Re: [PATCH 6.1 5.15] net/mlx5: Free irqs only on shutdown callback

[Greg KH]

On Thu, Aug 03, 2023 at 07:28:32PM +0000, Hardik Garg wrote:
> commit 9c2d08010963 ("net/mlx5: Free irqs only on shutdown callback")
> backport this v6.4 commit to v6.1 and v5.15
> 
> 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 <fred@xxxxxxxxxxxxxx>
> Link: https://lore.kernel.org/netdev/be5b9271-7507-19c5-ded1-fa78f1980e69@xxxxxxxxxxxxxx
> Signed-off-by: Shay Drory <shayd@xxxxxxxxxx>
> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
> [hardik: Refer to the irqn member of the mlx5_irq struct, instead of
>  the msi_map, since we don't have upstream v6.4 commit 235a25fe28de
>  ("net/mlx5: Modify struct mlx5_irq to use struct msi_map")].
> [hardik: Refer to the pf_pool member of the mlx5_irq_table struct,
>  instead of pcif_pool, since we don't have upstream v6.4 commit
>  8bebfd767909 ("net/mlx5: Improve naming of pci function vectors")].

Now queued up, thanks.

greg k-h