====================================== | [ 174.152220] ------------[ cut here ]------------ | [ 174.152494] refcount_t: underflow; use-after-free. | [ 174.152759] WARNING: CPU: 1 PID: 68 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) | [ 174.153194] Modules linked in: xfrm_user psample macsec fou ip6_gre ip_gre gre sch_htb vxlan ip6_udp_tunnel udp_tunnel nft_chain_nat xt_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_compat nf_tables libcrc32c act_mirred cls_u32 sch_ingress ifb poly1305_generic libpoly1305 chacha_generic libchacha chacha20poly1305 tls [last unloaded: netdevsim] [ 174.155156] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 174.155732] Workqueue: netns cleanup_net [ 174.155946] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 174.156214] 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 e8 37 33 93 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 e8 37 33 93 mov $0xffffffff933337e8,%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 [ 174.157163] RSP: 0018:ffffc114c0263d78 EFLAGS: 00010286 [ 174.157433] RAX: 0000000000000000 RBX: ffff9e61c29ee000 RCX: 00000000ffffdfff [ 174.157817] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 174.158178] RBP: ffff9e61c29ee610 R08: ffffffff93778508 R09: 00000000ffffdfff [ 174.158538] R10: ffffffff93698520 R11: ffffffff93748520 R12: ffff9e61c29ee000 [ 174.158904] R13: ffffc114c0263e08 R14: ffff9e61c29eeb80 R15: ffffffff94c78f90 [ 174.159266] FS: 0000000000000000(0000) GS:ffff9e61fec80000(0000) knlGS:0000000000000000 [ 174.159674] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 174.159971] CR2: 000055b4c6308dec CR3: 00000000049b4003 CR4: 0000000000770ef0 [ 174.160331] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 174.160692] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 174.161063] PKRU: 55555554 [ 174.161207] Call Trace: [ 174.161342] <TASK> [ 174.161458] ? __warn (kernel/panic.c:677) [ 174.161633] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 174.161880] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 174.162075] ? handle_bug (arch/x86/kernel/traps.c:238) [ 174.162262] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 174.162461] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 174.162685] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 174.162930] ? refcount_warn_saturate (lib/refcount.c:28 (discriminator 3)) [ 174.163169] br_sysfs_delbr (net/bridge/br_sysfs_br.c:1086) [ 174.163363] br_dev_delete (net/bridge/br_if.c:396) [ 174.163554] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 174.163783] cleanup_net (net/core/net_namespace.c:630) [ 174.163979] ? process_one_work (kernel/workqueue.c:2606) [ 174.164199] process_one_work (kernel/workqueue.c:2633) [ 174.164411] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 174.164608] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 174.164840] kthread (kernel/kthread.c:388) [ 174.165009] ? __pfx_kthread (kernel/kthread.c:341) [ 174.165207] ret_from_fork (arch/x86/kernel/process.c:147) [ 174.165398] ? __pfx_kthread (kernel/kthread.c:341) [ 174.165594] ret_from_fork_asm (arch/x86/entry/entry_64.S:250) | [ 174.168137] ------------[ cut here ]------------ | [ 174.168380] sysfs group 'bridge' not found for kobject 'test-br0' | [ 174.168707] WARNING: CPU: 1 PID: 68 at fs/sysfs/group.c:282 sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) | [ 174.169128] Modules linked in: xfrm_user psample macsec fou ip6_gre ip_gre gre sch_htb vxlan ip6_udp_tunnel udp_tunnel nft_chain_nat xt_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_compat nf_tables libcrc32c act_mirred cls_u32 sch_ingress ifb poly1305_generic libpoly1305 chacha_generic libchacha chacha20poly1305 tls [last unloaded: netdevsim] [ 174.171144] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 174.171731] Workqueue: netns cleanup_net [ 174.171943] RIP: 0010:sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 174.172192] 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 d0 cd 32 93 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 d0 cd 32 93 mov $0xffffffff9332cdd0,%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) ... [ 174.173121] RSP: 0018:ffffc114c0263d70 EFLAGS: 00010286 [ 174.173391] RAX: 0000000000000000 RBX: ffffffff92f472c0 RCX: 00000000ffffdfff [ 174.173750] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001 [ 174.174116] RBP: 0000000000000000 R08: ffffffff93778508 R09: 00000000ffffdfff [ 174.174476] R10: ffffffff93698520 R11: ffffffff93748520 R12: ffff9e61c29ee610 [ 174.174843] R13: ffffc114c0263e08 R14: ffff9e61c29eeb80 R15: ffffffff94c78f90 [ 174.175204] FS: 0000000000000000(0000) GS:ffff9e61fec80000(0000) knlGS:0000000000000000 [ 174.175610] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 174.175910] CR2: 000055b4c6308dec CR3: 00000000049b4003 CR4: 0000000000770ef0 [ 174.176273] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 174.176637] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 174.177014] PKRU: 55555554 [ 174.177159] Call Trace: [ 174.177292] <TASK> [ 174.177409] ? __warn (kernel/panic.c:677) [ 174.177582] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 174.177807] ? report_bug (lib/bug.c:201 lib/bug.c:219) [ 174.178002] ? handle_bug (arch/x86/kernel/traps.c:238) [ 174.178188] ? exc_invalid_op (arch/x86/kernel/traps.c:259 (discriminator 1)) [ 174.178388] ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:568) [ 174.178612] ? sysfs_remove_group (fs/sysfs/group.c:282 (discriminator 1)) [ 174.178835] br_dev_delete (net/bridge/br_if.c:396) [ 174.179026] br_net_exit_batch_rtnl (net/bridge/br.c:369) [ 174.179257] cleanup_net (net/core/net_namespace.c:630) [ 174.179449] ? process_one_work (kernel/workqueue.c:2606) [ 174.179665] process_one_work (kernel/workqueue.c:2633) [ 174.179884] worker_thread (kernel/workqueue.c:2700 kernel/workqueue.c:2787) [ 174.180083] ? __pfx_worker_thread (kernel/workqueue.c:2733) [ 174.180307] kthread (kernel/kthread.c:388) [ 174.180474] ? __pfx_kthread (kernel/kthread.c:341) [ 174.180669] ret_from_fork (arch/x86/kernel/process.c:147) [ 174.180866] ? __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