From 2aeeef906d5a526dc60cf4af92eda69836c39b1f Mon Sep 17 00:00:00 2001 From: Jianbo Liu Date: Fri, 23 Aug 2024 06:10:56 +0300 Subject: [PATCH] bonding: change ipsec_lock from spin lock to mutex In the cited commit, bond->ipsec_lock is added to protect ipsec_list, hence xdo_dev_state_add and xdo_dev_state_delete are called inside this lock. As ipsec_lock is a spin lock and such xfrmdev ops may sleep, "scheduling while atomic" will be triggered when changing bond's active slave. [ 101.055189] BUG: scheduling while atomic: bash/902/0x00000200 [ 101.055726] Modules linked in: [ 101.058211] CPU: 3 PID: 902 Comm: bash Not tainted 6.9.0-rc4+ #1 [ 101.058760] Hardware name: [ 101.059434] Call Trace: [ 101.059436] [ 101.060873] dump_stack_lvl+0x51/0x60 [ 101.061275] __schedule_bug+0x4e/0x60 [ 101.061682] __schedule+0x612/0x7c0 [ 101.062078] ? __mod_timer+0x25c/0x370 [ 101.062486] schedule+0x25/0xd0 [ 101.062845] schedule_timeout+0x77/0xf0 [ 101.063265] ? asm_common_interrupt+0x22/0x40 [ 101.063724] ? __bpf_trace_itimer_state+0x10/0x10 [ 101.064215] __wait_for_common+0x87/0x190 [ 101.064648] ? usleep_range_state+0x90/0x90 [ 101.065091] cmd_exec+0x437/0xb20 [mlx5_core] [ 101.065569] mlx5_cmd_do+0x1e/0x40 [mlx5_core] [ 101.066051] mlx5_cmd_exec+0x18/0x30 [mlx5_core] [ 101.066552] mlx5_crypto_create_dek_key+0xea/0x120 [mlx5_core] [ 101.067163] ? bonding_sysfs_store_option+0x4d/0x80 [bonding] [ 101.067738] ? kmalloc_trace+0x4d/0x350 [ 101.068156] mlx5_ipsec_create_sa_ctx+0x33/0x100 [mlx5_core] [ 101.068747] mlx5e_xfrm_add_state+0x47b/0xaa0 [mlx5_core] [ 101.069312] bond_change_active_slave+0x392/0x900 [bonding] [ 101.069868] bond_option_active_slave_set+0x1c2/0x240 [bonding] [ 101.070454] __bond_opt_set+0xa6/0x430 [bonding] [ 101.070935] __bond_opt_set_notify+0x2f/0x90 [bonding] [ 101.071453] bond_opt_tryset_rtnl+0x72/0xb0 [bonding] [ 101.071965] bonding_sysfs_store_option+0x4d/0x80 [bonding] [ 101.072567] kernfs_fop_write_iter+0x10c/0x1a0 [ 101.073033] vfs_write+0x2d8/0x400 [ 101.073416] ? alloc_fd+0x48/0x180 [ 101.073798] ksys_write+0x5f/0xe0 [ 101.074175] do_syscall_64+0x52/0x110 [ 101.074576] entry_SYSCALL_64_after_hwframe+0x4b/0x53 As bond_ipsec_add_sa_all and bond_ipsec_del_sa_all are only called from bond_change_active_slave, which requires holding the RTNL lock. And bond_ipsec_add_sa and bond_ipsec_del_sa are xfrm state xdo_dev_state_add and xdo_dev_state_delete APIs, which are in user context. So ipsec_lock doesn't have to be spin lock, change it to mutex, and thus the above issue can be resolved. Fixes: 9a5605505d9c ("bonding: Add struct bond_ipesc to manage SA") Signed-off-by: Jianbo Liu Signed-off-by: Tariq Toukan Reviewed-by: Hangbin Liu Acked-by: Jay Vosburgh Link: https://patch.msgid.link/20240823031056.110999-4-jianbol@nvidia.com Signed-off-by: Jakub Kicinski --- drivers/net/bonding/bond_main.c | 79 ++++++++++++++++++--------------- include/net/bonding.h | 2 +- 2 files changed, 44 insertions(+), 37 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index f98491748420..bb9c3d6ef435 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -428,6 +428,7 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs, { struct net_device *bond_dev = xs->xso.dev; struct net_device *real_dev; + netdevice_tracker tracker; struct bond_ipsec *ipsec; struct bonding *bond; struct slave *slave; @@ -439,24 +440,26 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs, rcu_read_lock(); bond = netdev_priv(bond_dev); slave = rcu_dereference(bond->curr_active_slave); - if (!slave) { - rcu_read_unlock(); - return -ENODEV; + real_dev = slave ? slave->dev : NULL; + netdev_hold(real_dev, &tracker, GFP_ATOMIC); + rcu_read_unlock(); + if (!real_dev) { + err = -ENODEV; + goto out; } - real_dev = slave->dev; if (!real_dev->xfrmdev_ops || !real_dev->xfrmdev_ops->xdo_dev_state_add || netif_is_bond_master(real_dev)) { NL_SET_ERR_MSG_MOD(extack, "Slave does not support ipsec offload"); - rcu_read_unlock(); - return -EINVAL; + err = -EINVAL; + goto out; } - ipsec = kmalloc(sizeof(*ipsec), GFP_ATOMIC); + ipsec = kmalloc(sizeof(*ipsec), GFP_KERNEL); if (!ipsec) { - rcu_read_unlock(); - return -ENOMEM; + err = -ENOMEM; + goto out; } xs->xso.real_dev = real_dev; @@ -464,13 +467,14 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs, if (!err) { ipsec->xs = xs; INIT_LIST_HEAD(&ipsec->list); - spin_lock_bh(&bond->ipsec_lock); + mutex_lock(&bond->ipsec_lock); list_add(&ipsec->list, &bond->ipsec_list); - spin_unlock_bh(&bond->ipsec_lock); + mutex_unlock(&bond->ipsec_lock); } else { kfree(ipsec); } - rcu_read_unlock(); +out: + netdev_put(real_dev, &tracker); return err; } @@ -481,35 +485,35 @@ static void bond_ipsec_add_sa_all(struct bonding *bond) struct bond_ipsec *ipsec; struct slave *slave; - rcu_read_lock(); - slave = rcu_dereference(bond->curr_active_slave); - if (!slave) - goto out; + slave = rtnl_dereference(bond->curr_active_slave); + real_dev = slave ? slave->dev : NULL; + if (!real_dev) + return; - real_dev = slave->dev; + mutex_lock(&bond->ipsec_lock); if (!real_dev->xfrmdev_ops || !real_dev->xfrmdev_ops->xdo_dev_state_add || netif_is_bond_master(real_dev)) { - spin_lock_bh(&bond->ipsec_lock); if (!list_empty(&bond->ipsec_list)) slave_warn(bond_dev, real_dev, "%s: no slave xdo_dev_state_add\n", __func__); - spin_unlock_bh(&bond->ipsec_lock); goto out; } - spin_lock_bh(&bond->ipsec_lock); list_for_each_entry(ipsec, &bond->ipsec_list, list) { + /* If new state is added before ipsec_lock acquired */ + if (ipsec->xs->xso.real_dev == real_dev) + continue; + ipsec->xs->xso.real_dev = real_dev; if (real_dev->xfrmdev_ops->xdo_dev_state_add(ipsec->xs, NULL)) { slave_warn(bond_dev, real_dev, "%s: failed to add SA\n", __func__); ipsec->xs->xso.real_dev = NULL; } } - spin_unlock_bh(&bond->ipsec_lock); out: - rcu_read_unlock(); + mutex_unlock(&bond->ipsec_lock); } /** @@ -520,6 +524,7 @@ static void bond_ipsec_del_sa(struct xfrm_state *xs) { struct net_device *bond_dev = xs->xso.dev; struct net_device *real_dev; + netdevice_tracker tracker; struct bond_ipsec *ipsec; struct bonding *bond; struct slave *slave; @@ -530,6 +535,9 @@ static void bond_ipsec_del_sa(struct xfrm_state *xs) rcu_read_lock(); bond = netdev_priv(bond_dev); slave = rcu_dereference(bond->curr_active_slave); + real_dev = slave ? slave->dev : NULL; + netdev_hold(real_dev, &tracker, GFP_ATOMIC); + rcu_read_unlock(); if (!slave) goto out; @@ -537,7 +545,6 @@ static void bond_ipsec_del_sa(struct xfrm_state *xs) if (!xs->xso.real_dev) goto out; - real_dev = slave->dev; WARN_ON(xs->xso.real_dev != real_dev); if (!real_dev->xfrmdev_ops || @@ -549,7 +556,8 @@ static void bond_ipsec_del_sa(struct xfrm_state *xs) real_dev->xfrmdev_ops->xdo_dev_state_delete(xs); out: - spin_lock_bh(&bond->ipsec_lock); + netdev_put(real_dev, &tracker); + mutex_lock(&bond->ipsec_lock); list_for_each_entry(ipsec, &bond->ipsec_list, list) { if (ipsec->xs == xs) { list_del(&ipsec->list); @@ -557,8 +565,7 @@ out: break; } } - spin_unlock_bh(&bond->ipsec_lock); - rcu_read_unlock(); + mutex_unlock(&bond->ipsec_lock); } static void bond_ipsec_del_sa_all(struct bonding *bond) @@ -568,15 +575,12 @@ static void bond_ipsec_del_sa_all(struct bonding *bond) struct bond_ipsec *ipsec; struct slave *slave; - rcu_read_lock(); - slave = rcu_dereference(bond->curr_active_slave); - if (!slave) { - rcu_read_unlock(); + slave = rtnl_dereference(bond->curr_active_slave); + real_dev = slave ? slave->dev : NULL; + if (!real_dev) return; - } - real_dev = slave->dev; - spin_lock_bh(&bond->ipsec_lock); + mutex_lock(&bond->ipsec_lock); list_for_each_entry(ipsec, &bond->ipsec_list, list) { if (!ipsec->xs->xso.real_dev) continue; @@ -593,8 +597,7 @@ static void bond_ipsec_del_sa_all(struct bonding *bond) real_dev->xfrmdev_ops->xdo_dev_state_free(ipsec->xs); } } - spin_unlock_bh(&bond->ipsec_lock); - rcu_read_unlock(); + mutex_unlock(&bond->ipsec_lock); } static void bond_ipsec_free_sa(struct xfrm_state *xs) @@ -5921,7 +5924,7 @@ void bond_setup(struct net_device *bond_dev) /* set up xfrm device ops (only supported in active-backup right now) */ bond_dev->xfrmdev_ops = &bond_xfrmdev_ops; INIT_LIST_HEAD(&bond->ipsec_list); - spin_lock_init(&bond->ipsec_lock); + mutex_init(&bond->ipsec_lock); #endif /* CONFIG_XFRM_OFFLOAD */ /* don't acquire bond device's netif_tx_lock when transmitting */ @@ -5970,6 +5973,10 @@ static void bond_uninit(struct net_device *bond_dev) __bond_release_one(bond_dev, slave->dev, true, true); netdev_info(bond_dev, "Released all slaves\n"); +#ifdef CONFIG_XFRM_OFFLOAD + mutex_destroy(&bond->ipsec_lock); +#endif /* CONFIG_XFRM_OFFLOAD */ + bond_set_slave_arr(bond, NULL, NULL); list_del_rcu(&bond->bond_list); diff --git a/include/net/bonding.h b/include/net/bonding.h index b61fb1aa3a56..8bb5f016969f 100644 --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -260,7 +260,7 @@ struct bonding { #ifdef CONFIG_XFRM_OFFLOAD struct list_head ipsec_list; /* protecting ipsec_list */ - spinlock_t ipsec_lock; + struct mutex ipsec_lock; #endif /* CONFIG_XFRM_OFFLOAD */ struct bpf_prog *xdp_prog; };