====================================== | xx__-> [ 23.814888] ------------[ cut here ]------------ | [ 23.815029] refcount_t: underflow; use-after-free. | [ 23.815123] WARNING: CPU: 2 PID: 475 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 23.815227] Modules linked in: vrf veth [ 23.815403] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 23.815492] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 23.815570] Code: 8c e8 18 df ba ff 90 0f 0b 90 90 c3 80 3d f9 da eb 00 00 75 89 c6 05 f0 da eb 00 01 90 48 c7 c7 28 e0 11 8c e8 f5 de ba ff 90 <0f> 0b 90 90 c3 80 3d d4 da eb 00 00 0f 85 62 ff ff ff c6 05 c7 da All code ======== 0: 8c e8 mov %gs,%eax 2: 18 df sbb %bl,%bh 4: ba ff 90 0f 0b mov $0xb0f90ff,%edx 9: 90 nop a: 90 nop b: c3 ret c: 80 3d f9 da eb 00 00 cmpb $0x0,0xebdaf9(%rip) # 0xebdb0c 13: 75 89 jne 0xffffffffffffff9e 15: c6 05 f0 da eb 00 01 movb $0x1,0xebdaf0(%rip) # 0xebdb0c 1c: 90 nop 1d: 48 c7 c7 28 e0 11 8c mov $0xffffffff8c11e028,%rdi 24: e8 f5 de ba ff call 0xffffffffffbadf1e 29: 90 nop 2a:* 0f 0b ud2 <-- trapping instruction 2c: 90 nop 2d: 90 nop 2e: c3 ret 2f: 80 3d d4 da eb 00 00 cmpb $0x0,0xebdad4(%rip) # 0xebdb0a 36: 0f 85 62 ff ff ff jne 0xffffffffffffff9e 3c: c6 .byte 0xc6 3d: 05 .byte 0x5 3e: c7 (bad) 3f: da .byte 0xda Code starting with the faulting instruction =========================================== 0: 0f 0b ud2 2: 90 nop 3: 90 nop 4: c3 ret 5: 80 3d d4 da eb 00 00 cmpb $0x0,0xebdad4(%rip) # 0xebdae0 c: 0f 85 62 ff ff ff jne 0xffffffffffffff74 12: c6 .byte 0xc6 13: 05 .byte 0x5 14: c7 (bad) 15: da .byte 0xda [ 23.815757] RSP: 0018:ffffad49809a7730 EFLAGS: 00010282 [ 23.815830] RAX: 0000000000000000 RBX: ffffad49809a7740 RCX: 00000000ffffdfff [ 23.815936] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 23.816030] RBP: ffffad49809a7248 R08: ffffffff8c556a28 R09: 00000000ffffdfff [ 23.816129] R10: ffffffff8c476a40 R11: ffffffff8c526a40 R12: dead000000000122 [ 23.816224] R13: 00000000fffbc8a0 R14: 0000000000000001 R15: ffff9d31c112c000 [ 23.816320] FS: 00007fe0a418e800(0000) GS:ffff9d32720d9000(0000) knlGS:0000000000000000 [ 23.816418] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 23.816501] CR2: 00000000004e5458 CR3: 00000000032d8003 CR4: 0000000000772ef0 [ 23.816595] PKRU: 55555554 [ 23.816642] Call Trace: [ 23.816695] [ 23.816742] netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670) [ 23.816811] rtnl_dellink (net/core/rtnetlink.c:3580) [ 23.816884] ? virtio_fs_enqueue_req (fs/fuse/virtio_fs.c:1473) [ 23.816963] ? netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11653) [ 23.817025] ? rtnl_bridge_getlink (net/core/rtnetlink.c:3536) [ 23.817097] rtnetlink_rcv_msg (net/core/rtnetlink.c:6959) [ 23.817158] ? get_page_from_freelist (mm/page_alloc.c:1226 mm/page_alloc.c:1848 mm/page_alloc.c:1858 mm/page_alloc.c:3884) [ 23.817234] ? rtnl_calcit.isra.0 (net/core/rtnetlink.c:6861) [ 23.817305] netlink_rcv_skb (net/netlink/af_netlink.c:2550) [ 23.817371] netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) [ 23.817432] ? __alloc_skb (net/core/skbuff.c:690) [ 23.817495] netlink_sendmsg (net/netlink/af_netlink.c:1894) [ 23.817556] ____sys_sendmsg (net/socket.c:727 net/socket.c:742 net/socket.c:2630) [ 23.817620] ? copy_msghdr_from_user (net/socket.c:2570) [ 23.817692] ___sys_sendmsg (net/socket.c:2686) [ 23.817754] ? do_wp_page (./include/linux/mmu_notifier.h:468 mm/memory.c:3786 mm/memory.c:4140) [ 23.817817] ? ___pte_offset_map (./include/linux/pgtable.h:347 ./include/linux/pgtable.h:635 mm/pgtable-generic.c:288) [ 23.817885] ? nfulnl_rcv_nl_event (net/netfilter/nfnetlink_log.c:836) [ 23.817966] ? fsnotify_grab_connector (fs/notify/mark.c:709) [ 23.818040] ? fsnotify_destroy_marks (fs/notify/mark.c:937) [ 23.818112] __sys_sendmsg (net/socket.c:2716) [ 23.818176] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) [ 23.818240] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 23.818313] RIP: 0033:0x7fe0a435c1d7 [ 23.818378] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 All code ======== 0: 0e (bad) 1: 00 f7 add %dh,%bh 3: d8 64 89 02 fsubs 0x2(%rcx,%rcx,4) 7: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax e: eb b9 jmp 0xffffffffffffffc9 10: 0f 1f 00 nopl (%rax) 13: f3 0f 1e fa endbr64 17: 64 8b 04 25 18 00 00 mov %fs:0x18,%eax 1e: 00 1f: 85 c0 test %eax,%eax 21: 75 10 jne 0x33 23: b8 2e 00 00 00 mov $0x2e,%eax 28: 0f 05 syscall 2a:* 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction 30: 77 51 ja 0x83 32: c3 ret 33: 48 83 ec 28 sub $0x28,%rsp 37: 89 54 24 1c mov %edx,0x1c(%rsp) 3b: 48 89 74 24 10 mov %rsi,0x10(%rsp) Code starting with the faulting instruction =========================================== 0: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax 6: 77 51 ja 0x59 8: c3 ret 9: 48 83 ec 28 sub $0x28,%rsp d: 89 54 24 1c mov %edx,0x1c(%rsp) 11: 48 89 74 24 10 mov %rsi,0x10(%rsp) [ 23.818567] RSP: 002b:00007ffd4b264df8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 23.818668] RAX: ffffffffffffffda RBX: 00007ffd4b265520 RCX: 00007fe0a435c1d7 [ 23.818761] RDX: 0000000000000000 RSI: 00007ffd4b264e60 RDI: 0000000000000005 [ 23.818863] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078 [ 23.818958] R10: 00007fe0a4258f60 R11: 0000000000000246 R12: 0000000000000002 Finger prints: refcount_warn_saturate:netdev_run_todo:rtnl_dellink:rtnetlink_rcv_msg:netlink_rcv_skb