====================================== | xx__-> [ 2.534727] ------------[ cut here ]------------ | [ 2.534936] refcount_t: underflow; use-after-free. | [ 2.535100] WARNING: CPU: 2 PID: 280 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 2.535200] Modules linked in: bridge stp llc veth [ 2.535374] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 2.535496] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 2.535561] Code: 8e 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 d1 8e 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: 8e e8 mov %eax,%gs 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 d1 8e mov $0xffffffff8ed1e028,%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 [ 2.535723] RSP: 0018:ffffb3fd4029b730 EFLAGS: 00010282 [ 2.535786] RAX: 0000000000000000 RBX: ffffb3fd4029b740 RCX: 00000000ffffdfff [ 2.535867] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 2.535950] RBP: ffffb3fd4029b248 R08: ffffffff8f156a28 R09: 00000000ffffdfff [ 2.536045] R10: ffffffff8f076a40 R11: ffffffff8f126a40 R12: dead000000000122 [ 2.536135] R13: 00000000fffb7588 R14: 0000000000000001 R15: ffff97c28112d000 [ 2.536250] FS: 00007f7d9fd6f800(0000) GS:ffff97c32f4d9000(0000) knlGS:0000000000000000 [ 2.536329] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.536402] CR2: 00007f6a9b578998 CR3: 0000000005abc001 CR4: 0000000000772ef0 [ 2.536484] PKRU: 55555554 [ 2.536524] Call Trace: [ 2.536565] [ 2.536604] netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670) [ 2.536664] rtnl_dellink (net/core/rtnetlink.c:3580) [ 2.536754] ? virtio_fs_enqueue_req (fs/fuse/virtio_fs.c:1473) [ 2.536813] ? netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11653) [ 2.536869] ? rtnl_bridge_getlink (net/core/rtnetlink.c:3536) [ 2.536926] rtnetlink_rcv_msg (net/core/rtnetlink.c:6959) [ 2.536983] ? get_page_from_freelist (mm/page_alloc.c:1226 mm/page_alloc.c:1848 mm/page_alloc.c:1858 mm/page_alloc.c:3884) [ 2.537049] ? rtnl_calcit.isra.0 (net/core/rtnetlink.c:6861) [ 2.537113] netlink_rcv_skb (net/netlink/af_netlink.c:2550) [ 2.537177] netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) [ 2.537240] ? __alloc_skb (net/core/skbuff.c:690) [ 2.537319] netlink_sendmsg (net/netlink/af_netlink.c:1894) [ 2.537384] ____sys_sendmsg (net/socket.c:727 net/socket.c:742 net/socket.c:2630) [ 2.537442] ? copy_msghdr_from_user (net/socket.c:2570) [ 2.537505] ___sys_sendmsg (net/socket.c:2686) [ 2.537560] ? do_wp_page (./include/linux/mmu_notifier.h:468 mm/memory.c:3786 mm/memory.c:4140) [ 2.537619] ? ___pte_offset_map (./include/linux/pgtable.h:347 ./include/linux/pgtable.h:635 mm/pgtable-generic.c:288) [ 2.537692] ? nfulnl_rcv_nl_event (net/netfilter/nfnetlink_log.c:836) [ 2.537761] ? fsnotify_grab_connector (fs/notify/mark.c:709) [ 2.537826] ? fsnotify_destroy_marks (fs/notify/mark.c:937) [ 2.537923] __sys_sendmsg (net/socket.c:2716) [ 2.537989] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) [ 2.538072] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 2.538132] RIP: 0033:0x7f7d9ff3d1d7 [ 2.538188] 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) [ 2.538361] RSP: 002b:00007ffe6b79cd98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 2.538443] RAX: ffffffffffffffda RBX: 00007ffe6b79d4c0 RCX: 00007f7d9ff3d1d7 [ 2.538519] RDX: 0000000000000000 RSI: 00007ffe6b79ce00 RDI: 0000000000000005 [ 2.538595] RBP: 0000000000000002 R08: 0000000000000003 R09: 0000000000000078 [ 2.538688] R10: 00007f7d9fe39f60 R11: 0000000000000246 R12: 0000000000000002 Finger prints: refcount_warn_saturate:netdev_run_todo:rtnl_dellink:rtnetlink_rcv_msg:netlink_rcv_skb