====================================== | [ 30.868358] ------------[ cut here ]------------ | [ 30.868636] refcount_t: underflow; use-after-free. | [ 30.869002] WARNING: CPU: 1 PID: 11 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 30.869436] Modules linked in: xfrm_user psample macsec fou vxlan ip6_udp_tunnel udp_tunnel ip6_gre ip_gre gre cls_u32 sch_htb [last unloaded: netdevsim] [ 30.870538] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 30.871149] Workqueue: netns cleanup_net [ 30.871362] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 30.871643] 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 d3 aa 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 d3 aa mov $0xffffffffaad337b8,%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 [ 30.872620] RSP: 0018:ffffbd8c40063d78 EFLAGS: 00010286 [ 30.872919] RAX: 0000000000000000 RBX: ffff94878233a000 RCX: 00000000ffffdfff [ 30.873289] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 30.873656] RBP: ffff94878233a610 R08: ffffffffab178508 R09: 00000000ffffdfff [ 30.874040] R10: ffffffffab098520 R11: ffffffffab148520 R12: ffff94878233a000 [ 30.874407] R13: ffffbd8c40063e08 R14: ffff94878233ab80 R15: ffffffffac678f90 [ 30.874787] FS: 0000000000000000(0000) GS:ffff9487bec80000(0000) knlGS:0000000000000000 [ 30.875213] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.875514] CR2: 000055bf2918edec CR3: 0000000005e5a002 CR4: 0000000000770ef0 [ 30.875895] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.876261] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.876628] PKRU: 55555554 [ 30.876780] Call Trace: [ 30.876928] <TASK> [ 30.877049] ? __warn (kernel/panic.c:677) [ 30.877225] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 30.877473] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 30.877675] ? handle_bug (arch/x86/kernel/traps.c:238) [ 30.877882] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 30.878089] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 30.878318] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 30.878563] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 30.878830] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) [ 30.879043] br_dev_delete (net/bridge/br_if.c:396) [ 30.879240] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 30.879474] cleanup_net (net/core/net_namespace.c:630) [ 30.879671] ? process_one_work (kernel/workqueue.c:2606) [ 30.879914] process_one_work (kernel/workqueue.c:2633) [ 30.880129] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 30.880329] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 30.880559] kthread (kernel/kthread.c:388) [ 30.880732] ? __pfx_kthread (kernel/kthread.c:341) [ 30.880958] ret_from_fork (arch/x86/kernel/process.c:147) [ 30.881167] ? __pfx_kthread (kernel/kthread.c:341) [ 30.881472] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) | [ 30.884336] ------------[ cut here ]------------ | [ 30.884729] sysfs group 'bridge' not found for kobject 'test-br0' | [ 30.885250] WARNING: CPU: 2 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) | [ 30.885886] Modules linked in: xfrm_user psample macsec fou vxlan ip6_udp_tunnel udp_tunnel ip6_gre ip_gre gre cls_u32 sch_htb [last unloaded: netdevsim] [ 30.887676] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 30.888595] Workqueue: netns cleanup_net [ 30.888947] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 30.889329] 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 d2 aa 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 d2 aa mov $0xffffffffaad2cda0,%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) ... [ 30.890796] RSP: 0018:ffffbd8c40063d70 EFLAGS: 00010286 [ 30.891227] RAX: 0000000000000000 RBX: ffffffffaa9472c0 RCX: 00000000ffffdfff [ 30.891796] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 30.892355] RBP: 0000000000000000 R08: ffffffffab178508 R09: 00000000ffffdfff [ 30.892918] R10: ffffffffab098520 R11: ffffffffab148520 R12: ffff94878233a610 [ 30.893474] R13: ffffbd8c40063e08 R14: ffff94878233ab80 R15: ffffffffac678f90 [ 30.894042] FS: 0000000000000000(0000) GS:ffff9487bed00000(0000) knlGS:0000000000000000 [ 30.894673] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 30.895147] CR2: 00007f74649e3a30 CR3: 000000001e060003 CR4: 0000000000770ef0 [ 30.895715] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 30.896292] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 30.896875] PKRU: 55555554 [ 30.897103] Call Trace: [ 30.897312] <TASK> [ 30.897493] ? __warn (kernel/panic.c:677) [ 30.897767] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 30.898121] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 30.898424] ? handle_bug (arch/x86/kernel/traps.c:238) [ 30.898713] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 30.899042] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 30.899375] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 30.899710] br_dev_delete (net/bridge/br_if.c:396) [ 30.900022] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 30.900384] cleanup_net (net/core/net_namespace.c:630) [ 30.900678] ? process_one_work (kernel/workqueue.c:2606) [ 30.901030] process_one_work (kernel/workqueue.c:2633) [ 30.901348] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 30.901646] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 30.902000] kthread (kernel/kthread.c:388) [ 30.902266] ? __pfx_kthread (kernel/kthread.c:341) [ 30.902574] ret_from_fork (arch/x86/kernel/process.c:147) [ 30.902885] ? __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