================================================================== BUG: KASAN: slab-use-after-free in __lock_acquire+0x2d90/0x3c40 kernel/locking/lockdep.c:5089 Read of size 8 at addr ffff88802add8818 by task syz.1.87/6330 CPU: 0 UID: 0 PID: 6330 Comm: syz.1.87 Not tainted 6.13.0-rc7-syzkaller-00019-gc45323b7560e #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:5089 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __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+0xba/0xe0 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 41 59 f6 48 89 df e8 fe c0 59 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 25 b1 4a f6 65 8b 05 96 d2 e6 74 85 c0 74 16 5b RSP: 0018:ffffc9000e07f7d8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffff8880678de1c0 RCX: 1ffffffff2d40dde RDX: 0000000000000000 RSI: ffffffff8b4cd300 RDI: ffffffff8bb172c0 RBP: 0000000000000286 R08: 0000000000000001 R09: fffffbfff2d373b0 R10: ffffffff969b9d87 R11: 0000000000000004 R12: 0000000000000002 R13: ffff8880678de200 R14: ffff8880678ddba8 R15: ffff8880678de028 __unix_dgram_recvmsg+0x32a/0xf50 net/unix/af_unix.c:2463 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2538 sock_recvmsg_nosec net/socket.c:1033 [inline] ____sys_recvmsg+0x5f8/0x6b0 net/socket.c:2801 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2845 do_recvmmsg+0x55d/0x740 net/socket.c:2932 __sys_recvmmsg+0x21e/0x280 net/socket.c:3014 __do_compat_sys_recvmmsg_time32 net/compat.c:418 [inline] __se_compat_sys_recvmmsg_time32 net/compat.c:414 [inline] __ia32_compat_sys_recvmmsg_time32+0xc4/0x160 net/compat.c:414 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 RIP: 0023:0xf7fe2579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f511555c EFLAGS: 00000296 ORIG_RAX: 0000000000000151 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000200000c0 RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6331: 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+0x8f/0x380 fs/super.c:1814 do_new_mount fs/namespace.c:3511 [inline] path_mount+0x6e1/0x1f00 fs/namespace.c:3838 do_mount fs/namespace.c:3851 [inline] __do_sys_mount fs/namespace.c:4061 [inline] __se_sys_mount fs/namespace.c:4038 [inline] __ia32_sys_mount+0x292/0x310 fs/namespace.c:4038 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 6331: 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:582 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:4613 [inline] kfree+0x14f/0x4b0 mm/slub.c:4761 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+0x8f/0x380 fs/super.c:1814 do_new_mount fs/namespace.c:3511 [inline] path_mount+0x6e1/0x1f00 fs/namespace.c:3838 do_mount fs/namespace.c:3851 [inline] __do_sys_mount fs/namespace.c:4061 [inline] __se_sys_mount fs/namespace.c:4038 [inline] __ia32_sys_mount+0x292/0x310 fs/namespace.c:4038 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 ffff88802add8800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 24 bytes inside of freed 512-byte region [ffff88802add8800, ffff88802add8a00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2add8 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801ac42c80 0000000000000000 dead000000000001 head: 0000000000000000 0000000080100010 00000001f5000000 0000000000000000 head: 00fff00000000002 ffffea0000ab7601 ffffffffffffffff 0000000000000000 head: ffff888000000004 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 5955, tgid 5955 (udevd), ts 55989514924, free_ts 55970713192 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3476 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4753 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_slab_page mm/slub.c:2425 [inline] allocate_slab mm/slub.c:2589 [inline] new_slab+0xca/0x410 mm/slub.c:2642 ___slab_alloc+0xce2/0x1650 mm/slub.c:3830 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_node_noprof+0x2f0/0x520 mm/slub.c:4304 kmalloc_array_node_noprof include/linux/slab.h:1018 [inline] alloc_slab_obj_exts+0x41/0xa0 mm/slub.c:1964 account_slab mm/slub.c:2552 [inline] allocate_slab mm/slub.c:2607 [inline] new_slab+0x314/0x410 mm/slub.c:2642 ___slab_alloc+0xce2/0x1650 mm/slub.c:3830 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] kmem_cache_alloc_noprof+0xeb/0x3b0 mm/slub.c:4175 sigqueue_alloc kernel/signal.c:454 [inline] __send_signal_locked+0x159/0x11a0 kernel/signal.c:1086 do_send_sig_info kernel/signal.c:1268 [inline] group_send_sig_info+0x2aa/0x300 kernel/signal.c:1418 bpf_send_signal_common+0x415/0x520 kernel/trace/bpf_trace.c:881 ____bpf_send_signal kernel/trace/bpf_trace.c:886 [inline] bpf_send_signal+0x1d/0x30 kernel/trace/bpf_trace.c:884 page last free pid 980 tgid 980 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0x661/0x1080 mm/page_alloc.c:2659 stack_depot_save_flags+0x30e/0x9e0 lib/stackdepot.c:674 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:582 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:4613 [inline] kmem_cache_free+0x152/0x4c0 mm/slub.c:4715 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2823 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 do_softirq kernel/softirq.c:462 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:449 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:389 local_bh_enable include/linux/bottom_half.h:33 [inline] update_defense_level+0x5ce/0xf50 net/netfilter/ipvs/ip_vs_ctl.c:210 defense_work_handler+0x26/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:235 process_one_work+0x958/0x1b30 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c1/0x3a0 kernel/kthread.c:389 Memory state around the buggy address: ffff88802add8700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802add8780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802add8800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802add8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802add8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: f5 cmc 1: 53 push %rbx 2: 48 8b 74 24 10 mov 0x10(%rsp),%rsi 7: 48 89 fb mov %rdi,%rbx a: 48 83 c7 18 add $0x18,%rdi e: e8 b6 41 59 f6 call 0xf65941c9 13: 48 89 df mov %rbx,%rdi 16: e8 fe c0 59 f6 call 0xf659c119 1b: f7 c5 00 02 00 00 test $0x200,%ebp 21: 75 23 jne 0x46 23: 9c pushf 24: 58 pop %rax 25: f6 c4 02 test $0x2,%ah 28: 75 37 jne 0x61 * 2a: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction 2f: e8 25 b1 4a f6 call 0xf64ab159 34: 65 8b 05 96 d2 e6 74 mov %gs:0x74e6d296(%rip),%eax # 0x74e6d2d1 3b: 85 c0 test %eax,%eax 3d: 74 16 je 0x55 3f: 5b pop %rbx