================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2dd6/0x3b30 kernel/locking/lockdep.c:5005 Read of size 8 at addr ffff88801faf0a10 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.9.0-rc2-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 __lock_acquire+0x2dd6/0x3b30 kernel/locking/lockdep.c:5005 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline] try_to_wake_up+0x9a/0x13e0 kernel/sched/core.c:4262 call_timer_fn+0x1a0/0x610 kernel/time/timer.c:1793 expire_timers kernel/time/timer.c:1844 [inline] __run_timers+0x74b/0xaf0 kernel/time/timer.c:2418 __run_timer_base kernel/time/timer.c:2429 [inline] __run_timer_base kernel/time/timer.c:2422 [inline] run_timer_base+0x111/0x190 kernel/time/timer.c:2438 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2448 __do_softirq+0x218/0x922 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:633 [inline] irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 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:default_idle+0xf/0x20 arch/x86/kernel/process.c:743 Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 b2 31 00 fb f4 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 RSP: 0018:ffffc90000467e08 EFLAGS: 00000246 RAX: 0000000000074871 RBX: 0000000000000001 RCX: ffffffff8ad4ea39 RDX: 0000000000000000 RSI: ffffffff8b0cd500 RDI: ffffffff8b6f0860 RBP: ffffed1002b61488 R08: 0000000000000001 R09: ffffed1005866fdd R10: ffff88802c337eeb R11: 0000000000000000 R12: 0000000000000001 R13: ffff888015b0a440 R14: ffffffff8f9f6bd0 R15: 0000000000000000 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x32c/0x3f0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x220/0x2b0 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x148 Allocated by task 8693: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x177/0x340 mm/slub.c:3888 alloc_task_struct_node kernel/fork.c:176 [inline] dup_task_struct kernel/fork.c:1106 [inline] copy_process+0x4a3/0x6f00 kernel/fork.c:2219 kernel_clone+0xfd/0x980 kernel/fork.c:2796 __do_sys_clone3+0x1f5/0x270 kernel/fork.c:3097 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] int80_emulation+0x10b/0x200 arch/x86/entry/common.c:253 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:626 Freed by task 15: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:240 [inline] __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0x12e/0x380 mm/slub.c:4344 put_task_struct include/linux/sched/task.h:138 [inline] put_task_struct include/linux/sched/task.h:125 [inline] delayed_put_task_struct+0x22c/0x300 kernel/exit.c:229 rcu_do_batch kernel/rcu/tree.c:2196 [inline] rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2471 __do_softirq+0x218/0x922 kernel/softirq.c:554 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:2734 put_task_struct_rcu_user kernel/exit.c:235 [inline] put_task_struct_rcu_user+0x87/0xd0 kernel/exit.c:232 context_switch kernel/sched/core.c:5412 [inline] __schedule+0xf1d/0x5d00 kernel/sched/core.c:6746 schedule_idle+0x59/0x90 kernel/sched/core.c:6864 do_idle+0x287/0x3f0 kernel/sched/idle.c:360 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 rest_init+0x16b/0x2b0 init/main.c:732 start_kernel+0x3a3/0x490 init/main.c:1074 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148 The buggy address belongs to the object at ffff88801faf0000 which belongs to the cache task_struct of size 9024 The buggy address is located 2576 bytes inside of freed 9024-byte region [ffff88801faf0000, ffff88801faf2340) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1faf0 head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88801e364a41 flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000840 ffff888015e96140 ffffea0000633e00 dead000000000002 raw: 0000000000000000 0000000000030003 00000001ffffffff ffff88801e364a41 head: 00fff80000000840 ffff888015e96140 ffffea0000633e00 dead000000000002 head: 0000000000000000 0000000000030003 00000001ffffffff ffff88801e364a41 head: 00fff80000000003 ffffea00007ebc01 ffffea00007ebc48 00000000ffffffff head: 0000000800000000 0000000000000000 00000000ffffffff 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 1085, tgid 1085 (kworker/u32:6), ts 8838464159, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page mm/slub.c:2175 [inline] allocate_slab mm/slub.c:2338 [inline] new_slab+0xcc/0x3a0 mm/slub.c:2391 ___slab_alloc+0x670/0x16d0 mm/slub.c:3525 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610 __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmem_cache_alloc_node+0x10a/0x340 mm/slub.c:3888 alloc_task_struct_node kernel/fork.c:176 [inline] dup_task_struct kernel/fork.c:1106 [inline] copy_process+0x4a3/0x6f00 kernel/fork.c:2219 kernel_clone+0xfd/0x980 kernel/fork.c:2796 user_mode_thread+0xb4/0xf0 kernel/fork.c:2874 call_usermodehelper_exec_work kernel/umh.c:172 [inline] call_usermodehelper_exec_work+0xcb/0x170 kernel/umh.c:158 process_one_work+0x902/0x1a30 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 page_owner free stack trace missing Memory state around the buggy address: ffff88801faf0900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801faf0980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801faf0a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801faf0a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801faf0b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 4c 01 c7 add %r8,%rdi 3: 4c 29 c2 sub %r8,%rdx 6: e9 72 ff ff ff jmp 0xffffff7d b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d 73 b2 31 00 verw 0x31b273(%rip) # 0x31b29b 28: fb sti 29: f4 hlt * 2a: fa cli <-- trapping instruction 2b: c3 ret 2c: cc int3 2d: cc int3 2e: cc int3 2f: cc int3 30: 66 66 2e 0f 1f 84 00 data16 cs nopw 0x0(%rax,%rax,1) 37: 00 00 00 00 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop