From ad9bd8daf2f9938572b0604e1280fefa8f338581 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Tue, 29 Oct 2019 09:12:32 +0000 Subject: [PATCH] bonding: fix using uninitialized mode_lock When a bonding interface is being created, it setups its mode and options. At that moment, it uses mode_lock so mode_lock should be initialized before that moment. rtnl_newlink() rtnl_create_link() alloc_netdev_mqs() ->setup() //bond_setup() ->newlink //bond_newlink bond_changelink() register_netdevice() ->ndo_init() //bond_init() After commit 089bca2caed0 ("bonding: use dynamic lockdep key instead of subclass"), mode_lock is initialized in bond_init(). So in the bond_changelink(), un-initialized mode_lock can be used. mode_lock should be initialized in bond_setup(). This patch partially reverts commit 089bca2caed0 ("bonding: use dynamic lockdep key instead of subclass") Test command: ip link add bond0 type bond mode 802.3ad lacp_rate 0 Splat looks like: [ 60.615127] INFO: trying to register non-static key. [ 60.615900] the code is fine but needs lockdep annotation. [ 60.616697] turning off the locking correctness validator. [ 60.617490] CPU: 1 PID: 957 Comm: ip Not tainted 5.4.0-rc3+ #109 [ 60.618350] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 60.619481] Call Trace: [ 60.619918] dump_stack+0x7c/0xbb [ 60.620453] register_lock_class+0x1215/0x14d0 [ 60.621131] ? alloc_netdev_mqs+0x7b3/0xcc0 [ 60.621771] ? is_bpf_text_address+0x86/0xf0 [ 60.622416] ? is_dynamic_key+0x230/0x230 [ 60.623032] ? unwind_get_return_address+0x5f/0xa0 [ 60.623757] ? create_prof_cpu_mask+0x20/0x20 [ 60.624408] ? arch_stack_walk+0x83/0xb0 [ 60.625023] __lock_acquire+0xd8/0x3de0 [ 60.625616] ? stack_trace_save+0x82/0xb0 [ 60.626225] ? stack_trace_consume_entry+0x160/0x160 [ 60.626957] ? deactivate_slab.isra.80+0x2c5/0x800 [ 60.627668] ? register_lock_class+0x14d0/0x14d0 [ 60.628380] ? alloc_netdev_mqs+0x7b3/0xcc0 [ 60.629020] ? save_stack+0x69/0x80 [ 60.629574] ? save_stack+0x19/0x80 [ 60.630121] ? __kasan_kmalloc.constprop.4+0xa0/0xd0 [ 60.630859] ? __kmalloc_node+0x16f/0x480 [ 60.631472] ? alloc_netdev_mqs+0x7b3/0xcc0 [ 60.632121] ? rtnl_create_link+0x2ed/0xad0 [ 60.634388] ? __rtnl_newlink+0xad4/0x11b0 [ 60.635024] lock_acquire+0x164/0x3b0 [ 60.635608] ? bond_3ad_update_lacp_rate+0x91/0x200 [bonding] [ 60.636463] _raw_spin_lock_bh+0x38/0x70 [ 60.637084] ? bond_3ad_update_lacp_rate+0x91/0x200 [bonding] [ 60.637930] bond_3ad_update_lacp_rate+0x91/0x200 [bonding] [ 60.638753] ? bond_3ad_lacpdu_recv+0xb30/0xb30 [bonding] [ 60.639552] ? bond_opt_get_val+0x180/0x180 [bonding] [ 60.640307] ? ___slab_alloc+0x5aa/0x610 [ 60.640925] bond_option_lacp_rate_set+0x71/0x140 [bonding] [ 60.641751] __bond_opt_set+0x1ff/0xbb0 [bonding] [ 60.643217] ? kasan_unpoison_shadow+0x30/0x40 [ 60.643924] bond_changelink+0x9a4/0x1700 [bonding] [ 60.644653] ? memset+0x1f/0x40 [ 60.742941] ? bond_slave_changelink+0x1a0/0x1a0 [bonding] [ 60.752694] ? alloc_netdev_mqs+0x8ea/0xcc0 [ 60.753330] ? rtnl_create_link+0x2ed/0xad0 [ 60.753964] bond_newlink+0x1e/0x60 [bonding] [ 60.754612] __rtnl_newlink+0xb9f/0x11b0 [ ... ] Reported-by: syzbot+8da67f407bcba2c72e6e@syzkaller.appspotmail.com Reported-by: syzbot+0d083911ab18b710da71@syzkaller.appspotmail.com Fixes: 089bca2caed0 ("bonding: use dynamic lockdep key instead of subclass") Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index a48950b81434..480f9459b402 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -4284,6 +4284,7 @@ void bond_setup(struct net_device *bond_dev) { struct bonding *bond = netdev_priv(bond_dev); + spin_lock_init(&bond->mode_lock); bond->params = bonding_defaults; /* Initialize pointers */ @@ -4756,7 +4757,6 @@ static int bond_init(struct net_device *bond_dev) if (!bond->wq) return -ENOMEM; - spin_lock_init(&bond->mode_lock); spin_lock_init(&bond->stats_lock); lockdep_register_key(&bond->stats_lock_key); lockdep_set_class(&bond->stats_lock, &bond->stats_lock_key);