Subject: [net 13/15] net/mlx5: Free irqs only on shutdown callback

From: Saeed Mahameed <[email-masked]>
Date: Mon, 22 May 2023 22:42:40 -0700

From: Shay Drory <[email-masked]>

Whenever a shutdown is invoked, free irqs only and keep mlx5_irq
synthetic wrapper intact in order to avoid use-after-free on
system shutdown.

for example:
==================================================================
BUG: KASAN: use-after-free in _find_first_bit+0x66/0x80
Read of size 8 at addr ffff88823fc0d318 by task kworker/u192:0/13608

CPU: 25 PID: 13608 Comm: kworker/u192:0 Tainted: G    B   W  O  6.1.21-cloudflare-kasan-2023.3.21 #1
Hardware name: GIGABYTE R162-R2-GEN0/MZ12-HD2-CD, BIOS R14 05/03/2021
Workqueue: mlx5e mlx5e_tx_timeout_work [mlx5_core]
Call Trace:
  <TASK>
  dump_stack_lvl+0x34/0x48
  print_report+0x170/0x473
  ? _find_first_bit+0x66/0x80
  kasan_report+0xad/0x130
  ? _find_first_bit+0x66/0x80
  _find_first_bit+0x66/0x80
  mlx5e_open_channels+0x3c5/0x3a10 [mlx5_core]
  ? console_unlock+0x2fa/0x430
  ? _raw_spin_lock_irqsave+0x8d/0xf0
  ? _raw_spin_unlock_irqrestore+0x42/0x80
  ? preempt_count_add+0x7d/0x150
  ? __wake_up_klogd.part.0+0x7d/0xc0
  ? vprintk_emit+0xfe/0x2c0
  ? mlx5e_trigger_napi_sched+0x40/0x40 [mlx5_core]
  ? dev_attr_show.cold+0x35/0x35
  ? devlink_health_do_dump.part.0+0x174/0x340
  ? devlink_health_report+0x504/0x810
  ? mlx5e_reporter_tx_timeout+0x29d/0x3a0 [mlx5_core]
  ? mlx5e_tx_timeout_work+0x17c/0x230 [mlx5_core]
  ? process_one_work+0x680/0x1050
  mlx5e_safe_switch_params+0x156/0x220 [mlx5_core]
  ? mlx5e_switch_priv_channels+0x310/0x310 [mlx5_core]
  ? mlx5_eq_poll_irq_disabled+0xb6/0x100 [mlx5_core]
  mlx5e_tx_reporter_timeout_recover+0x123/0x240 [mlx5_core]
  ? __mutex_unlock_slowpath.constprop.0+0x2b0/0x2b0
  devlink_health_reporter_recover+0xa6/0x1f0
  devlink_health_report+0x2f7/0x810
  ? vsnprintf+0x854/0x15e0
  mlx5e_reporter_tx_timeout+0x29d/0x3a0 [mlx5_core]
  ? mlx5e_reporter_tx_err_cqe+0x1a0/0x1a0 [mlx5_core]
  ? mlx5e_tx_reporter_timeout_dump+0x50/0x50 [mlx5_core]
  ? mlx5e_tx_reporter_dump_sq+0x260/0x260 [mlx5_core]
  ? newidle_balance+0x9b7/0xe30
  ? psi_group_change+0x6a7/0xb80
  ? mutex_lock+0x96/0xf0
  ? __mutex_lock_slowpath+0x10/0x10
  mlx5e_tx_timeout_work+0x17c/0x230 [mlx5_core]
  process_one_work+0x680/0x1050
  worker_thread+0x5a0/0xeb0
  ? process_one_work+0x1050/0x1050
  kthread+0x2a2/0x340
  ? kthread_complete_and_exit+0x20/0x20
  ret_from_fork+0x22/0x30
  </TASK>

Freed by task 1:
  kasan_save_stack+0x23/0x50
  kasan_set_track+0x21/0x30
  kasan_save_free_info+0x2a/0x40
  ____kasan_slab_free+0x169/0x1d0
  slab_free_freelist_hook+0xd2/0x190
  __kmem_cache_free+0x1a1/0x2f0
  irq_pool_free+0x138/0x200 [mlx5_core]
  mlx5_irq_table_destroy+0xf6/0x170 [mlx5_core]
  mlx5_core_eq_free_irqs+0x74/0xf0 [mlx5_core]
  shutdown+0x194/0x1aa [mlx5_core]
  pci_device_shutdown+0x75/0x120
  device_shutdown+0x35c/0x620
  kernel_restart+0x60/0xa0
  __do_sys_reboot+0x1cb/0x2c0
  do_syscall_64+0x3b/0x90
  entry_SYSCALL_64_after_hwframe+0x4b/0xb5

The buggy address belongs to the object at ffff88823fc0d300
  which belongs to the cache kmalloc-192 of size 192
The buggy address is located 24 bytes inside of
  192-byte region [ffff88823fc0d300, ffff88823fc0d3c0)

The buggy address belongs to the physical page:
page:0000000010139587 refcount:1 mapcount:0 mapping:0000000000000000
index:0x0 pfn:0x23fc0c
head:0000000010139587 order:1 compound_mapcount:0 compound_pincount:0
flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff)
raw: 002ffff800010200 0000000000000000 dead000000000122 ffff88810004ca00
raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff88823fc0d200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff88823fc0d280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 >ffff88823fc0d300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                             ^
  ffff88823fc0d380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
  ffff88823fc0d400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
general protection fault, probably for non-canonical address
0xdffffc005c40d7ac: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: probably user-memory-access in range [0x00000002e206bd60-0x00000002e206bd67]
CPU: 25 PID: 13608 Comm: kworker/u192:0 Tainted: G    B   W  O  6.1.21-cloudflare-kasan-2023.3.21 #1
Hardware name: GIGABYTE R162-R2-GEN0/MZ12-HD2-CD, BIOS R14 05/03/2021
Workqueue: mlx5e mlx5e_tx_timeout_work [mlx5_core]
RIP: 0010:__alloc_pages+0x141/0x5c0
Call Trace:
  <TASK>
  ? sysvec_apic_timer_interrupt+0xa0/0xc0
  ? asm_sysvec_apic_timer_interrupt+0x16/0x20
  ? __alloc_pages_slowpath.constprop.0+0x1ec0/0x1ec0
  ? _raw_spin_unlock_irqrestore+0x3d/0x80
  __kmalloc_large_node+0x80/0x120
  ? kvmalloc_node+0x4e/0x170
  __kmalloc_node+0xd4/0x150
  kvmalloc_node+0x4e/0x170
  mlx5e_open_channels+0x631/0x3a10 [mlx5_core]
  ? console_unlock+0x2fa/0x430
  ? _raw_spin_lock_irqsave+0x8d/0xf0
  ? _raw_spin_unlock_irqrestore+0x42/0x80
  ? preempt_count_add+0x7d/0x150
  ? __wake_up_klogd.part.0+0x7d/0xc0
  ? vprintk_emit+0xfe/0x2c0
  ? mlx5e_trigger_napi_sched+0x40/0x40 [mlx5_core]
  ? dev_attr_show.cold+0x35/0x35
  ? devlink_health_do_dump.part.0+0x174/0x340
  ? devlink_health_report+0x504/0x810
  ? mlx5e_reporter_tx_timeout+0x29d/0x3a0 [mlx5_core]
  ? mlx5e_tx_timeout_work+0x17c/0x230 [mlx5_core]
  ? process_one_work+0x680/0x1050
  mlx5e_safe_switch_params+0x156/0x220 [mlx5_core]
  ? mlx5e_switch_priv_channels+0x310/0x310 [mlx5_core]
  ? mlx5_eq_poll_irq_disabled+0xb6/0x100 [mlx5_core]
  mlx5e_tx_reporter_timeout_recover+0x123/0x240 [mlx5_core]
  ? __mutex_unlock_slowpath.constprop.0+0x2b0/0x2b0
  devlink_health_reporter_recover+0xa6/0x1f0
  devlink_health_report+0x2f7/0x810
  ? vsnprintf+0x854/0x15e0
  mlx5e_reporter_tx_timeout+0x29d/0x3a0 [mlx5_core]
  ? mlx5e_reporter_tx_err_cqe+0x1a0/0x1a0 [mlx5_core]
  ? mlx5e_tx_reporter_timeout_dump+0x50/0x50 [mlx5_core]
  ? mlx5e_tx_reporter_dump_sq+0x260/0x260 [mlx5_core]
  ? newidle_balance+0x9b7/0xe30
  ? psi_group_change+0x6a7/0xb80
  ? mutex_lock+0x96/0xf0
  ? __mutex_lock_slowpath+0x10/0x10
  mlx5e_tx_timeout_work+0x17c/0x230 [mlx5_core]
  process_one_work+0x680/0x1050
  worker_thread+0x5a0/0xeb0
  ? process_one_work+0x1050/0x1050
  kthread+0x2a2/0x340
  ? kthread_complete_and_exit+0x20/0x20
  ret_from_fork+0x22/0x30
  </TASK>
---[ end trace 0000000000000000  ]---
RIP: 0010:__alloc_pages+0x141/0x5c0
Code: e0 39 a3 96 89 e9 b8 22 01 32 01 83 e1 0f 48 89 fa 01 c9 48 c1 ea
03 d3 f8 83 e0 03 89 44 24 6c 48 b8 00 00 00 00 00 fc ff df <80> 3c 02
00 0f 85 fc 03 00 00 89 e8 4a 8b 14 f5 e0 39 a3 96 4c 89
RSP: 0018:ffff888251f0f438 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 1ffff1104a3e1e8b RCX: 0000000000000000
RDX: 000000005c40d7ac RSI: 0000000000000003 RDI: 00000002e206bd60
RBP: 0000000000052dc0 R08: ffff8882b0044218 R09: ffff8882b0045e8a
R10: fffffbfff300fefc R11: ffff888167af4000 R12: 0000000000000003
R13: 0000000000000000 R14: 00000000696c7070 R15: ffff8882373f4380
FS:  0000000000000000(0000) GS:ffff88bf2be80000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005641d031eee8 CR3: 0000002e7ca14000 CR4: 0000000000350ee0
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x11000000 from 0xffffffff81000000 (relocation range:
0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception  ]---]

Reported-by: Frederick Lawler <[email-masked]>
Link: https://lore.kernel.org/netdev/[email-masked]
Signed-off-by: Shay Drory <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/eq.c  |  2 +-
 .../ethernet/mellanox/mlx5/core/mlx5_irq.h    |  1 +
 .../net/ethernet/mellanox/mlx5/core/pci_irq.c | 29 +++++++++++++++++++
 3 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eq.c b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
index 1c35d721a31d..fe698c79616c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
@@ -1104,7 +1104,7 @@ void mlx5_core_eq_free_irqs(struct mlx5_core_dev *dev)
 	struct mlx5_eq_table *table = dev->priv.eq_table;
 
 	mutex_lock(&table->lock); /* sync with create/destroy_async_eq */
-	mlx5_irq_table_destroy(dev);
+	mlx5_irq_table_free_irqs(dev);
 	mutex_unlock(&table->lock);
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/mlx5_irq.h b/drivers/net/ethernet/mellanox/mlx5/core/mlx5_irq.h
index efd0c299c5c7..aa403a5ea34e 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/mlx5_irq.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/mlx5_irq.h
@@ -15,6 +15,7 @@ int mlx5_irq_table_init(struct mlx5_core_dev *dev);
 void mlx5_irq_table_cleanup(struct mlx5_core_dev *dev);
 int mlx5_irq_table_create(struct mlx5_core_dev *dev);
 void mlx5_irq_table_destroy(struct mlx5_core_dev *dev);
+void mlx5_irq_table_free_irqs(struct mlx5_core_dev *dev);
 int mlx5_irq_table_get_num_comp(struct mlx5_irq_table *table);
 int mlx5_irq_table_get_sfs_vec(struct mlx5_irq_table *table);
 struct mlx5_irq_table *mlx5_irq_table_get(struct mlx5_core_dev *dev);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c b/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
index 2245d3b2f393..ac1304c2d205 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
@@ -691,6 +691,24 @@ static void irq_pools_destroy(struct mlx5_irq_table *table)
 	irq_pool_free(table->pcif_pool);
 }
 
+static void mlx5_irq_pool_free_irqs(struct mlx5_irq_pool *pool)
+{
+	struct mlx5_irq *irq;
+	unsigned long index;
+
+	xa_for_each(&pool->irqs, index, irq)
+		free_irq(irq->map.virq, &irq->nh);
+}
+
+static void mlx5_irq_pools_free_irqs(struct mlx5_irq_table *table)
+{
+	if (table->sf_ctrl_pool) {
+		mlx5_irq_pool_free_irqs(table->sf_comp_pool);
+		mlx5_irq_pool_free_irqs(table->sf_ctrl_pool);
+	}
+	mlx5_irq_pool_free_irqs(table->pcif_pool);
+}
+
 /* irq_table API */
 
 int mlx5_irq_table_init(struct mlx5_core_dev *dev)
@@ -774,6 +792,17 @@ void mlx5_irq_table_destroy(struct mlx5_core_dev *dev)
 	pci_free_irq_vectors(dev->pdev);
 }
 
+void mlx5_irq_table_free_irqs(struct mlx5_core_dev *dev)
+{
+	struct mlx5_irq_table *table = dev->priv.irq_table;
+
+	if (mlx5_core_is_sf(dev))
+		return;
+
+	mlx5_irq_pools_free_irqs(table);
+	pci_free_irq_vectors(dev->pdev);
+}
+
 int mlx5_irq_table_get_sfs_vec(struct mlx5_irq_table *table)
 {
 	if (table->sf_comp_pool)
-- 
2.40.1