From 27e6f065df132b5270014d3285889b15185e9da9 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Tue, 5 Oct 2010 03:39:21 +0000 Subject: bonding: fix WARN_ON when writing to bond_master sysfs file Fix a WARN_ON failure in bond_masters sysfs file Got a report of this warning recently bonding: bond0 is being created... ------------[ cut here ]------------ WARNING: at fs/proc/generic.c:590 proc_register+0x14d/0x185() Hardware name: ProLiant BL465c G1 proc_dir_entry 'bonding/bond0' already registered Modules linked in: bonding ipv6 tg3 bnx2 shpchp amd64_edac_mod edac_core ipmi_si ipmi_msghandler serio_raw i2c_piix4 k8temp edac_mce_amd hpwdt microcode hpsa cc iss radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core [last unloaded: scsi_wai t_scan] Pid: 935, comm: ifup-eth Not tainted 2.6.33.5-124.fc13.x86_64 #1 Call Trace: [] warn_slowpath_common+0x77/0x8f [] warn_slowpath_fmt+0x3c/0x3e [] proc_register+0x14d/0x185 [] proc_create_data+0x87/0xa1 [] bond_create_proc_entry+0x55/0x95 [bonding] [] bond_init+0x95/0xd0 [bonding] [] register_netdevice+0xdd/0x29e [] bond_create+0x8e/0xb8 [bonding] [] bonding_store_bonds+0xb3/0x1c1 [bonding] [] class_attr_store+0x27/0x29 [] sysfs_write_file+0x10f/0x14b [] vfs_write+0xa9/0x106 [] sys_write+0x45/0x69 [] system_call_fastpath+0x16/0x1b ---[ end trace a677c3f7f8b16b1e ]--- bonding: Bond creation failed. It happens because a user space writer to bond_master can try to register an already existing bond interface name. Fix it by teaching bond_create to check for the existance of devices with that name first in cases where a non-NULL name parameter has been passed in Signed-off-by: Neil Horman Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 3b16f62d5606c7..e953c6ad6e6d1e 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -5164,6 +5164,15 @@ int bond_create(struct net *net, const char *name) res = dev_alloc_name(bond_dev, "bond%d"); if (res < 0) goto out; + } else { + /* + * If we're given a name to register + * we need to ensure that its not already + * registered + */ + res = -EEXIST; + if (__dev_get_by_name(net, name) != NULL) + goto out; } res = register_netdevice(bond_dev); -- cgit 1.2.3-korg