====================================== | [ 15.747688] ------------[ cut here ]------------ | [ 15.747857] refcount_t: underflow; use-after-free. | [ 15.747955] WARNING: CPU: 2 PID: 308 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 15.748047] Modules linked in: act_gact act_mirred cls_flower sch_ingress ip_gre gre 8021q vrf veth [ 15.748228] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 15.748299] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 15.748361] Code: b8 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 b8 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: b8 e8 18 df ba mov $0xbadf18e8,%eax 5: ff 90 0f 0b 90 90 call *-0x6f6ff4f1(%rax) 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 b8 mov $0xffffffffb8d1e028,%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 [ 15.748549] RSP: 0018:ffffb26d405c7730 EFLAGS: 00010282 [ 15.748632] RAX: 0000000000000000 RBX: ffffb26d405c7740 RCX: 00000000ffffdfff [ 15.748716] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 15.748810] RBP: ffffb26d405c7248 R08: ffffffffb9156a28 R09: 00000000ffffdfff [ 15.748903] R10: ffffffffb9076a40 R11: ffffffffb9126a40 R12: dead000000000122 [ 15.748990] R13: 00000000fffba91e R14: 0000000000000001 R15: ffff9035c33ab000 [ 15.749074] FS: 00007f502e830b80(0000) GS:ffff9036454d9000(0000) knlGS:0000000000000000 [ 15.749152] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.749224] CR2: 0000559124767190 CR3: 000000000614f004 CR4: 0000000000772ef0 [ 15.749332] PKRU: 55555554 [ 15.749379] Call Trace: [ 15.749425] [ 15.749469] netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670) [ 15.749538] rtnl_dellink (net/core/rtnetlink.c:3580) [ 15.749612] ? kmem_cache_alloc_node_noprof (./include/linux/kernel.h:61 ./include/linux/sched/mm.h:321 mm/slub.c:4921 mm/slub.c:5256 mm/slub.c:5332) [ 15.749688] ? finish_task_switch.isra.0 (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 kernel/sched/sched.h:1559 kernel/sched/core.c:5073 kernel/sched/core.c:5191) [ 15.749758] ? kmalloc_reserve (net/core/skbuff.c:586 (discriminator 2)) [ 15.749817] ? kmalloc_reserve (net/core/skbuff.c:586 (discriminator 2)) [ 15.749872] ? rtnl_bridge_getlink (net/core/rtnetlink.c:3536) [ 15.749947] rtnetlink_rcv_msg (net/core/rtnetlink.c:6959) [ 15.750013] ? netlink_unicast (net/netlink/af_netlink.c:1269 net/netlink/af_netlink.c:1359) [ 15.750071] ? rtnl_calcit.isra.0 (net/core/rtnetlink.c:6861) [ 15.750134] netlink_rcv_skb (net/netlink/af_netlink.c:2550) [ 15.750190] netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344) [ 15.750257] ? __alloc_skb (net/core/skbuff.c:690) [ 15.750325] netlink_sendmsg (net/netlink/af_netlink.c:1894) [ 15.750381] ____sys_sendmsg (net/socket.c:727 net/socket.c:742 net/socket.c:2630) [ 15.750438] ? copy_msghdr_from_user (net/socket.c:2570) [ 15.750503] ___sys_sendmsg (net/socket.c:2686) [ 15.750560] ? __handle_mm_fault (mm/memory.c:5690 mm/memory.c:5832 mm/memory.c:4361 mm/memory.c:6177 mm/memory.c:6318) [ 15.750633] ? anon_pipe_write (fs/pipe.c:598) [ 15.750690] __sys_sendmsg (net/socket.c:2716) [ 15.750751] do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) [ 15.750819] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) [ 15.750899] RIP: 0033:0x7f502e9711d7 [ 15.750965] 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) [ 15.751103] RSP: 002b:00007fff0c3d9af8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 15.751180] RAX: ffffffffffffffda RBX: 0000000040334320 RCX: 00007f502e9711d7 [ 15.751255] RDX: 0000000000000000 RSI: 00007fff0c3d9b30 RDI: 0000000000000005 [ 15.751330] RBP: 0000000040334230 R08: 0000000000000003 R09: 0000000000000000 [ 15.751406] R10: 0000000000000200 R11: 0000000000000246 R12: 0000000040344950 Finger prints: refcount_warn_saturate:netdev_run_todo:rtnl_dellink:rtnetlink_rcv_msg:netlink_rcv_skb