================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x41b9/0x5f30 kernel/locking/lockdep.c:4956 Read of size 8 at addr ffff888027246340 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-rc2-next-20230515-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351 print_report mm/kasan/report.c:462 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:571 __lock_acquire+0x41b9/0x5f30 kernel/locking/lockdep.c:4956 lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5705 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 try_to_wake_up+0xab/0x1a50 kernel/sched/core.c:4191 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers+0x234/0x330 kernel/time/timer.c:1751 __run_timers kernel/time/timer.c:2022 [inline] __run_timers kernel/time/timer.c:1995 [inline] run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035 __do_softirq+0x1d4/0x905 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x40/0x50 drivers/acpi/processor_idle.c:113 Code: eb 03 83 e3 01 89 de 0f 1f 44 00 00 84 db 75 1b 0f 1f 44 00 00 66 90 0f 1f 44 00 00 0f 00 2d 57 4e a1 00 0f 1f 44 00 00 fb f4 5b c3 cc 0f 1f 00 66 0f 1f 84 00 00 00 00 00 55 48 89 fd 53 0f RSP: 0018:ffffffff8c407d18 EFLAGS: 00000246 RAX: ffffffff8c495780 RBX: 0000000000000000 RCX: ffffffff8a10cd15 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880146fa864 R08: 0000000000000001 R09: ffffed1017306d9d R10: ffff8880b9836ceb R11: 0000000000000000 R12: 0000000000000001 R13: ffff8880146fa800 R14: ffff8880146fa864 R15: 0000000000000000 acpi_idle_do_entry+0x53/0x70 drivers/acpi/processor_idle.c:573 acpi_idle_enter+0x173/0x290 drivers/acpi/processor_idle.c:711 cpuidle_enter_state+0xd3/0x6f0 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x2fe/0x3c0 kernel/sched/idle.c:282 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 rest_init+0x16f/0x2b0 init/main.c:735 arch_call_rest_init+0x13/0x30 init/main.c:834 start_kernel+0x3b6/0x490 init/main.c:1088 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb3/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0xf4/0xfb Allocated by task 2: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:711 [inline] slab_alloc_node mm/slub.c:3451 [inline] kmem_cache_alloc_node+0x185/0x3e0 mm/slub.c:3496 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1104 [inline] copy_process+0x3c0/0x7600 kernel/fork.c:2329 kernel_clone+0xeb/0x890 kernel/fork.c:2914 kernel_thread+0xc0/0x100 kernel/fork.c:2976 create_kthread kernel/kthread.c:402 [inline] kthreadd+0x50c/0x790 kernel/kthread.c:737 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Freed by task 0: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3786 [inline] kmem_cache_free+0xe9/0x480 mm/slub.c:3808 put_task_struct include/linux/sched/task.h:126 [inline] delayed_put_task_struct+0x1f5/0x280 kernel/exit.c:226 rcu_do_batch kernel/rcu/tree.c:2135 [inline] rcu_core+0x802/0x1bc0 kernel/rcu/tree.c:2399 __do_softirq+0x1d4/0x905 kernel/softirq.c:553 Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:491 __call_rcu_common.constprop.0+0x99/0x790 kernel/rcu/tree.c:2649 put_task_struct_rcu_user+0x87/0xc0 kernel/exit.c:232 context_switch kernel/sched/core.c:5346 [inline] __schedule+0x1d1d/0x5790 kernel/sched/core.c:6669 schedule_idle+0x5b/0x80 kernel/sched/core.c:6773 do_idle+0x273/0x3c0 kernel/sched/idle.c:310 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 start_secondary+0x221/0x2b0 arch/x86/kernel/smpboot.c:269 secondary_startup_64_no_verify+0xf4/0xfb Second to last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:491 __call_rcu_common.constprop.0+0x99/0x790 kernel/rcu/tree.c:2649 put_task_struct_rcu_user+0x87/0xc0 kernel/exit.c:232 context_switch kernel/sched/core.c:5346 [inline] __schedule+0x1d1d/0x5790 kernel/sched/core.c:6669 schedule_idle+0x5b/0x80 kernel/sched/core.c:6773 do_idle+0x273/0x3c0 kernel/sched/idle.c:310 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379 rest_init+0x16f/0x2b0 init/main.c:735 arch_call_rest_init+0x13/0x30 init/main.c:834 start_kernel+0x3b6/0x490 init/main.c:1088 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb3/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0xf4/0xfb The buggy address belongs to the object at ffff888027245940 which belongs to the cache task_struct of size 7360 The buggy address is located 2560 bytes inside of freed 7360-byte region [ffff888027245940, ffff888027247600) The buggy address belongs to the physical page: page:ffffea00009c9000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27240 head:ffffea00009c9000 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff888140007500 ffffea0000802800 dead000000000002 raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2, tgid 2 (kthreadd), ts 11223047801, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731 prep_new_page mm/page_alloc.c:1738 [inline] get_page_from_freelist+0xf67/0x2a80 mm/page_alloc.c:3539 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4805 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x28e/0x380 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3192 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3291 __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] kmem_cache_alloc_node+0x138/0x3e0 mm/slub.c:3496 alloc_task_struct_node kernel/fork.c:173 [inline] dup_task_struct kernel/fork.c:1104 [inline] copy_process+0x3c0/0x7600 kernel/fork.c:2329 kernel_clone+0xeb/0x890 kernel/fork.c:2914 kernel_thread+0xc0/0x100 kernel/fork.c:2976 create_kthread kernel/kthread.c:402 [inline] kthreadd+0x50c/0x790 kernel/kthread.c:737 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 page_owner free stack trace missing Memory state around the buggy address: ffff888027246200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027246280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888027246300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888027246380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027246400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: eb 03 jmp 0x5 2: 83 e3 01 and $0x1,%ebx 5: 89 de mov %ebx,%esi 7: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) c: 84 db test %bl,%bl e: 75 1b jne 0x2b 10: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 15: 66 90 xchg %ax,%ax 17: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1c: 0f 00 2d 57 4e a1 00 verw 0xa14e57(%rip) # 0xa14e7a 23: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 28: fb sti 29: f4 hlt * 2a: fa cli <-- trapping instruction 2b: 5b pop %rbx 2c: c3 retq 2d: cc int3 2e: 0f 1f 00 nopl (%rax) 31: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 38: 00 00 3a: 55 push %rbp 3b: 48 89 fd mov %rdi,%rbp 3e: 53 push %rbx 3f: 0f .byte 0xf