================================================================== BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 Read of size 1 at addr ffff8880445ee418 by task kworker/u32:14/16975 CPU: 0 UID: 0 PID: 16975 Comm: kworker/u32:14 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: events_unbound toggle_allocation_gate Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 __kasan_check_byte+0x36/0x50 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire kernel/locking/lockdep.c:5842 [inline] lock_acquire+0xfc/0x330 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 p9_tag_remove net/9p/client.c:274 [inline] p9_req_put net/9p/client.c:282 [inline] p9_req_put+0xaf/0x250 net/9p/client.c:279 req_done+0x1dc/0x2e0 net/9p/trans_virtio.c:147 vring_interrupt+0x2cf/0x440 drivers/virtio/virtio_ring.c:2718 __handle_irq_event_percpu+0x236/0x890 kernel/irq/handle.c:211 handle_irq_event_percpu kernel/irq/handle.c:248 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:265 handle_edge_irq+0x3ca/0x9e0 kernel/irq/chip.c:855 generic_handle_irq_desc include/linux/irqdesc.h:172 [inline] handle_irq arch/x86/kernel/irq.c:255 [inline] call_irq_handler arch/x86/kernel/irq.c:311 [inline] __common_interrupt+0xd0/0x2f0 arch/x86/kernel/irq.c:326 common_interrupt+0xba/0xe0 arch/x86/kernel/irq.c:319 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688 RIP: 0010:kvm_hypercall1 arch/x86/include/asm/kvm_para.h:59 [inline] RIP: 0010:kvm_smp_send_call_func_ipi+0x1e5/0x250 arch/x86/kernel/kvm.c:645 Code: 00 fc ff df 48 89 da 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 5d 8b 1b b8 0b 00 00 00 0f 01 c1 3a ff ff ff e8 c1 b9 52 00 90 0f 0b 48 89 df e8 86 97 bb 00 e9 RSP: 0018:ffffc900046df7d0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff816bb0af RDX: 0000000000000000 RSI: ffffffff816bb0bd RDI: ffffffff8dd74f28 RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000001 R11: ffff8880236faff0 R12: fffffbfff1c45765 R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000001 arch_send_call_function_ipi_mask arch/x86/include/asm/smp.h:100 [inline] send_call_function_ipi_mask kernel/smp.c:129 [inline] smp_call_function_many_cond+0xcdf/0x15e0 kernel/smp.c:859 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline] smp_text_poke_batch_finish+0x5ad/0xdb0 arch/x86/kernel/alternative.c:2983 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x376/0x550 kernel/jump_label.c:919 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate mm/kfence/core.c:874 [inline] toggle_allocation_gate+0xfa/0x280 mm/kfence/core.c:866 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 29403: kasan_save_stack+0x33/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:957 [inline] p9_client_create+0xae/0xe40 net/9p/client.c:862 v9fs_session_init+0x40/0xd40 fs/9p/v9fs.c:442 v9fs_get_tree+0xb8/0xb50 fs/9p/vfs_super.c:97 vfs_get_tree+0x8e/0x330 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount fs/namespace.c:3712 [inline] path_mount+0x7bf/0x23a0 fs/namespace.c:4022 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount fs/namespace.c:4201 [inline] __ia32_sys_mount+0x291/0x310 fs/namespace.c:4201 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe8/0x680 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 29403: kasan_save_stack+0x33/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kfree+0x2f8/0x6e0 mm/slub.c:6878 p9_client_create+0x6c5/0xe40 net/9p/client.c:941 v9fs_session_init+0x40/0xd40 fs/9p/v9fs.c:442 v9fs_get_tree+0xb8/0xb50 fs/9p/vfs_super.c:97 vfs_get_tree+0x8e/0x330 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount fs/namespace.c:3712 [inline] path_mount+0x7bf/0x23a0 fs/namespace.c:4022 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount fs/namespace.c:4201 [inline] __ia32_sys_mount+0x291/0x310 fs/namespace.c:4201 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe8/0x680 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff8880445ee400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff8880445ee400, ffff8880445ee600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x445ec head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff88801b442c80 ffffea0001311000 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff88801b442c80 ffffea0001311000 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 04fff00000000002 ffffea0001117b01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 20326377976, free_ts 18737992670 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1857 prep_new_page mm/page_alloc.c:1865 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4656 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x485/0x800 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] device_private_init drivers/base/core.c:3534 [inline] device_add+0xcf2/0x1980 drivers/base/core.c:3585 usb_hub_create_port_device+0x3a1/0xde0 drivers/usb/core/port.c:769 hub_configure drivers/usb/core/hub.c:1734 [inline] hub_probe+0x203b/0x36c0 drivers/usb/core/hub.c:2001 usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x7df/0x1170 mm/page_alloc.c:2943 discard_slab mm/slub.c:3346 [inline] __put_partials+0x130/0x170 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] __kmalloc_cache_noprof+0x282/0x800 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] device_private_init drivers/base/core.c:3534 [inline] device_add+0xcf2/0x1980 drivers/base/core.c:3585 usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695 register_root_hub+0x299/0x750 drivers/usb/core/hcd.c:994 usb_add_hcd+0xaf2/0x1780 drivers/usb/core/hcd.c:2993 dummy_hcd_probe+0x15c/0x380 drivers/usb/gadget/udc/dummy_hcd.c:2694 platform_probe+0x106/0x1d0 drivers/base/platform.c:1446 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 Memory state around the buggy address: ffff8880445ee300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880445ee380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880445ee400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880445ee480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880445ee500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 48 89 da mov %rbx,%rdx 3: 48 c1 ea 03 shr $0x3,%rdx 7: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx b: 48 89 d8 mov %rbx,%rax e: 83 e0 07 and $0x7,%eax 11: 83 c0 03 add $0x3,%eax 14: 38 d0 cmp %dl,%al 16: 7c 04 jl 0x1c 18: 84 d2 test %dl,%dl 1a: 75 5d jne 0x79 1c: 8b 1b mov (%rbx),%ebx 1e: b8 0b 00 00 00 mov $0xb,%eax 23: 0f 01 c1 vmcall * 26: e9 3a ff ff ff jmp 0xffffff65 <-- trapping instruction 2b: e8 c1 b9 52 00 call 0x52b9f1 30: 90 nop 31: 0f 0b ud2 33: 48 89 df mov %rbx,%rdi 36: e8 86 97 bb 00 call 0xbb97c1 3b: e9 .byte 0xe9