================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2dd6/0x3b30 kernel/locking/lockdep.c:5005 Read of size 8 at addr ffff888027cfae50 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.9.0-rc4-syzkaller-00113-g2668e3ae2ef3 #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 03 88 2b 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:ffffffff8d407e20 EFLAGS: 00000246 RAX: 000000000014f693 RBX: 0000000000000000 RCX: ffffffff8adafa09 RDX: 0000000000000000 RSI: ffffffff8b0cae00 RDI: ffffffff8b6f56a0 RBP: fffffbfff1a92ae8 R08: 0000000000000001 R09: ffffed100d646fdd R10: ffff88806b237eeb R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8d495740 R14: ffffffff8f9f1f50 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 rest_init+0x16b/0x2b0 init/main.c:737 start_kernel+0x3a3/0x490 init/main.c:1079 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 Allocated by task 10365: 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+0x4b7/0x9160 kernel/fork.c:2219 kernel_clone+0xfd/0x980 kernel/fork.c:2796 __do_sys_clone3+0x1f5/0x270 kernel/fork.c:3097 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 0: 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_loop kernel/sched/core.c:6823 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6838 synchronize_rcu_expedited+0x610/0x7a0 kernel/rcu/tree_exp.h:954 bdi_remove_from_list mm/backing-dev.c:1035 [inline] bdi_unregister+0x17b/0x640 mm/backing-dev.c:1043 generic_shutdown_super+0x29c/0x3d0 fs/super.c:681 kill_anon_super+0x3a/0x60 fs/super.c:1225 afs_kill_super+0xe6/0x180 fs/afs/super.c:550 deactivate_locked_super+0xbe/0x1a0 fs/super.c:472 deactivate_super+0xde/0x100 fs/super.c:505 cleanup_mnt+0x222/0x450 fs/namespace.c:1267 task_work_run+0x14e/0x250 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xdc/0x260 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888027cfa440 which belongs to the cache task_struct of size 9024 The buggy address is located 2576 bytes inside of freed 9024-byte region [ffff888027cfa440, ffff888027cfc780) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27cf8 head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88804c357e41 ksm flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000840 ffff8880162f0140 ffffea0000938000 dead000000000003 raw: 0000000000000000 0000000000030003 00000001ffffffff ffff88804c357e41 head: 00fff80000000840 ffff8880162f0140 ffffea0000938000 dead000000000003 head: 0000000000000000 0000000000030003 00000001ffffffff ffff88804c357e41 head: 00fff80000000003 ffffea00009f3e01 ffffea00009f3e48 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 2, tgid 2 (kthreadd), ts 14330768767, 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+0x66d/0x1790 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+0x4b7/0x9160 kernel/fork.c:2219 kernel_clone+0xfd/0x980 kernel/fork.c:2796 kernel_thread+0xc0/0x100 kernel/fork.c:2858 create_kthread kernel/kthread.c:411 [inline] kthreadd+0x4ef/0x7d0 kernel/kthread.c:764 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 page_owner free stack trace missing Memory state around the buggy address: ffff888027cfad00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027cfad80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888027cfae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888027cfae80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027cfaf00: 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 03 88 2b 00 verw 0x2b8803(%rip) # 0x2b882b 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