================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2d90/0x3c40 kernel/locking/lockdep.c:5091 Read of size 8 at addr ffff888000538418 by task swapper/0/0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-syzkaller-09585-gb4b0881156fb #0 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+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 __lock_acquire+0x2d90/0x3c40 kernel/locking/lockdep.c:5091 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851 __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:397 [inline] p9_req_put net/9p/client.c:405 [inline] p9_req_put+0xaf/0x250 net/9p/client.c:402 req_done+0x1e7/0x2f0 net/9p/trans_virtio.c:147 vring_interrupt drivers/virtio/virtio_ring.c:2715 [inline] vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2690 __handle_irq_event_percpu+0x229/0x7d0 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+0x263/0xd10 kernel/irq/chip.c:831 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:handle_softirqs+0x1da/0x8f0 kernel/softirq.c:547 Code: 89 44 24 18 48 89 6c 24 10 48 c7 c7 e0 6c 6b 8b e8 cb 5c ca 09 65 66 c7 05 49 20 88 7e 00 00 e8 7c d1 44 00 fb bb ff ff ff ff <49> c7 c6 c0 b0 e0 8d 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1 RSP: 0018:ffffc90000007f28 EFLAGS: 00000202 RAX: 0000000000b88662 RBX: 00000000ffffffff RCX: 1ffffffff20bf011 RDX: 0000000000000000 RSI: ffffffff8b6ce540 RDI: ffffffff8bd2c2c0 RBP: ffffffff8de97740 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff905fc417 R11: 0000000000000001 R12: 0000000000000280 R13: 000000000000000a R14: 0000000000000001 R15: 0000000000000000 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:sched_core_balance+0xa0/0xd50 kernel/sched/core.c:6412 Code: c0 1b 8e e8 42 d5 0c 00 e8 5d a8 bc 09 41 5a 85 c0 0f 85 91 09 00 00 4c 89 e7 e8 6b ca fe ff e8 16 33 37 00 fb 48 63 44 24 50 <48> c7 c3 00 ed 03 00 48 83 f8 07 48 89 44 24 08 0f 87 fc 0b 00 00 RSP: 0018:ffffffff8de07b48 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff88802b43ed00 RCX: 1ffffffff20bf011 RDX: 0000000000000000 RSI: ffffffff8b6ce540 RDI: ffffffff8bd2c2c0 RBP: ffffffff8de07c60 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff905fc417 R11: 0000000000000000 R12: ffff88802b43ed00 R13: ffff888024da4880 R14: 0000000000000000 R15: 0000000000000000 do_balance_callbacks kernel/sched/core.c:5029 [inline] __balance_callbacks kernel/sched/core.c:5083 [inline] finish_lock_switch kernel/sched/core.c:5130 [inline] finish_task_switch.isra.0+0x46d/0xcc0 kernel/sched/core.c:5249 context_switch kernel/sched/core.c:5380 [inline] __schedule+0xf4b/0x5890 kernel/sched/core.c:6764 schedule_idle+0x5c/0x90 kernel/sched/core.c:6882 do_idle+0x284/0x3f0 kernel/sched/idle.c:353 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 rest_init+0x16b/0x2b0 init/main.c:743 start_kernel+0x3e9/0x4d0 init/main.c:1099 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:515 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:496 common_startup_64+0x13e/0x148 Allocated by task 19365: 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:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:901 [inline] p9_client_create+0xc8/0x11a0 net/9p/client.c:985 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410 v9fs_mount+0xc6/0xa30 fs/9p/vfs_super.c:122 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8b/0x340 fs/super.c:1814 do_new_mount fs/namespace.c:3560 [inline] path_mount+0x6e1/0x1f00 fs/namespace.c:3887 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __ia32_sys_mount+0x28d/0x310 fs/namespace.c:4088 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 19365: 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:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x2c4/0x4d0 mm/slub.c:4757 p9_client_create+0x97d/0x11a0 net/9p/client.c:1064 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410 v9fs_mount+0xc6/0xa30 fs/9p/vfs_super.c:122 legacy_get_tree+0x109/0x220 fs/fs_context.c:662 vfs_get_tree+0x8b/0x340 fs/super.c:1814 do_new_mount fs/namespace.c:3560 [inline] path_mount+0x6e1/0x1f00 fs/namespace.c:3887 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __ia32_sys_mount+0x28d/0x310 fs/namespace.c:4088 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff888000538400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff888000538400, ffff888000538600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x538 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0x7ff00000000040(head|node=0|zone=0|lastcpupid=0x7ff) page_type: f5(slab) raw: 007ff00000000040 ffff88801b042c80 ffffea000171fd00 dead000000000003 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 007ff00000000040 ffff88801b042c80 ffffea000171fd00 dead000000000003 head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 007ff00000000002 ffffea0000014e01 ffffffffffffffff 0000000000000000 head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 18156, tgid 18150 (syz.2.4000), ts 550565283673, free_ts 478263760565 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x221/0x2470 mm/page_alloc.c:4739 alloc_pages_mpol+0x1fc/0x540 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab mm/slub.c:2587 [inline] new_slab+0x23d/0x330 mm/slub.c:2640 ___slab_alloc+0xbfa/0x1600 mm/slub.c:3826 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_noprof+0x2de/0x4f0 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] bpf_map_meta_alloc+0x1a9/0x780 kernel/bpf/map_in_map.c:32 array_of_map_alloc+0x44/0xf0 kernel/bpf/arraymap.c:1359 map_create+0x5c5/0x1d30 kernel/bpf/syscall.c:1446 __sys_bpf+0x4f58/0x57a0 kernel/bpf/syscall.c:5776 __do_sys_bpf kernel/bpf/syscall.c:5901 [inline] __se_sys_bpf kernel/bpf/syscall.c:5899 [inline] __ia32_sys_bpf+0x76/0xe0 kernel/bpf/syscall.c:5899 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e page last free pid 29 tgid 29 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 pagetable_free include/linux/mm.h:2917 [inline] pagetable_dtor_free include/linux/mm.h:3015 [inline] __tlb_remove_table include/asm-generic/tlb.h:216 [inline] __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x116/0x1a0 mm/mmu_gather.c:282 rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2802 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 run_ksoftirqd kernel/softirq.c:950 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:942 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff888000538300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888000538380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888000538400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888000538480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888000538500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 89 44 24 18 mov %eax,0x18(%rsp) 4: 48 89 6c 24 10 mov %rbp,0x10(%rsp) 9: 48 c7 c7 e0 6c 6b 8b mov $0xffffffff8b6b6ce0,%rdi 10: e8 cb 5c ca 09 call 0x9ca5ce0 15: 65 66 c7 05 49 20 88 movw $0x0,%gs:0x7e882049(%rip) # 0x7e882068 1c: 7e 00 00 1f: e8 7c d1 44 00 call 0x44d1a0 24: fb sti 25: bb ff ff ff ff mov $0xffffffff,%ebx * 2a: 49 c7 c6 c0 b0 e0 8d mov $0xffffffff8de0b0c0,%r14 <-- 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