[PATCH 5.4 51/90] net/mlx5e: Fix kernel crash when setting vf VLANID on a VF dev
From: Greg Kroah-Hartman
Date: Mon Aug 03 2020 - 08:28:51 EST
From: Alaa Hleihel <alaa@xxxxxxxxxxxx>
[ Upstream commit 350a63249d270b1f5bd05c7e2a24cd8de0f9db20 ]
After the cited commit, function 'mlx5_eswitch_set_vport_vlan' started
to acquire esw->state_lock.
However, esw is not defined for VF devices, hence attempting to set vf
VLANID on a VF dev will cause a kernel panic.
Fix it by moving up the (redundant) esw validation from function
'__mlx5_eswitch_set_vport_vlan' since the rest of the callers now have
and use a valid esw.
For example with vf device eth4:
# ip link set dev eth4 vf 0 vlan 0
Trace of the panic:
[ 411.409842] BUG: unable to handle page fault for address: 00000000000011b8
[ 411.449745] #PF: supervisor read access in kernel mode
[ 411.452348] #PF: error_code(0x0000) - not-present page
[ 411.454938] PGD 80000004189c9067 P4D 80000004189c9067 PUD 41899a067 PMD 0
[ 411.458382] Oops: 0000 [#1] SMP PTI
[ 411.460268] CPU: 4 PID: 5711 Comm: ip Not tainted 5.8.0-rc4_for_upstream_min_debug_2020_07_08_22_04 #1
[ 411.462447] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[ 411.464158] RIP: 0010:__mutex_lock+0x4e/0x940
[ 411.464928] Code: fd 41 54 49 89 f4 41 52 53 89 d3 48 83 ec 70 44 8b 1d ee 03 b0 01 65 48 8b 04 25 28 00 00 00 48 89 45 c8 31 c0 45 85 db 75 0a <48> 3b 7f 60 0f 85 7e 05 00 00 49 8d 45 68 41 56 41 b8 01 00 00 00
[ 411.467678] RSP: 0018:ffff88841fcd74b0 EFLAGS: 00010246
[ 411.468562] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 411.469715] RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000001158
[ 411.470812] RBP: ffff88841fcd7550 R08: ffffffffa00fa1ce R09: 0000000000000000
[ 411.471835] R10: ffff88841fcd7570 R11: 0000000000000000 R12: 0000000000000002
[ 411.472862] R13: 0000000000001158 R14: ffffffffa00fa1ce R15: 0000000000000000
[ 411.474004] FS: 00007faee7ca6b80(0000) GS:ffff88846fc00000(0000) knlGS:0000000000000000
[ 411.475237] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 411.476129] CR2: 00000000000011b8 CR3: 000000041909c006 CR4: 0000000000360ea0
[ 411.477260] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 411.478340] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 411.479332] Call Trace:
[ 411.479760] ? __nla_validate_parse.part.6+0x57/0x8f0
[ 411.482825] ? mlx5_eswitch_set_vport_vlan+0x3e/0xa0 [mlx5_core]
[ 411.483804] mlx5_eswitch_set_vport_vlan+0x3e/0xa0 [mlx5_core]
[ 411.484733] mlx5e_set_vf_vlan+0x41/0x50 [mlx5_core]
[ 411.485545] do_setlink+0x613/0x1000
[ 411.486165] __rtnl_newlink+0x53d/0x8c0
[ 411.486791] ? mark_held_locks+0x49/0x70
[ 411.487429] ? __lock_acquire+0x8fe/0x1eb0
[ 411.488085] ? rcu_read_lock_sched_held+0x52/0x60
[ 411.488998] ? kmem_cache_alloc_trace+0x16d/0x2d0
[ 411.489759] rtnl_newlink+0x47/0x70
[ 411.490357] rtnetlink_rcv_msg+0x24e/0x450
[ 411.490978] ? netlink_deliver_tap+0x92/0x3d0
[ 411.491631] ? validate_linkmsg+0x330/0x330
[ 411.492262] netlink_rcv_skb+0x47/0x110
[ 411.492852] netlink_unicast+0x1ac/0x270
[ 411.493551] netlink_sendmsg+0x336/0x450
[ 411.494209] sock_sendmsg+0x30/0x40
[ 411.494779] ____sys_sendmsg+0x1dd/0x1f0
[ 411.495378] ? copy_msghdr_from_user+0x5c/0x90
[ 411.496082] ___sys_sendmsg+0x87/0xd0
[ 411.496683] ? lock_acquire+0xb9/0x3a0
[ 411.497322] ? lru_cache_add+0x5/0x170
[ 411.497944] ? find_held_lock+0x2d/0x90
[ 411.498568] ? handle_mm_fault+0xe46/0x18c0
[ 411.499205] ? __sys_sendmsg+0x51/0x90
[ 411.499784] __sys_sendmsg+0x51/0x90
[ 411.500341] do_syscall_64+0x59/0x2e0
[ 411.500938] ? asm_exc_page_fault+0x8/0x30
[ 411.501609] ? rcu_read_lock_sched_held+0x52/0x60
[ 411.502350] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 411.503093] RIP: 0033:0x7faee73b85a7
[ 411.503654] Code: Bad RIP value.
Fixes: 0e18134f4f9f ("net/mlx5e: Eswitch, use state_lock to synchronize vlan change")
Signed-off-by: Alaa Hleihel <alaa@xxxxxxxxxxxx>
Reviewed-by: Roi Dayan <roid@xxxxxxxxxxxx>
Reviewed-by: Vlad Buslov <vladbu@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/eswitch.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index 6b711affb7da4..8e6ab82019398 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -2155,8 +2155,6 @@ int __mlx5_eswitch_set_vport_vlan(struct mlx5_eswitch *esw,
struct mlx5_vport *evport = mlx5_eswitch_get_vport(esw, vport);
int err = 0;
- if (!ESW_ALLOWED(esw))
- return -EPERM;
if (IS_ERR(evport))
return PTR_ERR(evport);
if (vlan > 4095 || qos > 7)
@@ -2184,6 +2182,9 @@ int mlx5_eswitch_set_vport_vlan(struct mlx5_eswitch *esw,
u8 set_flags = 0;
int err;
+ if (!ESW_ALLOWED(esw))
+ return -EPERM;
+
if (vlan || qos)
set_flags = SET_VLAN_STRIP | SET_VLAN_INSERT;
--
2.25.1