[PATCHv2 0/2] rr: nvme-pci: fix races and UAF
Casey Chen
cachen at purestorage.com
Wed Jul 7 14:14:30 PDT 2021
Found two bugs while power-cycling PCIe NVMe drive for hours:
- Races in nvme_setup_io_queues()
- UAF introduced by nvme_dev_remove_admin(), which is found
after fixing the races. Without fixing the races, the system
just crashes and cannot survive to reproduce the UAF.
The proposed fixes have been tested for several days for correctness.
0. Code baseline
Tag nvme-5.14-2021-06-08 of repo http://git.infradead.org/nvme.git
1. Testing method
while :; power off one drive;
sleep $((RANDOM%3)).$((RANDOM%10));
power on the same drive;
sleep $((RANDOM%3)).$((RANDOM%10));
done
2. Sample crash trace due to races in nvme_setup_io_queues()
(task ID shown after the timestamps)
[11668.533431][ T716] pcieport 0000:87:08.0: pciehp: Slot(402): Card present
...
[11668.681298][T251231] nvme nvme12: pci function 0000:8c:00.0
[11668.681354][T26714] nvme 0000:8c:00.0: enabling device (0100 -> 0102)
[11669.046119][ C31] pcieport 0000:87:08.0: pciehp: pending interrupts 0x0108 from Slot Status
[11669.046142][ T716] pcieport 0000:87:08.0: pciehp: Slot(402): Link Down
[11669.046146][ T716] pcieport 0000:87:08.0: pciehp: Slot(402): Card not present
[11669.046149][ T716] pcieport 0000:87:08.0: pciehp: pciehp_unconfigure_device: domain:bus:dev = 0000:8c:00
[11669.077428][ T716] ------------[ cut here ]------------
[11669.077431][ T716] kernel BUG at drivers/pci/msi.c:348!
[11669.077555][ T716] invalid opcode: 0000 [#1] SMP KASAN
[11669.077658][ T716] CPU: 31 PID: 716 Comm: irq/127-pciehp Not tainted 5.13.0-rc3+
[11669.078022][ T716] RIP: 0010:free_msi_irqs+0x28a/0x2d0
...
[11669.093982][ T716] Call Trace:
[11669.096850][ T716] pci_free_irq_vectors+0xe/0x20
[11669.099695][ T716] nvme_dev_disable+0x140/0x760 [nvme]
[11669.102503][ T716] ? _raw_spin_lock_irqsave+0x9c/0x100
[11669.105271][ T716] ? trace_hardirqs_on+0x2c/0xe0
[11669.107994][ T716] nvme_remove+0x191/0x1e0 [nvme]
[11669.110689][ T716] pci_device_remove+0x6b/0x110
[11669.113316][ T716] device_release_driver_internal+0x14f/0x280
[11669.115939][ T716] pci_stop_bus_device+0xcb/0x100
[11669.118515][ T716] pci_stop_and_remove_bus_device+0xe/0x20
[11669.121079][ T716] pciehp_unconfigure_device+0xfa/0x200
[11669.123597][ T716] ? pciehp_configure_device+0x1c0/0x1c0
[11669.126049][ T716] ? trace_hardirqs_on+0x2c/0xe0
[11669.128444][ T716] pciehp_disable_slot+0xc4/0x1a0
[11669.130771][ T716] ? pciehp_runtime_suspend+0x40/0x40
[11669.133054][ T716] ? __mutex_lock_slowpath+0x10/0x10
[11669.135289][ T716] ? trace_hardirqs_on+0x2c/0xe0
[11669.137462][ T716] pciehp_handle_presence_or_link_change+0x15c/0x4f0
[11669.139632][ T716] ? down_read+0x11f/0x1a0
[11669.141731][ T716] ? pciehp_handle_disable_request+0x80/0x80
[11669.143817][ T716] ? rwsem_down_read_slowpath+0x600/0x600
[11669.145851][ T716] ? __radix_tree_lookup+0xb2/0x130
[11669.147842][ T716] pciehp_ist+0x19d/0x1a0
[11669.149790][ T716] ? pciehp_set_indicators+0xe0/0xe0
[11669.151704][ T716] ? irq_finalize_oneshot.part.46+0x1d0/0x1d0
[11669.153588][ T716] irq_thread_fn+0x3f/0xa0
[11669.155407][ T716] irq_thread+0x195/0x290
[11669.157147][ T716] ? irq_thread_check_affinity.part.49+0xe0/0xe0
[11669.158883][ T716] ? _raw_read_lock_irq+0x50/0x50
[11669.160611][ T716] ? _raw_read_lock_irq+0x50/0x50
[11669.162320][ T716] ? irq_forced_thread_fn+0xf0/0xf0
[11669.164032][ T716] ? trace_hardirqs_on+0x2c/0xe0
[11669.165731][ T716] ? irq_thread_check_affinity.part.49+0xe0/0xe0
[11669.167461][ T716] kthread+0x1c8/0x1f0
[11669.169173][ T716] ? kthread_parkme+0x40/0x40
[11669.170883][ T716] ret_from_fork+0x22/0x30
3. KASAN report for the UAF introduced by nvme_dev_remove_admin()
(task ID is shown after the timestamp)
[18319.015748][T246989] nvme nvme13: pci function 0000:8c:00.0
[18319.015795][T215541] nvme 0000:8c:00.0: enabling device (0100 -> 0102)
[18319.369086][ C31] pcieport 0000:87:08.0: pciehp: pending interrupts 0x0108 from Slot Status
[18319.369107][ T716] pcieport 0000:87:08.0: pciehp: Slot(402): Link Down
[18319.369111][ T716] pcieport 0000:87:08.0: pciehp: Slot(402): Card not present
[18319.369116][ T716] pcieport 0000:87:08.0: pciehp: pciehp_unconfigure_device: domain:bus:dev = 0000:8c:00
[18320.452045][T215541] nvme nvme13: 88/0/0 default/read/poll queues
[18320.469475][T215541] nvme nvme13: failed to mark controller live state
[18320.469483][T215541] nvme nvme13: Removing after probe failure status: -19
[18320.551295][T215541] ==================================================================
[18320.551299][T215541] BUG: KASAN: use-after-free in __blk_mq_all_tag_iter+0x9c/0x3f0
[18320.551311][T215541] Read of size 4 at addr ffff888897904d04 by task kworker/u178:2/215541
[18320.551315][T215541]
[18320.551318][T215541] CPU: 86 PID: 215541 Comm: kworker/u178:2 Not tainted 5.13.0-rc3+
[18320.551327][T215541] Workqueue: nvme-reset-wq nvme_reset_work [nvme]
[18320.551339][T215541] Call Trace:
[18320.551343][T215541] dump_stack+0xa4/0xdb
[18320.551354][T215541] ? __blk_mq_all_tag_iter+0x9c/0x3f0
[18320.551359][T215541] print_address_description.constprop.10+0x3a/0x60
[18320.551366][T215541] ? __blk_mq_all_tag_iter+0x9c/0x3f0
[18320.551372][T215541] ? __blk_mq_all_tag_iter+0x9c/0x3f0
[18320.551377][T215541] ? blk_mq_update_nr_requests+0x2a0/0x2a0
[18320.551382][T215541] kasan_report.cold.15+0x7c/0xd8
[18320.551390][T215541] ? __blk_mq_all_tag_iter+0x9c/0x3f0
[18320.551395][T215541] __blk_mq_all_tag_iter+0x9c/0x3f0
[18320.551401][T215541] ? blk_mq_update_nr_requests+0x2a0/0x2a0
[18320.551407][T215541] ? bt_iter+0xf0/0xf0
[18320.551412][T215541] ? __blk_mq_all_tag_iter+0x2c9/0x3f0
[18320.551417][T215541] ? blk_mq_update_nr_requests+0x2a0/0x2a0
[18320.551422][T215541] ? bt_iter+0xf0/0xf0
[18320.551427][T215541] ? dev_printk_emit+0x95/0xbb
[18320.551436][T215541] blk_mq_tagset_busy_iter+0x75/0xa0
[18320.551441][T215541] ? blk_mq_update_nr_requests+0x2a0/0x2a0
[18320.551446][T215541] ? blk_mq_update_nr_requests+0x2a0/0x2a0
[18320.551451][T215541] blk_mq_tagset_wait_completed_request+0x86/0xc0
[18320.551457][T215541] ? blk_mq_tagset_busy_iter+0xa0/0xa0
[18320.551463][T215541] ? blk_mq_tagset_busy_iter+0x80/0xa0
[18320.551469][T215541] ? trace_event_raw_event_nvme_setup_cmd+0x2d0/0x2d0 [nvme_core]
[18320.551493][T215541] nvme_dev_disable+0x4f6/0x760 [nvme]
[18320.551502][T215541] ? trace_hardirqs_on+0x2c/0xe0
[18320.551510][T215541] nvme_reset_work+0x226/0x2060 [nvme]
[18320.551520][T215541] ? nvme_remove+0x1e0/0x1e0 [nvme]
[18320.551528][T215541] ? __update_load_avg_cfs_rq+0x1d8/0x550
[18320.551537][T215541] ? down_read+0x11f/0x1a0
[18320.551545][T215541] ? newidle_balance+0x444/0x690
[18320.551552][T215541] ? update_load_avg+0x626/0xbe0
[18320.551557][T215541] ? update_cfs_group+0x1e/0x150
[18320.551562][T215541] ? load_balance+0x11d0/0x11d0
[18320.551567][T215541] ? dequeue_entity+0x150/0x730
[18320.551573][T215541] ? nvme_irq_check+0x60/0x60 [nvme]
[18320.551581][T215541] ? finish_task_switch+0x101/0x3d0
[18320.551588][T215541] ? read_word_at_a_time+0xe/0x20
[18320.551594][T215541] ? strscpy+0xc1/0x1d0
[18320.551598][T215541] process_one_work+0x4b9/0x7b0
[18320.551604][T215541] worker_thread+0x72/0x710
[18320.551610][T215541] ? process_one_work+0x7b0/0x7b0
[18320.551614][T215541] kthread+0x1c8/0x1f0
[18320.551618][T215541] ? kthread_parkme+0x40/0x40
[18320.551622][T215541] ret_from_fork+0x22/0x30
[18320.551630][T215541]
[18320.551632][T215541] Allocated by task 215541:
[18320.551635][T215541] kasan_save_stack+0x19/0x40
[18320.551639][T215541] __kasan_kmalloc+0x7f/0xa0
[18320.551642][T215541] kmem_cache_alloc_node_trace+0x187/0x2b0
[18320.551648][T215541] blk_mq_init_tags+0x47/0x100
[18320.551651][T215541] blk_mq_alloc_rq_map+0x44/0xf0
[18320.551656][T215541] __blk_mq_alloc_map_and_request+0x7f/0x140
[18320.551661][T215541] blk_mq_alloc_tag_set+0x25e/0x510
[18320.551666][T215541] nvme_reset_work+0x14f9/0x2060 [nvme]
[18320.551674][T215541] process_one_work+0x4b9/0x7b0
[18320.551678][T215541] worker_thread+0x72/0x710
[18320.551682][T215541] kthread+0x1c8/0x1f0
[18320.551685][T215541] ret_from_fork+0x22/0x30
[18320.551689][T215541]
[18320.551690][T215541] Freed by task 716:
[18320.551693][T215541] kasan_save_stack+0x19/0x40
[18320.551696][T215541] kasan_set_track+0x1c/0x30
[18320.551699][T215541] kasan_set_free_info+0x20/0x30
[18320.551704][T215541] __kasan_slab_free+0xec/0x130
[18320.551707][T215541] kfree+0xa8/0x460
[18320.551712][T215541] blk_mq_free_map_and_requests+0x8d/0xc0
[18320.551717][T215541] blk_mq_free_tag_set+0x30/0xf0
[18320.551721][T215541] nvme_remove+0x199/0x1e0 [nvme]
[18320.551729][T215541] pci_device_remove+0x6b/0x110
[18320.551735][T215541] device_release_driver_internal+0x14f/0x280
[18320.551744][T215541] pci_stop_bus_device+0xcb/0x100
[18320.551750][T215541] pci_stop_and_remove_bus_device+0xe/0x20
[18320.551754][T215541] pciehp_unconfigure_device+0xfa/0x200
[18320.551761][T215541] pciehp_disable_slot+0xc4/0x1a0
[18320.551765][T215541] pciehp_handle_presence_or_link_change+0x15c/0x4f0
[18320.551770][T215541] pciehp_ist+0x19d/0x1a0
[18320.551774][T215541] irq_thread_fn+0x3f/0xa0
[18320.551780][T215541] irq_thread+0x195/0x290
[18320.551783][T215541] kthread+0x1c8/0x1f0
[18320.551786][T215541] ret_from_fork+0x22/0x30
[18320.551791][T215541]
[18320.551792][T215541] The buggy address belongs to the object at ffff888897904d00
[18320.551792][T215541] which belongs to the cache kmalloc-192 of size 192
[18320.551795][T215541] The buggy address is located 4 bytes inside of
[18320.551795][T215541] 192-byte region [ffff888897904d00, ffff888897904dc0)
[18320.551800][T215541] The buggy address belongs to the page:
[18320.551802][T215541] page:000000002f3df664 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x897904
[18320.551807][T215541] head:000000002f3df664 order:1 compound_mapcount:0
[18320.551810][T215541] flags: 0x200000000010200(slab|head|node=0|zone=2)
[18320.551819][T215541] raw: 0200000000010200 dead000000000100 dead000000000122 ffff88810004ca00
[18320.551824][T215541] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
[18320.551826][T215541] page dumped because: kasan: bad access detected
[18320.551828][T215541]
[18320.551829][T215541] Memory state around the buggy address:
[18320.551832][T215541] ffff888897904c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18320.551835][T215541] ffff888897904c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[18320.551838][T215541] >ffff888897904d00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18320.551841][T215541] ^
[18320.551843][T215541] ffff888897904d80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[18320.551846][T215541] ffff888897904e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[18320.551848][T215541] ==================================================================
[18320.551850][T215541] Disabling lock debugging due to kernel taint
Casey Chen (2):
nvme-pci: Fix multiple races in nvme_setup_io_queues()
nvme-pci: Fix UAF introduced by nvme_dev_remove_admin()
drivers/nvme/host/pci.c | 63 ++++++++++++++++++++++++++++++++++++-----
1 file changed, 56 insertions(+), 7 deletions(-)
--
2.17.1
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