====================================== | [ 94.435224] ------------[ cut here ]------------ | [ 94.435497] refcount_t: underflow; use-after-free. | [ 94.435773] WARNING: CPU: 3 PID: 11 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 94.436225] Modules linked in: xt_HL nft_compat nf_tables libcrc32c amt udp_tunnel sch_etf sch_fq act_mirred cls_flower sch_ingress ip6_gre gre [ 94.437296] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 94.437903] Workqueue: netns cleanup_net [ 94.438130] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 94.438427] 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 53 b7 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 53 b7 mov $0xffffffffb75337b8,%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 [ 94.439450] RSP: 0018:ffffa7d240063d78 EFLAGS: 00010286 [ 94.439732] RAX: 0000000000000000 RBX: ffff899e835fe000 RCX: 00000000ffffdfff [ 94.440133] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 94.440518] RBP: ffff899e835fe610 R08: ffffffffb7978508 R09: 00000000ffffdfff [ 94.440925] R10: ffffffffb7898520 R11: ffffffffb7948520 R12: ffff899e835fe000 [ 94.441328] R13: ffffa7d240063e08 R14: ffff899e835feb80 R15: ffff899e829a5c50 [ 94.441729] FS: 0000000000000000(0000) GS:ffff899ebed80000(0000) knlGS:0000000000000000 [ 94.442178] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 94.442504] CR2: 00007f77335160e0 CR3: 000000001f460003 CR4: 0000000000770ef0 [ 94.442882] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 94.443250] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 94.443634] PKRU: 55555554 [ 94.443784] Call Trace: [ 94.443931] <TASK> [ 94.444090] ? __warn (kernel/panic.c:677) [ 94.444269] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 94.444514] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 94.444720] ? handle_bug (arch/x86/kernel/traps.c:238) [ 94.444933] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 94.445160] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 94.445394] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 94.445687] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 94.445941] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) [ 94.446147] br_dev_delete (net/bridge/br_if.c:396) [ 94.446350] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 94.446633] cleanup_net (net/core/net_namespace.c:630) [ 94.446837] ? process_one_work (kernel/workqueue.c:2606) xx__-> [ 94.447060] process_one_work (kernel/workqueue.c:2633) [ 94.447322] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 94.447540] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 94.447770] kthread (kernel/kthread.c:388) [ 94.447964] ? __pfx_kthread (kernel/kthread.c:341) [ 94.448183] ret_from_fork (arch/x86/kernel/process.c:147) [ 94.448423] ? __pfx_kthread (kernel/kthread.c:341) [ 94.448639] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) | [ 94.451328] ------------[ cut here ]------------ | [ 94.451572] sysfs group 'bridge' not found for kobject 'br0' | [ 94.451894] WARNING: CPU: 3 PID: 11 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) | [ 94.452317] Modules linked in: xt_HL nft_compat nf_tables libcrc32c amt udp_tunnel sch_etf sch_fq act_mirred cls_flower sch_ingress ip6_gre gre [ 94.453442] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 94.454033] Workqueue: netns cleanup_net [ 94.454244] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 94.454499] 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 52 b7 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 52 b7 mov $0xffffffffb752cda0,%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) ... [ 94.455457] RSP: 0018:ffffa7d240063d70 EFLAGS: 00010286 [ 94.455732] RAX: 0000000000000000 RBX: ffffffffb71472c0 RCX: 00000000ffffdfff [ 94.456109] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 94.456475] RBP: 0000000000000000 R08: ffffffffb7978508 R09: 00000000ffffdfff [ 94.456848] R10: ffffffffb7898520 R11: ffffffffb7948520 R12: ffff899e835fe610 [ 94.457218] R13: ffffa7d240063e08 R14: ffff899e835feb80 R15: ffff899e829a5c50 [ 94.457587] FS: 0000000000000000(0000) GS:ffff899ebed80000(0000) knlGS:0000000000000000 [ 94.458009] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 94.458310] CR2: 00007f77335160e0 CR3: 000000001f460003 CR4: 0000000000770ef0 [ 94.458689] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 94.459066] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 94.459455] PKRU: 55555554 [ 94.459602] Call Trace: [ 94.459752] <TASK> [ 94.459880] ? __warn (kernel/panic.c:677) [ 94.460091] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 94.460313] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 94.460512] ? handle_bug (arch/x86/kernel/traps.c:238) [ 94.460702] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 94.460928] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 94.461166] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 94.461402] br_dev_delete (net/bridge/br_if.c:396) [ 94.461598] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 94.461859] cleanup_net (net/core/net_namespace.c:630) [ 94.462077] ? process_one_work (kernel/workqueue.c:2606) [ 94.462313] process_one_work (kernel/workqueue.c:2633) [ 94.462532] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 94.462741] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 94.463002] kthread (kernel/kthread.c:388) [ 94.463213] ? __pfx_kthread (kernel/kthread.c:341) [ 94.463415] ret_from_fork (arch/x86/kernel/process.c:147) [ 94.463622] ? __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