468c7de09d8bb /drivers/net/bonding | |
| parent | ff0102ee104847023c36357e2b9f133f3f40d211 (diff) | |
| download | lwn-ea6836dd7ef9cfbed5dce421190009f9eed00b7e.tar.gz lwn-ea6836dd7ef9cfbed5dce421190009f9eed00b7e.zip | |
bonding: fix set mode race conditions
Changing the mode without any locking can result in multiple races (e.g.
upping a bond, enslaving/releasing). Depending on which race is hit the
impact can vary from incosistent bond state to kernel crash.
Use RTNL to synchronize the mode setting with the dangerous races.
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/bonding')
| -rw-r--r-- | drivers/net/bonding/bond_sysfs.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index ea7a388f4843..77ea237de900 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -316,6 +316,9 @@ static ssize_t bonding_store_mode(struct device *d, int new_value, ret = count; struct bonding *bond = to_bond(d); + if (!rtnl_trylock()) + return restart_syscall(); + if (bond->dev->flags & IFF_UP) { pr_err("unable to update mode of %s because interface is up.\n", bond->dev->name); @@ -352,6 +355,7 @@ static ssize_t bonding_store_mode(struct device *d, bond->dev->name, bond_mode_tbl[new_value].modename, new_value); out: + rtnl_unlock(); return ret; } static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR, |