================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005 Read of size 8 at addr ffff8880264fa810 by task syz-executor.4/8545 CPU: 0 PID: 8545 Comm: syz-executor.4 Not tainted 6.9.0-rc5-syzkaller-00031-g71b1543c83d6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4262 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793 expire_timers kernel/time/timer.c:1844 [inline] __run_timers kernel/time/timer.c:2418 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2429 run_timer_base kernel/time/timer.c:2438 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2448 __do_softirq+0x2c6/0x980 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:220 [inline] RIP: 0010:unwind_next_frame+0x2ca/0x2a00 arch/x86/kernel/unwind_orc.c:494 Code: 7f 48 8d 8c 00 b8 7e 24 90 48 c7 c0 ba 4f cc 90 48 89 4c 24 18 48 39 c1 0f 83 bd 1d 00 00 4b 8d 0c 64 48 8d 8c 09 b8 7e 24 90 <48> 39 c1 0f 87 a8 1d 00 00 44 89 e7 44 89 fe e8 e2 bf 54 00 45 39 RSP: 0018:ffffc900057eee00 EFLAGS: 00000297 RAX: ffffffff90cc4fba RBX: ffffffff90cd2f08 RCX: ffffffff9028898e RDX: ffff88801832da00 RSI: 00000000000037d2 RDI: 00000000000ac000 RBP: 00000000000037d2 R08: ffffffff814141b4 R09: ffffffff814158df R10: 0000000000000003 R11: ffff88801832da00 R12: 000000000000ac79 R13: 00000000000ac001 R14: dffffc0000000000 R15: 000000000000ac72 __unwind_start+0x641/0x7c0 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x103/0x1b0 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __set_page_owner+0x8d/0x810 mm/page_owner.c:325 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 alloc_pages_mpol+0x3e8/0x680 mm/mempolicy.c:2264 shmem_alloc_folio mm/shmem.c:1628 [inline] shmem_alloc_and_add_folio+0x24d/0xbc0 mm/shmem.c:1668 shmem_get_folio_gfp+0x82d/0x1f50 mm/shmem.c:2055 shmem_get_folio mm/shmem.c:2160 [inline] shmem_write_begin+0x170/0x4d0 mm/shmem.c:2744 generic_perform_write+0x322/0x640 mm/filemap.c:3974 shmem_file_write_iter+0xfc/0x120 mm/shmem.c:2920 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa84/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f095c87cbef Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 b9 80 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 0c 81 02 00 48 RSP: 002b:00007f095d60be80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f095c87cbef RDX: 0000000001000000 RSI: 00007f0952600000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000061a6 R10: 0000000020006742 R11: 0000000000000293 R12: 0000000000000003 R13: 00007f095d60bf80 R14: 00007f095d60bf40 R15: 00007f0952600000 Allocated by task 2: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 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+0x194/0x380 mm/slub.c:3888 alloc_task_struct_node kernel/fork.c:176 [inline] dup_task_struct+0x57/0x7d0 kernel/fork.c:1107 copy_process+0x5d1/0x3df0 kernel/fork.c:2220 kernel_clone+0x223/0x870 kernel/fork.c:2797 kernel_thread+0x1bc/0x240 kernel/fork.c:2859 create_kthread kernel/kthread.c:411 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:764 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 15: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 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+0x10b/0x2c0 mm/slub.c:4344 put_task_struct include/linux/sched/task.h:138 [inline] delayed_put_task_struct+0x125/0x2f0 kernel/exit.c:229 rcu_do_batch kernel/rcu/tree.c:2196 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2471 __do_softirq+0x2c6/0x980 kernel/softirq.c:554 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:2734 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:2838 context_switch kernel/sched/core.c:5412 [inline] __schedule+0x179e/0x4a00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6838 nilfs_segctor_kill_thread fs/nilfs2/segment.c:2645 [inline] nilfs_segctor_destroy fs/nilfs2/segment.c:2727 [inline] nilfs_detach_log_writer+0x2e8/0xbe0 fs/nilfs2/segment.c:2816 nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:499 generic_shutdown_super+0x136/0x2d0 fs/super.c:641 kill_block_super+0x44/0x90 fs/super.c:1675 deactivate_locked_super+0xc4/0x130 fs/super.c:472 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24f/0x310 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+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880264f9e00 which belongs to the cache task_struct of size 7424 The buggy address is located 2576 bytes inside of freed 7424-byte region [ffff8880264f9e00, ffff8880264fbb00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x264f8 head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888024e29181 flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000840 ffff8880162a6500 ffffea0000b15c00 dead000000000002 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff888024e29181 head: 00fff80000000840 ffff8880162a6500 ffffea0000b15c00 dead000000000002 head: 0000000000000000 0000000000040004 00000001ffffffff ffff888024e29181 head: 00fff80000000003 ffffea0000993e01 ffffea0000993e48 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 34, tgid 1431231104 (kworker/u8:2), ts 34, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 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+0x5f/0x160 mm/slub.c:2175 allocate_slab mm/slub.c:2338 [inline] new_slab+0x84/0x2f0 mm/slub.c:2391 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmem_cache_alloc_node+0x24a/0x380 mm/slub.c:3888 alloc_task_struct_node kernel/fork.c:176 [inline] dup_task_struct+0x57/0x7d0 kernel/fork.c:1107 copy_process+0x5d1/0x3df0 kernel/fork.c:2220 kernel_clone+0x223/0x870 kernel/fork.c:2797 user_mode_thread+0x132/0x1a0 kernel/fork.c:2875 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:172 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 page_owner free stack trace missing Memory state around the buggy address: ffff8880264fa700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880264fa780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880264fa800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880264fa880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880264fa900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 7f 48 jg 0x4a 2: 8d 8c 00 b8 7e 24 90 lea -0x6fdb8148(%rax,%rax,1),%ecx 9: 48 c7 c0 ba 4f cc 90 mov $0xffffffff90cc4fba,%rax 10: 48 89 4c 24 18 mov %rcx,0x18(%rsp) 15: 48 39 c1 cmp %rax,%rcx 18: 0f 83 bd 1d 00 00 jae 0x1ddb 1e: 4b 8d 0c 64 lea (%r12,%r12,2),%rcx 22: 48 8d 8c 09 b8 7e 24 lea -0x6fdb8148(%rcx,%rcx,1),%rcx 29: 90 * 2a: 48 39 c1 cmp %rax,%rcx <-- trapping instruction 2d: 0f 87 a8 1d 00 00 ja 0x1ddb 33: 44 89 e7 mov %r12d,%edi 36: 44 89 fe mov %r15d,%esi 39: e8 e2 bf 54 00 call 0x54c020 3e: 45 rex.RB 3f: 39 .byte 0x39