| Message ID | 20210702142648.7677-2-ap420073@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: fix bonding ipsec offload problems | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | success | CCed 7 of 7 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 5 this patch: 5 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 26 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 5 this patch: 5 |
| netdev/header_inline | success | Link |
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 03b1a93d7fea..fd7b7f894917 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -403,10 +403,12 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs) struct net_device *bond_dev = xs->xso.dev; struct bonding *bond; struct slave *slave; + int err; if (!bond_dev) return -EINVAL; + rcu_read_lock(); bond = netdev_priv(bond_dev); slave = rcu_dereference(bond->curr_active_slave); xs->xso.real_dev = slave->dev; @@ -415,10 +417,13 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs) if (!(slave->dev->xfrmdev_ops && slave->dev->xfrmdev_ops->xdo_dev_state_add)) { slave_warn(bond_dev, slave->dev, "Slave does not support ipsec offload\n"); + rcu_read_unlock(); return -EINVAL; } - return slave->dev->xfrmdev_ops->xdo_dev_state_add(xs); + err = slave->dev->xfrmdev_ops->xdo_dev_state_add(xs); + rcu_read_unlock(); + return err; } /**
To dereference bond->curr_active_slave, it uses rcu_dereference(). But it and the caller doesn't acquire RCU so a warning occurs. So add rcu_read_lock(). Test commands: ip link add dummy0 type dummy ip link add bond0 type bond ip link set dummy0 master bond0 ip link set dummy0 up ip link set bond0 up ip x s add proto esp dst 14.1.1.1 src 15.1.1.1 spi 0x07 \ mode transport \ reqid 0x07 replay-window 32 aead 'rfc4106(gcm(aes))' \ 0x44434241343332312423222114131211f4f3f2f1 128 sel \ src 14.0.0.52/24 dst 14.0.0.70/24 proto tcp offload \ dev bond0 dir in Splat looks like: ============================= WARNING: suspicious RCU usage 5.13.0-rc3+ #1168 Not tainted ----------------------------- drivers/net/bonding/bond_main.c:411 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/684: #0: ffffffff9a2757c0 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{3:3}, at: xfrm_netlink_rcv+0x59/0x80 [xfrm_user] 55.191733][ T684] stack backtrace: CPU: 0 PID: 684 Comm: ip Not tainted 5.13.0-rc3+ #1168 Call Trace: dump_stack+0xa4/0xe5 bond_ipsec_add_sa+0x18c/0x1f0 [bonding] xfrm_dev_state_add+0x2a9/0x770 ? memcpy+0x38/0x60 xfrm_add_sa+0x2278/0x3b10 [xfrm_user] ? xfrm_get_policy+0xaa0/0xaa0 [xfrm_user] ? register_lock_class+0x1750/0x1750 xfrm_user_rcv_msg+0x331/0x660 [xfrm_user] ? rcu_read_lock_sched_held+0x91/0xc0 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? find_held_lock+0x3a/0x1c0 ? mutex_lock_io_nested+0x1210/0x1210 ? sched_clock_cpu+0x18/0x170 netlink_rcv_skb+0x121/0x350 ? xfrm_user_state_lookup.constprop.39+0x320/0x320 [xfrm_user] ? netlink_ack+0x9d0/0x9d0 ? netlink_deliver_tap+0x17c/0xa50 xfrm_netlink_rcv+0x68/0x80 [xfrm_user] netlink_unicast+0x41c/0x610 ? netlink_attachskb+0x710/0x710 netlink_sendmsg+0x6b9/0xb70 [ ... ] Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Taehee Yoo <ap420073@gmail.com> --- drivers/net/bonding/bond_main.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)