================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005 Read of size 8 at addr ffff88804deae410 by task syz-executor.5/17830 CPU: 0 PID: 17830 Comm: syz-executor.5 Not tainted 6.9.0-rc7-syzkaller-00012-gdccb07f2914c #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+0x190/0x650 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 handle_softirqs+0x2d8/0x990 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 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:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:206 Code: 8b 3d 4c f9 3e 0c 48 89 de 5b e9 23 2c 59 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 c0 d3 03 00 65 8b 15 30 cb 6d 7e f7 c2 00 01 ff 00 RSP: 0018:ffffc900046972c8 EFLAGS: 00000246 RAX: ffffffff8206b114 RBX: ffffea000155ee40 RCX: ffff88805da19e00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea000155ee40 RBP: 0000000000000000 R08: ffffffff8206b80c R09: 1ffffd40002abdc8 R10: dffffc0000000000 R11: fffff940002abdc9 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffea000155ee40 R15: ffffea000155ee48 page_ext_get+0x14/0x2a0 mm/page_ext.c:505 __page_table_check_zero+0x13d/0x4a0 mm/page_table_check.c:140 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+0x324/0x640 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+0xa86/0xcb0 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: 0033:0x7f1df727caaf 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:00007f1df7f64e80 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000013bd7ef RCX: 00007f1df727caaf RDX: 00000000013bd7ef RSI: 00007f1ded000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005599 R10: 00000000000003ca R11: 0000000000000293 R12: 0000000000000003 R13: 00007f1df7f64f80 R14: 00007f1df7f64f40 R15: 00007f1ded000000 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:3804 [inline] slab_alloc_node mm/slub.c:3851 [inline] kmem_cache_alloc_node+0x194/0x390 mm/slub.c:3894 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+0x226/0x8f0 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+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 5076: 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:2111 [inline] slab_free mm/slub.c:4286 [inline] kmem_cache_free+0x10b/0x2d0 mm/slub.c:4350 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+0xaff/0x1830 kernel/rcu/tree.c:2471 handle_softirqs+0x2d8/0x990 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 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 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+0x17f0/0x4a50 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+0x138/0x2d0 fs/super.c:641 kill_block_super+0x44/0x90 fs/super.c:1675 deactivate_locked_super+0xc6/0x130 fs/super.c:472 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x251/0x310 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 ffff88804deada00 which belongs to the cache task_struct of size 7424 The buggy address is located 2576 bytes inside of freed 7424-byte region [ffff88804deada00, ffff88804deaf700) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4dea8 head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802d59ac81 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888015ee5500 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88802d59ac81 head: 00fff00000000840 ffff888015ee5500 dead000000000122 0000000000000000 head: 0000000000000000 0000000000040004 00000001ffffffff ffff88802d59ac81 head: 00fff00000000003 ffffea000137aa01 dead000000000122 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 15533, tgid -1023954332 (kworker/u8:13), ts 15533, free_ts 853023336909 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:2180 allocate_slab mm/slub.c:2343 [inline] new_slab+0x84/0x2f0 mm/slub.c:2396 ___slab_alloc+0xc73/0x1260 mm/slub.c:3530 __slab_alloc mm/slub.c:3615 [inline] __slab_alloc_node mm/slub.c:3668 [inline] slab_alloc_node mm/slub.c:3841 [inline] kmem_cache_alloc_node+0x24a/0x390 mm/slub.c:3894 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+0x226/0x8f0 kernel/fork.c:2797 user_mode_thread+0x132/0x1a0 kernel/fork.c:2875 call_usermodehelper_exec_sync kernel/umh.c:133 [inline] call_usermodehelper_exec_work+0x9b/0x230 kernel/umh.c:164 process_one_work kernel/workqueue.c:3267 [inline] process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3348 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429 kthread+0x2f2/0x390 kernel/kthread.c:388 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 page last free pid 17281 tgid 17281 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 discard_slab mm/slub.c:2442 [inline] __put_partials+0xeb/0x130 mm/slub.c:2911 put_cpu_partial+0x17c/0x250 mm/slub.c:2986 __slab_free+0x2ea/0x3d0 mm/slub.c:4157 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x5e/0xc0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3851 [inline] kmem_cache_alloc+0x174/0x350 mm/slub.c:3858 getname_flags+0xbd/0x4f0 fs/namei.c:139 vfs_fstatat+0x11c/0x190 fs/stat.c:303 __do_sys_newfstatat fs/stat.c:468 [inline] __se_sys_newfstatat fs/stat.c:462 [inline] __x64_sys_newfstatat+0x117/0x190 fs/stat.c:462 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 Memory state around the buggy address: ffff88804deae300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804deae380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804deae400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804deae480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804deae500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 8b 3d 4c f9 3e 0c mov 0xc3ef94c(%rip),%edi # 0xc3ef952 6: 48 89 de mov %rbx,%rsi 9: 5b pop %rbx a: e9 23 2c 59 00 jmp 0x592c32 f: 0f 1f 00 nopl (%rax) 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: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: f3 0f 1e fa endbr64 26: 48 8b 04 24 mov (%rsp),%rax * 2a: 65 48 8b 0c 25 c0 d3 mov %gs:0x3d3c0,%rcx <-- trapping instruction 31: 03 00 33: 65 8b 15 30 cb 6d 7e mov %gs:0x7e6dcb30(%rip),%edx # 0x7e6dcb6a 3a: f7 c2 00 01 ff 00 test $0xff0100,%edx