================================================================== kasan: CONFIG_KASAN_INLINE enabled BUG: KASAN: use-after-scope in __debug_check_no_obj_freed lib/debugobjects.c:778 [inline] BUG: KASAN: use-after-scope in debug_check_no_obj_freed+0x45f/0x58d lib/debugobjects.c:818 kasan: GPF could be caused by NULL-ptr deref or user memory access Read of size 8 at addr ffff8881da94a6c8 by task khugepaged/1013 general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 7749 Comm: syz-executor1 Not tainted 4.20.0-rc2+ #295 CPU: 1 PID: 1013 Comm: khugepaged Not tainted 4.20.0-rc2+ #295 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:vmalloc_fault+0x426/0x770 arch/x86/mm/fault.c:405 Call Trace: ------------[ cut here ]------------ __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 Bad or missing usercopy whitelist? Kernel memory overwrite attempt detected to SLAB object '' (offset 18446744069414924669, size 2)! WARNING: CPU: 0 PID: 7749 at mm/usercopy.c:83 usercopy_warn+0xee/0x110 mm/usercopy.c:78 Kernel panic - not syncing: panic_on_warn set ... print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __debug_check_no_obj_freed lib/debugobjects.c:778 [inline] debug_check_no_obj_freed+0x45f/0x58d lib/debugobjects.c:818 free_pages_prepare mm/page_alloc.c:1034 [inline] free_pcp_prepare mm/page_alloc.c:1048 [inline] free_unref_page_prepare mm/page_alloc.c:2743 [inline] free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2812 release_pages+0xab5/0x26a0 mm/swap.c:791 pagevec_lru_move_fn+0x28c/0x350 mm/swap.c:213 __pagevec_lru_add mm/swap.c:918 [inline] __lru_cache_add+0x2d3/0x4e0 mm/swap.c:409 lru_cache_add+0x417/0xa50 mm/swap.c:445 putback_lru_page+0x8c/0x280 mm/vmscan.c:1007 release_pte_page+0x216/0x3a0 mm/khugepaged.c:508 __collapse_huge_page_copy mm/khugepaged.c:664 [inline] collapse_huge_page mm/khugepaged.c:1060 [inline] khugepaged_scan_pmd+0x2573/0x3d60 mm/khugepaged.c:1216 khugepaged_scan_mm_slot mm/khugepaged.c:1703 [inline] khugepaged_do_scan mm/khugepaged.c:1784 [inline] khugepaged+0xf20/0x1750 mm/khugepaged.c:1829 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8881da94a000 which belongs to the cache ,ԁ of size -30591 The buggy address is located 32327 bytes to the right of -30591-byte region [ffff8881da94a000, ffff8881da942881) The buggy address belongs to the page: page:ffffea00076a5280 count:1 mapcount:0 mapping:ffff8881da813e40 index:0xffff8881da94afb9 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea0006e70848 ffffea00076a5188 ffff8881da813e40 raw: ffff8881da94afb9 ffff8881da94a000 0000000100000047 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881da94a580: 00 00 00 00 fc fc 00 00 00 00 00 fc fc 00 00 00 ffff8881da94a600: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 >ffff8881da94a680: f1 00 f2 f2 f2 f2 f2 f2 f2 f8 f2 f2 f2 00 00 fc ^ ffff8881da94a700: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 ffff8881da94a780: f1 f8 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 ================================================================== kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access Shutting down cpus with NMI Kernel Offset: disabled ====================================================== WARNING: possible circular locking dependency detected 4.20.0-rc2+ #295 Not tainted ------------------------------------------------------ khugepaged/1013 is trying to acquire lock: 0000000079711abb ((console_sem).lock){-.-.}, at: down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 but task is already holding lock: 00000000222e7003 (report_lock){....}, at: kasan_start_report mm/kasan/report.c:170 [inline] 00000000222e7003 (report_lock){....}, at: kasan_report_error mm/kasan/report.c:346 [inline] 00000000222e7003 (report_lock){....}, at: kasan_report+0x8b/0x110 mm/kasan/report.c:412 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (report_lock){....}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 kasan_start_report mm/kasan/report.c:170 [inline] kasan_report_error mm/kasan/report.c:346 [inline] kasan_report+0x8b/0x110 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __debug_check_no_obj_freed lib/debugobjects.c:778 [inline] debug_check_no_obj_freed+0x45f/0x58d lib/debugobjects.c:818 free_pages_prepare mm/page_alloc.c:1034 [inline] free_pcp_prepare mm/page_alloc.c:1048 [inline] free_unref_page_prepare mm/page_alloc.c:2743 [inline] free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2812 release_pages+0xab5/0x26a0 mm/swap.c:791 pagevec_lru_move_fn+0x28c/0x350 mm/swap.c:213 __pagevec_lru_add mm/swap.c:918 [inline] __lru_cache_add+0x2d3/0x4e0 mm/swap.c:409 lru_cache_add+0x417/0xa50 mm/swap.c:445 putback_lru_page+0x8c/0x280 mm/vmscan.c:1007 release_pte_page+0x216/0x3a0 mm/khugepaged.c:508 __collapse_huge_page_copy mm/khugepaged.c:664 [inline] collapse_huge_page mm/khugepaged.c:1060 [inline] khugepaged_scan_pmd+0x2573/0x3d60 mm/khugepaged.c:1216 khugepaged_scan_mm_slot mm/khugepaged.c:1703 [inline] khugepaged_do_scan mm/khugepaged.c:1784 [inline] khugepaged+0xf20/0x1750 mm/khugepaged.c:1829 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 -> #3 (&obj_hash[i].lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 __debug_object_init+0x127/0x1290 lib/debugobjects.c:384 debug_object_init+0x16/0x20 lib/debugobjects.c:432 debug_hrtimer_init kernel/time/hrtimer.c:410 [inline] debug_init kernel/time/hrtimer.c:458 [inline] hrtimer_init+0x97/0x490 kernel/time/hrtimer.c:1308 init_dl_task_timer+0x1b/0x50 kernel/sched/deadline.c:1057 __sched_fork+0x2ae/0x590 kernel/sched/core.c:2166 init_idle+0x75/0x740 kernel/sched/core.c:5374 sched_init+0xb33/0xc07 kernel/sched/core.c:6060 start_kernel+0x4be/0xa2b init/main.c:608 x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:472 x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:451 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #2 (&rq->lock){-.-.}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2d/0x40 kernel/locking/spinlock.c:144 rq_lock kernel/sched/sched.h:1126 [inline] task_fork_fair+0xb0/0x6d0 kernel/sched/fair.c:9768 sched_fork+0x443/0xba0 kernel/sched/core.c:2359 copy_process+0x25b8/0x87a0 kernel/fork.c:1887 _do_fork+0x1cb/0x11d0 kernel/fork.c:2216 kernel_thread+0x34/0x40 kernel/fork.c:2275 rest_init+0x28/0x372 init/main.c:409 arch_call_rest_init+0xe/0x1b start_kernel+0x9f0/0xa2b init/main.c:745 x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:472 x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:451 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #1 (&p->pi_lock){-.-.}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 try_to_wake_up+0xdc/0x1490 kernel/sched/core.c:1965 wake_up_process+0x10/0x20 kernel/sched/core.c:2129 __up.isra.1+0x1c0/0x2a0 kernel/locking/semaphore.c:262 up+0x13c/0x1c0 kernel/locking/semaphore.c:187 __up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:236 console_unlock+0x811/0x1190 kernel/printk/printk.c:2432 vprintk_emit+0x391/0x990 kernel/printk/printk.c:1922 vprintk_default+0x28/0x30 kernel/printk/printk.c:1964 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1997 kobject_uevent_env+0x96/0x101e lib/kobject_uevent.c:467 call_crda net/wireless/reg.c:556 [inline] reg_query_database+0x283/0x400 net/wireless/reg.c:1104 reg_process_hint_core net/wireless/reg.c:2339 [inline] reg_process_hint+0x189/0xec0 net/wireless/reg.c:2677 reg_process_pending_hints net/wireless/reg.c:2767 [inline] reg_todo+0x49a/0xc20 net/wireless/reg.c:2844 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 -> #0 ((console_sem).lock){-.-.}: lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xae/0x1f0 kernel/printk/printk.c:219 console_trylock+0x15/0xa0 kernel/printk/printk.c:2247 console_trylock_spinning kernel/printk/printk.c:1653 [inline] vprintk_emit+0x372/0x990 kernel/printk/printk.c:1921 vprintk_default+0x28/0x30 kernel/printk/printk.c:1964 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1997 kasan_start_report mm/kasan/report.c:171 [inline] kasan_report_error mm/kasan/report.c:346 [inline] kasan_report+0x9b/0x110 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __debug_check_no_obj_freed lib/debugobjects.c:778 [inline] debug_check_no_obj_freed+0x45f/0x58d lib/debugobjects.c:818 free_pages_prepare mm/page_alloc.c:1034 [inline] free_pcp_prepare mm/page_alloc.c:1048 [inline] free_unref_page_prepare mm/page_alloc.c:2743 [inline] free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2812 release_pages+0xab5/0x26a0 mm/swap.c:791 pagevec_lru_move_fn+0x28c/0x350 mm/swap.c:213 __pagevec_lru_add mm/swap.c:918 [inline] __lru_cache_add+0x2d3/0x4e0 mm/swap.c:409 lru_cache_add+0x417/0xa50 mm/swap.c:445 putback_lru_page+0x8c/0x280 mm/vmscan.c:1007 release_pte_page+0x216/0x3a0 mm/khugepaged.c:508 __collapse_huge_page_copy mm/khugepaged.c:664 [inline] collapse_huge_page mm/khugepaged.c:1060 [inline] khugepaged_scan_pmd+0x2573/0x3d60 mm/khugepaged.c:1216 khugepaged_scan_mm_slot mm/khugepaged.c:1703 [inline] khugepaged_do_scan mm/khugepaged.c:1784 [inline] khugepaged+0xf20/0x1750 mm/khugepaged.c:1829 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 other info that might help us debug this: Chain exists of: (console_sem).lock --> &obj_hash[i].lock --> report_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(report_lock); lock(&obj_hash[i].lock); lock(report_lock); lock((console_sem).lock); *** DEADLOCK *** 3 locks held by khugepaged/1013: #0: 000000004873e9d5 (&mm->mmap_sem){++++}, at: collapse_huge_page mm/khugepaged.c:1007 [inline] #0: 000000004873e9d5 (&mm->mmap_sem){++++}, at: khugepaged_scan_pmd+0x1842/0x3d60 mm/khugepaged.c:1216 #1: 000000000190329a (&obj_hash[i].lock){-.-.}, at: __debug_check_no_obj_freed lib/debugobjects.c:777 [inline] #1: 000000000190329a (&obj_hash[i].lock){-.-.}, at: debug_check_no_obj_freed+0x17a/0x58d lib/debugobjects.c:818 #2: 00000000222e7003 (report_lock){....}, at: kasan_start_report mm/kasan/report.c:170 [inline] #2: 00000000222e7003 (report_lock){....}, at: kasan_report_error mm/kasan/report.c:346 [inline] #2: 00000000222e7003 (report_lock){....}, at: kasan_report+0x8b/0x110 mm/kasan/report.c:412 stack backtrace: CPU: 1 PID: 1013 Comm: khugepaged Not tainted 4.20.0-rc2+ #295 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_circular_bug.isra.35.cold.54+0x1bd/0x27d kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1863 [inline] check_prevs_add kernel/locking/lockdep.c:1976 [inline] validate_chain kernel/locking/lockdep.c:2347 [inline] __lock_acquire+0x3399/0x4c20 kernel/locking/lockdep.c:3341 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x99/0xd0 kernel/locking/spinlock.c:152 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136 __down_trylock_console_sem+0xae/0x1f0 kernel/printk/printk.c:219 console_trylock+0x15/0xa0 kernel/printk/printk.c:2247 console_trylock_spinning kernel/printk/printk.c:1653 [inline] vprintk_emit+0x372/0x990 kernel/printk/printk.c:1921 vprintk_default+0x28/0x30 kernel/printk/printk.c:1964 vprintk_func+0x7e/0x181 kernel/printk/printk_safe.c:398 printk+0xa7/0xcf kernel/printk/printk.c:1997 kasan_start_report mm/kasan/report.c:171 [inline] kasan_report_error mm/kasan/report.c:346 [inline] kasan_report+0x9b/0x110 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __debug_check_no_obj_freed lib/debugobjects.c:778 [inline] debug_check_no_obj_freed+0x45f/0x58d lib/debugobjects.c:818 free_pages_prepare mm/page_alloc.c:1034 [inline] free_pcp_prepare mm/page_alloc.c:1048 [inline] free_unref_page_prepare mm/page_alloc.c:2743 [inline] free_unref_page_list+0x3c4/0x11e0 mm/page_alloc.c:2812 release_pages+0xab5/0x26a0 mm/swap.c:791 pagevec_lru_move_fn+0x28c/0x350 mm/swap.c:213 __pagevec_lru_add mm/swap.c:918 [inline] __lru_cache_add+0x2d3/0x4e0 mm/swap.c:409 lru_cache_add+0x417/0xa50 mm/swap.c:445 Lost 76 message(s)! 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