====================================== | [ 1318.251145] ------------[ cut here ]------------ | [ 1318.251661] refcount_t: underflow; use-after-free. | [ 1318.252229] WARNING: CPU: 2 PID: 68 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 1318.253138] Modules linked in: xt_conntrack nf_conntrack nf_defrag_ipv4 nf_defrag_ipv6 nft_compat nf_tables libcrc32c vxlan ip6_udp_tunnel udp_tunnel mpls_iptunnel mpls_router [ 1318.255614] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 1318.256283] Workqueue: netns cleanup_net [ 1318.256548] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 1318.256817] Code: 0b 90 90 c3 cc cc cc cc 80 3d 69 d4 67 01 00 0f 85 75 ff ff ff c6 05 5c d4 67 01 01 90 48 c7 c7 b8 37 13 9f e8 a1 26 b4 ff 90 <0f> 0b 90 90 c3 cc cc cc cc 80 3d 3c d4 67 01 00 0f 85 4a ff ff ff All code ======== 0: 0b 90 90 c3 cc cc or -0x33333c70(%rax),%edx 6: cc int3 7: cc int3 8: 80 3d 69 d4 67 01 00 cmpb $0x0,0x167d469(%rip) # 0x167d478 f: 0f 85 75 ff ff ff jne 0xffffffffffffff8a 15: c6 05 5c d4 67 01 01 movb $0x1,0x167d45c(%rip) # 0x167d478 1c: 90 nop 1d: 48 c7 c7 b8 37 13 9f mov $0xffffffff9f1337b8,%rdi 24: e8 a1 26 b4 ff call 0xffffffffffb426ca 29: 90 nop 2a:* 0f 0b ud2 <-- trapping instruction 2c: 90 nop 2d: 90 nop 2e: c3 ret 2f: cc int3 30: cc int3 31: cc int3 32: cc int3 33: 80 3d 3c d4 67 01 00 cmpb $0x0,0x167d43c(%rip) # 0x167d476 3a: 0f 85 4a ff ff ff jne 0xffffffffffffff8a Code starting with the faulting instruction =========================================== 0: 0f 0b ud2 2: 90 nop 3: 90 nop 4: c3 ret 5: cc int3 6: cc int3 7: cc int3 8: cc int3 9: 80 3d 3c d4 67 01 00 cmpb $0x0,0x167d43c(%rip) # 0x167d44c 10: 0f 85 4a ff ff ff jne 0xffffffffffffff60 [ 1318.258313] RSP: 0018:ffffbcdb40263d78 EFLAGS: 00010286 [ 1318.258674] RAX: 0000000000000000 RBX: ffff9e364290a000 RCX: 00000000ffffdfff [ 1318.259307] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 1318.260079] RBP: ffff9e364290a610 R08: ffffffff9f578508 R09: 00000000ffffdfff [ 1318.260782] R10: ffffffff9f498520 R11: ffffffff9f548520 R12: ffff9e364290a000 [ 1318.261647] R13: ffffbcdb40263e08 R14: ffff9e364290ab80 R15: ffff9e3643c45c50 [ 1318.262432] FS: 0000000000000000(0000) GS:ffff9e367ed00000(0000) knlGS:0000000000000000 [ 1318.263273] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1318.263903] CR2: 00007f3f76cc8000 CR3: 000000000f460005 CR4: 0000000000770ef0 [ 1318.264579] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1318.265359] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1318.266160] PKRU: 55555554 [ 1318.266485] Call Trace: [ 1318.266733] <TASK> [ 1318.266977] ? __warn (kernel/panic.c:677) [ 1318.267377] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 1318.267889] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 1318.268224] ? handle_bug (arch/x86/kernel/traps.c:238) [ 1318.268629] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 1318.269074] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 1318.269549] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 1318.269961] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 1318.270396] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) [ 1318.270864] br_dev_delete (net/bridge/br_if.c:396) [ 1318.271224] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 1318.271676] cleanup_net (net/core/net_namespace.c:630) [ 1318.272002] ? process_one_work (kernel/workqueue.c:2606) [ 1318.272390] process_one_work (kernel/workqueue.c:2633) [ 1318.272760] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 1318.273119] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 1318.273508] kthread (kernel/kthread.c:388) [ 1318.273806] ? __pfx_kthread (kernel/kthread.c:341) [ 1318.274105] ret_from_fork (arch/x86/kernel/process.c:147) [ 1318.274458] ? __pfx_kthread (kernel/kthread.c:341) [ 1318.274847] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) | [ 1318.278302] ------------[ cut here ]------------ | [ 1318.278560] sysfs group 'bridge' not found for kobject 'br0' | [ 1318.278876] WARNING: CPU: 0 PID: 68 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) | [ 1318.279345] Modules linked in: xt_conntrack nf_conntrack nf_defrag_ipv4 nf_defrag_ipv6 nft_compat nf_tables libcrc32c vxlan ip6_udp_tunnel udp_tunnel mpls_iptunnel mpls_router [ 1318.280751] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 1318.281386] Workqueue: netns cleanup_net [ 1318.281647] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 1318.281970] Code: 48 89 ef 5d 41 5c e9 7a ad ff ff 48 89 ef e8 12 9b ff ff eb d1 90 49 8b 14 24 48 8b 33 48 c7 c7 a0 cd 12 9f e8 ac 67 c5 ff 90 <0f> 0b 90 90 5b 5d 41 5c c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 All code ======== 0: 48 89 ef mov %rbp,%rdi 3: 5d pop %rbp 4: 41 5c pop %r12 6: e9 7a ad ff ff jmp 0xffffffffffffad85 b: 48 89 ef mov %rbp,%rdi e: e8 12 9b ff ff call 0xffffffffffff9b25 13: eb d1 jmp 0xffffffffffffffe6 15: 90 nop 16: 49 8b 14 24 mov (%r12),%rdx 1a: 48 8b 33 mov (%rbx),%rsi 1d: 48 c7 c7 a0 cd 12 9f mov $0xffffffff9f12cda0,%rdi 24: e8 ac 67 c5 ff call 0xffffffffffc567d5 29: 90 nop 2a:* 0f 0b ud2 <-- trapping instruction 2c: 90 nop 2d: 90 nop 2e: 5b pop %rbx 2f: 5d pop %rbp 30: 41 5c pop %r12 32: c3 ret 33: cc int3 34: cc int3 35: cc int3 36: cc int3 37: 66 data16 38: 66 data16 39: 2e cs 3a: 0f .byte 0xf 3b: 1f (bad) 3c: 84 00 test %al,(%rax) ... Code starting with the faulting instruction =========================================== 0: 0f 0b ud2 2: 90 nop 3: 90 nop 4: 5b pop %rbx 5: 5d pop %rbp 6: 41 5c pop %r12 8: c3 ret 9: cc int3 a: cc int3 b: cc int3 c: cc int3 d: 66 data16 e: 66 data16 f: 2e cs 10: 0f .byte 0xf 11: 1f (bad) 12: 84 00 test %al,(%rax) ... [ 1318.282930] RSP: 0018:ffffbcdb40263d70 EFLAGS: 00010286 [ 1318.283278] RAX: 0000000000000000 RBX: ffffffff9ed472c0 RCX: 00000000ffffdfff [ 1318.283686] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 1318.284130] RBP: 0000000000000000 R08: ffffffff9f578508 R09: 00000000ffffdfff [ 1318.284536] R10: ffffffff9f498520 R11: ffffffff9f548520 R12: ffff9e364290a610 [ 1318.284929] R13: ffffbcdb40263e08 R14: ffff9e364290ab80 R15: ffff9e3643c45c50 [ 1318.285372] FS: 0000000000000000(0000) GS:ffff9e367ec00000(0000) knlGS:0000000000000000 [ 1318.285885] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1318.286237] CR2: 00007f54d103f000 CR3: 000000000f460004 CR4: 0000000000770ef0 [ 1318.286649] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1318.287054] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1318.287461] PKRU: 55555554 [ 1318.287669] Call Trace: [ 1318.287848] <TASK> [ 1318.288008] ? __warn (kernel/panic.c:677) [ 1318.288245] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 1318.288509] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 1318.288755] ? handle_bug (arch/x86/kernel/traps.c:238) [ 1318.288984] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 1318.289207] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 1318.289434] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 1318.289695] br_dev_delete (net/bridge/br_if.c:396) [ 1318.289959] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 1318.290249] cleanup_net (net/core/net_namespace.c:630) [ 1318.290463] ? process_one_work (kernel/workqueue.c:2606) [ 1318.290685] process_one_work (kernel/workqueue.c:2633) [ 1318.290904] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 1318.291104] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 1318.291388] kthread (kernel/kthread.c:388) [ 1318.291661] ? __pfx_kthread (kernel/kthread.c:341) [ 1318.291884] ret_from_fork (arch/x86/kernel/process.c:147) [ 1318.292111] ? __pfx_kthread (kernel/kthread.c:341) Finger prints: refcount_warn_saturate:br_sysfs_delbr:br_dev_delete:br_net_exit_batch_rtnl sysfs_remove_group:br_dev_delete:br_net_exit_batch_rtnl:cleanup_net