[PATCH 5.14 277/334] ice: Only lock to update netdev dev_addr

Greg Kroah-Hartman
2021-09-13T14:49:38Z

From: Brett Creeley <brett.creeley@intel.com>

[ Upstream commit b357d9717be7f95fde2c6c4650b186a995b71e59 ]

commit 3ba7f53f8bf1 ("ice: don't remove netdev->dev_addr from uc sync
list") introduced calls to netif_addr_lock_bh() and
netif_addr_unlock_bh() in the driver's ndo_set_mac() callback. This is
fine since the driver is updated the netdev's dev_addr, but since this
is a spinlock, the driver cannot sleep when the lock is held.
Unfortunately the functions to add/delete MAC filters depend on a mutex.
This was causing a trace with the lock debug kernel config options
enabled when changing the mac address via iproute.

[ 203.273059] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:281
[ 203.273065] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6698, name: ip
[ 203.273068] Preemption disabled at:
[ 203.273068] [<ffffffffc04aaeab>] ice_set_mac_address+0x8b/0x1c0 [ice]
[ 203.273097] CPU: 31 PID: 6698 Comm: ip Tainted: G S W I 5.14.0-rc4 #2
[ 203.273100] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0010.010620200716 01/06/2020
[ 203.273102] Call Trace:
[ 203.273107] dump_stack_lvl+0x33/0x42
[ 203.273113] ? ice_set_mac_address+0x8b/0x1c0 [ice]
[ 203.273124] ___might_sleep.cold.150+0xda/0xea
[ 203.273131] mutex_lock+0x1c/0x40
[ 203.273136] ice_remove_mac+0xe3/0x180 [ice]
[ 203.273155] ? ice_fltr_add_mac_list+0x20/0x20 [ice]
[ 203.273175] ice_fltr_prepare_mac+0x43/0xa0 [ice]
[ 203.273194] ice_set_mac_address+0xab/0x1c0 [ice]
[ 203.273206] dev_set_mac_address+0xb8/0x120
[ 203.273210] dev_set_mac_address_user+0x2c/0x50
[ 203.273212] do_setlink+0x1dd/0x10e0
[ 203.273217] ? __nla_validate_parse+0x12d/0x1a0
[ 203.273221] __rtnl_newlink+0x530/0x910
[ 203.273224] ? __kmalloc_node_track_caller+0x17f/0x380
[ 203.273230] ? preempt_count_add+0x68/0xa0
[ 203.273236] ? _raw_spin_lock_irqsave+0x1f/0x30
[ 203.273241] ? kmem_cache_alloc_trace+0x4d/0x440
[ 203.273244] rtnl_newlink+0x43/0x60
[ 203.273245] rtnetlink_rcv_msg+0x13a/0x380
[ 203.273248] ? rtnl_calcit.isra.40+0x130/0x130
[ 203.273250] netlink_rcv_skb+0x4e/0x100
[ 203.273256] netlink_unicast+0x1a2/0x280
[ 203.273258] netlink_sendmsg+0x242/0x490
[ 203.273260] sock_sendmsg+0x58/0x60
[ 203.273263] ____sys_sendmsg+0x1ef/0x260
[ 203.273265] ? copy_msghdr_from_user+0x5c/0x90
[ 203.273268] ? ____sys_recvmsg+0xe6/0x170
[ 203.273270] ___sys_sendmsg+0x7c/0xc0
[ 203.273272] ? copy_msghdr_from_user+0x5c/0x90
[ 203.273274] ? ___sys_recvmsg+0x89/0xc0
[ 203.273276] ? __netlink_sendskb+0x50/0x50
[ 203.273278] ? mod_objcg_state+0xee/0x310
[ 203.273282] ? __dentry_kill+0x114/0x170
[ 203.273286] ? get_max_files+0x10/0x10
[ 203.273288] __sys_sendmsg+0x57/0xa0
[ 203.273290] do_syscall_64+0x37/0x80
[ 203.273295] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 203.273296] RIP: 0033:0x7f8edf96e278
[ 203.273298] Code: 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 25 63 2c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 41 89 d4 55
[ 203.273300] RSP: 002b:00007ffcb8bdac08 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 203.273303] RAX: ffffffffffffffda RBX: 000000006115e0ae RCX: 00007f8edf96e278
[ 203.273304] RDX: 0000000000000000 RSI: 00007ffcb8bdac70 RDI: 0000000000000003
[ 203.273305] RBP: 0000000000000000 R08: 0000000000000001 R09: 00007ffcb8bda5b0
[ 203.273306] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
[ 203.273306] R13: 0000555e10092020 R14: 0000000000000000 R15: 0000000000000005

Fix this by only locking when changing the netdev->dev_addr. Also, make
sure to restore the old netdev->dev_addr on any failures.

Fixes: 3ba7f53f8bf1 ("ice: don't remove netdev->dev_addr from uc sync list")
Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/intel/ice/ice_main.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index fe2ded775f25..a8bd512d5b45 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -5122,6 +5122,7 @@ static int ice_set_mac_address(struct net_device *netdev, void *pi)
struct ice_hw *hw = &pf->hw;
struct sockaddr *addr = pi;
enum ice_status status;
+ u8 old_mac[ETH_ALEN];
u8 flags = 0;
int err = 0;
u8 *mac;
@@ -5144,8 +5145,13 @@ static int ice_set_mac_address(struct net_device *netdev, void *pi)
}

netif_addr_lock_bh(netdev);
+ ether_addr_copy(old_mac, netdev->dev_addr);
+ /* change the netdev's MAC address */
+ memcpy(netdev->dev_addr, mac, netdev->addr_len);
+ netif_addr_unlock_bh(netdev);
+
/* Clean up old MAC filter. Not an error if old filter doesn't exist */
- status = ice_fltr_remove_mac(vsi, netdev->dev_addr, ICE_FWD_TO_VSI);
+ status = ice_fltr_remove_mac(vsi, old_mac, ICE_FWD_TO_VSI);
if (status && status != ICE_ERR_DOES_NOT_EXIST) {
err = -EADDRNOTAVAIL;
goto err_update_filters;
@@ -5168,13 +5174,12 @@ err_update_filters:
if (err) {
netdev_err(netdev, "can't set MAC %pM. filter update failed\n",
mac);
+ netif_addr_lock_bh(netdev);
+ ether_addr_copy(netdev->dev_addr, old_mac);
netif_addr_unlock_bh(netdev);
return err;
}

- /* change the netdev's MAC address */
- memcpy(netdev->dev_addr, mac, netdev->addr_len);
- netif_addr_unlock_bh(netdev);
netdev_dbg(vsi->netdev, "updated MAC address to %pM\n",
netdev->dev_addr);

--
2.30.2