====================================== | [ 2.107142] ------------[ cut here ]------------ | [ 2.107260] refcount_t: underflow; use-after-free. | [ 2.107337] WARNING: CPU: 2 PID: 257 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 2.107428] Modules linked in: [ 2.107593] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 2.107669] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 2.107735] Code: b7 e8 88 98 ba ff 90 0f 0b 90 90 c3 80 3d 69 b4 eb 00 00 75 89 c6 05 60 b4 eb 00 01 90 48 c7 c7 98 6e f4 b7 e8 65 98 ba ff 90 <0f> 0b 90 90 c3 80 3d 44 b4 eb 00 00 0f 85 62 ff ff ff c6 05 37 b4 All code ======== 0: b7 e8 mov $0xe8,%bh 2: 88 98 ba ff 90 0f mov %bl,0xf90ffba(%rax) 8: 0b 90 90 c3 80 3d or 0x3d80c390(%rax),%edx e: 69 b4 eb 00 00 75 89 imul $0xb46005c6,-0x768b0000(%rbx,%rbp,8),%esi 15: c6 05 60 b4 19: eb 00 jmp 0x1b 1b: 01 90 48 c7 c7 98 add %edx,-0x673838b8(%rax) 21: 6e outsb %ds:(%rsi),(%dx) 22: f4 hlt 23: b7 e8 mov $0xe8,%bh 25: 65 98 gs cwtl 27:* ba ff 90 0f 0b mov $0xb0f90ff,%edx <-- trapping instruction 2c: 90 nop 2d: 90 nop 2e: c3 ret 2f: 80 3d 44 b4 eb 00 00 cmpb $0x0,0xebb444(%rip) # 0xebb47a 36: 0f 85 62 ff ff ff jne 0xffffffffffffff9e 3c: c6 .byte 0xc6 3d: 05 .byte 0x5 3e: 37 (bad) 3f: b4 .byte 0xb4 Code starting with the faulting instruction =========================================== 0: 0f 0b ud2 2: 90 nop 3: 90 nop 4: c3 ret 5: 80 3d 44 b4 eb 00 00 cmpb $0x0,0xebb444(%rip) # 0xebb450 c: 0f 85 62 ff ff ff jne 0xffffffffffffff74 12: c6 .byte 0xc6 13: 05 .byte 0x5 14: 37 (bad) 15: b4 .byte 0xb4 [ 2.107885] RSP: 0018:ffffb94e4061f730 EFLAGS: 00010282 [ 2.107953] RAX: 0000000000000000 RBX: ffffb94e4061f740 RCX: 00000000ffffdfff [ 2.108037] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 2.108129] RBP: ffffb94e4061f258 R08: ffffffffb8356a28 R09: 00000000ffffdfff [ 2.108208] R10: ffffffffb8276a40 R11: ffffffffb8326a40 R12: dead000000000122 [ 2.108290] R13: 00000000fffb73cb R14: 0000000000000001 R15: ffff913082ce1000 [ 2.108378] FS: 00007fb5677fa800(0000) GS:ffff9131062b7000(0000) knlGS:0000000000000000 [ 2.108464] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.108537] CR2: 00007efe1234aeb0 CR3: 00000000051c6002 CR4: 0000000000772ef0 [ 2.108622] PKRU: 55555554 [ 2.108668] Call Trace: [ 2.108717] [ 2.108767] netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670) [ 2.108833] rtnl_dellink (net/core/rtnetlink.c:3580) [ 2.108890] ? virtio_fs_enqueue_req (fs/fuse/virtio_fs.c:1473) [ 2.108967] ? netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11653) [ 2.109022] ? rtnl_bridge_getlink (net/core/rtnetlink.c:3536) [ 2.109085] rtnetlink_rcv_msg (net/core/rtnetlink.c:6959) [ 2.109140] ? get_page_from_freelist (mm/page_alloc.c:1226 mm/page_alloc.c:1848 mm/page_alloc.c:1858 mm/page_alloc.c:3884) [ 2.109212] ? rtnl_calcit.isra.0 (net/core/rtnetlink.c:6861) [ 2.109280] netlink_rcv_skb (net/netlink/af_netlink.c:2550) [ 2.109337] netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) [ 2.109392] ? __alloc_skb (net/core/skbuff.c:690) [ 2.109452] netlink_sendmsg (net/netlink/af_netlink.c:1894) [ 2.109501] ____sys_sendmsg (net/socket.c:727 net/socket.c:742 net/socket.c:2630) [ 2.109562] ? copy_msghdr_from_user (net/socket.c:2570) [ 2.109629] ___sys_sendmsg (net/socket.c:2686) [ 2.109678] ? do_wp_page (./include/linux/mmu_notifier.h:468 mm/memory.c:3786 mm/memory.c:4140) [ 2.109737] ? __handle_mm_fault (mm/memory.c:6193 mm/memory.c:6318) [ 2.109799] ? fsnotify_grab_connector (fs/notify/mark.c:709) [ 2.109860] ? fsnotify_destroy_marks (fs/notify/mark.c:937) [ 2.109918] __sys_sendmsg (net/socket.c:2716) [ 2.109978] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) [ 2.110041] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 2.110113] RIP: 0033:0x7fb5679c81d7 [ 2.110165] 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) [ 2.110316] RSP: 002b:00007ffeab66feb8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 2.110394] RAX: ffffffffffffffda RBX: 00007ffeab6705e0 RCX: 00007fb5679c81d7 [ 2.110466] RDX: 0000000000000000 RSI: 00007ffeab66ff20 RDI: 0000000000000005 [ 2.110539] RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000078 [ 2.110627] R10: 00007fb5678c4f60 R11: 0000000000000246 R12: 0000000000000001 Finger prints: refcount_warn_saturate:netdev_run_todo:rtnl_dellink:rtnetlink_rcv_msg:netlink_rcv_skb