================================================================== BUG: KASAN: slab-use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline] BUG: KASAN: slab-use-after-free in do_raw_spin_lock+0x26f/0x2b0 kernel/locking/spinlock_debug.c:115 Read of size 4 at addr ffff8880602d5804 by task swapper/0/0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 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 debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline] do_raw_spin_lock+0x26f/0x2b0 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162 p9_tag_remove net/9p/client.c:397 [inline] p9_req_put net/9p/client.c:405 [inline] p9_req_put+0xaf/0x250 net/9p/client.c:402 req_done+0x1dc/0x2e0 net/9p/trans_virtio.c:147 vring_interrupt drivers/virtio/virtio_ring.c:2719 [inline] vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2694 __handle_irq_event_percpu+0x22c/0x7d0 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x3ca/0x9e0 kernel/irq/chip.c:855 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:254 [inline] call_irq_handler arch/x86/kernel/irq.c:310 [inline] __common_interrupt+0xd0/0x2f0 arch/x86/kernel/irq.c:325 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:318 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:565 Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 e0 a5 ab 8b e8 68 a7 14 0a 65 66 c7 05 f6 d2 59 12 00 00 e8 d9 f0 46 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 20 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1 RSP: 0018:ffffc90000007f28 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 00000000ffffffff RCX: ffffffff81c2ed1f RDX: 0000000000000000 RSI: ffffffff8c162c80 RDI: ffffffff817bfd47 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff90ab7697 R11: 0000000000000000 R12: 0000000000000082 R13: 000000000000000a R14: 1ffff92000000fed R15: fffffbfff1c52ef8 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:sched_core_balance+0xa0/0xeb0 kernel/sched/core.c:6382 Code: 10 5c 8e e8 62 38 0d 00 e8 2d 69 06 0a 41 5b 85 c0 0f 85 31 0a 00 00 4c 89 e7 e8 7b 72 fe ff e8 06 c6 38 00 fb 48 63 44 24 50 <48> c7 c3 40 74 d7 93 48 89 44 24 08 48 83 f8 07 0f 87 9c 0c 00 00 RSP: 0018:ffffffff8e207b10 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88802b223f10 RCX: ffffffff81c2ed1f RDX: 0000000000000000 RSI: ffffffff8c162c80 RDI: ffffffff818a281a RBP: ffffffff8e207c30 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff90ab7697 R11: ffffffff818a27ed R12: ffff88802b23a440 R13: ffff888020698000 R14: 0000000000000000 R15: dffffc0000000000 do_balance_callbacks kernel/sched/core.c:5011 [inline] __balance_callbacks kernel/sched/core.c:5065 [inline] finish_lock_switch kernel/sched/core.c:5104 [inline] finish_task_switch.isra.0+0x46f/0xc10 kernel/sched/core.c:5223 context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1198/0x5de0 kernel/sched/core.c:6961 schedule_idle+0x5c/0x90 kernel/sched/core.c:7084 do_idle+0x2b6/0x510 kernel/sched/idle.c:358 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 rest_init+0x16b/0x2b0 init/main.c:744 start_kernel+0x3ee/0x4d0 init/main.c:1097 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148 Allocated by task 7734: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405 kmalloc_noprof include/linux/slab.h:905 [inline] p9_client_create+0xc7/0x11c0 net/9p/client.c:985 v9fs_session_init+0x1f7/0x1a80 fs/9p/v9fs.c:410 v9fs_mount+0xc5/0xa90 fs/9p/vfs_super.c:122 legacy_get_tree+0x10c/0x220 fs/fs_context.c:666 vfs_get_tree+0x8e/0x340 fs/super.c:1815 do_new_mount fs/namespace.c:3808 [inline] path_mount+0x1513/0x2000 fs/namespace.c:4123 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount fs/namespace.c:4324 [inline] __ia32_sys_mount+0x28b/0x310 fs/namespace.c:4324 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 7734: 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:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4879 p9_client_create+0xa28/0x11c0 net/9p/client.c:1064 v9fs_session_init+0x1f7/0x1a80 fs/9p/v9fs.c:410 v9fs_mount+0xc5/0xa90 fs/9p/vfs_super.c:122 legacy_get_tree+0x10c/0x220 fs/fs_context.c:666 vfs_get_tree+0x8e/0x340 fs/super.c:1815 do_new_mount fs/namespace.c:3808 [inline] path_mount+0x1513/0x2000 fs/namespace.c:4123 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount fs/namespace.c:4324 [inline] __ia32_sys_mount+0x28b/0x310 fs/namespace.c:4324 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff8880602d5800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 4 bytes inside of freed 512-byte region [ffff8880602d5800, ffff8880602d5a00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880602d4800 pfn:0x602d4 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 ffff88801b842c80 ffffea00013bd800 dead000000000002 raw: ffff8880602d4800 000000008010000d 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff88801b842c80 ffffea00013bd800 dead000000000002 head: ffff8880602d4800 000000008010000d 00000000f5000000 0000000000000000 head: 04fff00000000002 ffffea000180b501 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 5992, tgid 5992 (syz-executor), ts 104357363055, free_ts 104313695552 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab mm/slub.c:2655 [inline] new_slab+0x247/0x330 mm/slub.c:2709 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981 __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x14c/0x870 net/ipv6/route.c:3811 addrconf_f6i_alloc+0x2da/0x660 net/ipv6/route.c:4680 ipv6_add_addr+0x531/0x1fe0 net/ipv6/addrconf.c:1126 inet6_addr_add+0x256/0x960 net/ipv6/addrconf.c:3050 inet6_rtm_newaddr+0x1619/0x1c70 net/ipv6/addrconf.c:5059 rtnetlink_rcv_msg+0x95b/0xe90 net/core/rtnetlink.c:6946 netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552 page last free pid 5992 tgid 5992 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 stack_depot_save_flags+0x352/0x9c0 lib/stackdepot.c:727 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405 kmalloc_noprof include/linux/slab.h:905 [inline] netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:664 [inline] netdevice_event+0x365/0x9d0 drivers/infiniband/core/roce_gid_mgmt.c:823 notifier_call_chain+0xb9/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2229 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers+0x7c/0xb0 net/core/dev.c:2281 vlan_dev_inherit_address net/8021q/vlan_dev.c:256 [inline] vlan_dev_inherit_address net/8021q/vlan_dev.c:249 [inline] vlan_dev_open+0x535/0x6c0 net/8021q/vlan_dev.c:271 __dev_open+0x2e4/0x7c0 net/core/dev.c:1682 __dev_change_flags+0x55d/0x720 net/core/dev.c:9549 netif_change_flags+0x8d/0x160 net/core/dev.c:9612 dev_change_flags+0xba/0x250 net/core/dev_api.c:68 vlan_device_event+0x182c/0x2620 net/8021q/vlan.c:492 notifier_call_chain+0xb9/0x410 kernel/notifier.c:85 Memory state around the buggy address: ffff8880602d5700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880602d5780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880602d5800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880602d5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880602d5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 88 6c 24 26 mov %ch,0x26(%rsp) 4: 4c 89 7c 24 18 mov %r15,0x18(%rsp) 9: 48 c7 c7 e0 a5 ab 8b mov $0xffffffff8baba5e0,%rdi 10: e8 68 a7 14 0a call 0xa14a77d 15: 65 66 c7 05 f6 d2 59 movw $0x0,%gs:0x1259d2f6(%rip) # 0x1259d315 1c: 12 00 00 1f: e8 d9 f0 46 00 call 0x46f0fd 24: fb sti 25: bb ff ff ff ff mov $0xffffffff,%ebx * 2a: 49 c7 c7 c0 c0 20 8e mov $0xffffffff8e20c0c0,%r15 <-- trapping instruction 31: 41 0f bc dc bsf %r12d,%ebx 35: 83 c3 01 add $0x1,%ebx 38: 0f 85 a4 00 00 00 jne 0xe2 3e: e9 .byte 0xe9 3f: b1 .byte 0xb1