[ 16.254987][ T263] ip (263) used greatest stack depth: 23648 bytes left [ 22.523245][ T304] eth1: renamed from tmp [ 23.579178][ T312] eth2: renamed from tmp [ 24.990279][ T323] l2tp_core: L2TP core driver, V2.0 [ 25.005972][ T323] l2tp_netlink: L2TP netlink interface [ 25.134436][ T324] l2tp_ip: L2TP IP encapsulation support (L2TPv3) [ 25.424503][ T329] l2tp_eth: L2TP ethernet pseudowire support (L2TPv3) [ 26.811422][ T339] l2tp_ip6: L2TP IP encapsulation support for IPv6 (L2TPv3) [ 29.268213][ T359] Initializing XFRM netlink socket [ 36.712804][ T36] ================================================================== [ 36.713089][ T36] BUG: KASAN: slab-use-after-free in kobject_put+0xbb/0xd0 [ 36.713357][ T36] Read of size 1 at addr ffff888007ba16c4 by task kworker/u18:0/36 [ 36.713596][ T36] [ 36.713689][ T36] CPU: 1 UID: 0 PID: 36 Comm: kworker/u18:0 Not tainted 6.18.0-rc4-virtme #1 PREEMPT(full) [ 36.713695][ T36] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 36.713699][ T36] Workqueue: l2tp l2tp_session_del_work [l2tp_core] [ 36.713716][ T36] Call Trace: [ 36.713719][ T36] [ 36.713721][ T36] dump_stack_lvl+0x82/0xc0 [ 36.713726][ T36] print_address_description.constprop.0+0x2c/0x3a0 [ 36.713735][ T36] ? kobject_put+0xbb/0xd0 [ 36.713739][ T36] print_report+0xb4/0x270 [ 36.713742][ T36] ? kobject_put+0xbb/0xd0 [ 36.713745][ T36] ? kasan_addr_to_slab+0x21/0x70 [ 36.713749][ T36] ? kobject_put+0xbb/0xd0 [ 36.713752][ T36] kasan_report+0xca/0x100 [ 36.713756][ T36] ? kobject_put+0xbb/0xd0 [ 36.713761][ T36] kobject_put+0xbb/0xd0 [ 36.713765][ T36] netdev_run_todo+0x5f0/0xc60 [ 36.713773][ T36] ? generic_xdp_install+0x410/0x410 [ 36.713776][ T36] ? unregister_netdevice_many+0x20/0x20 [ 36.713783][ T36] l2tp_eth_delete+0x57/0xd0 [l2tp_eth] [ 36.713787][ T36] l2tp_session_del_work+0x29c/0x500 [l2tp_core] [ 36.713795][ T36] ? rcu_is_watching+0x12/0xb0 [ 36.713809][ T36] process_one_work+0xe35/0x1650 [ 36.713819][ T36] ? pwq_dec_nr_in_flight+0x550/0x550 [ 36.713825][ T36] ? assign_work+0x168/0x240 [ 36.713830][ T36] worker_thread+0x591/0xcf0 [ 36.713835][ T36] ? rescuer_thread+0xd10/0xd10 [ 36.713839][ T36] kthread+0x37b/0x5f0 [ 36.713843][ T36] ? kthread_is_per_cpu+0xc0/0xc0 [ 36.713846][ T36] ? ret_from_fork+0x1b/0x270 [ 36.713856][ T36] ? __lock_release+0x5d/0x170 [ 36.713863][ T36] ? rcu_is_watching+0x12/0xb0 [ 36.713866][ T36] ? kthread_is_per_cpu+0xc0/0xc0 [ 36.713870][ T36] ret_from_fork+0x1db/0x270 [ 36.713872][ T36] ? kthread_is_per_cpu+0xc0/0xc0 [ 36.713875][ T36] ret_from_fork_asm+0x11/0x20 [ 36.713892][ T36] [ 36.713893][ T36] [ 36.720019][ T36] Allocated by task 328: [ 36.720141][ T36] kasan_save_stack+0x24/0x40 [ 36.720331][ T36] kasan_save_track+0x14/0x30 [ 36.720495][ T36] __kasan_kmalloc+0x7b/0x90 [ 36.720670][ T36] __kvmalloc_node_noprof+0x2e5/0x8e0 [ 36.720840][ T36] alloc_netdev_mqs+0x7d/0x1370 [ 36.721009][ T36] l2tp_eth_create+0xfa/0x830 [l2tp_eth] [ 36.721169][ T36] l2tp_nl_cmd_session_create+0x6ff/0xe70 [l2tp_netlink] [ 36.721366][ T36] genl_family_rcv_msg_doit+0x1cd/0x2a0 [ 36.721534][ T36] genl_family_rcv_msg+0x337/0x590 [ 36.721701][ T36] genl_rcv_msg+0xa3/0x130 [ 36.721866][ T36] netlink_rcv_skb+0x121/0x340 [ 36.722027][ T36] genl_rcv+0x28/0x40 [ 36.722152][ T36] netlink_unicast+0x4aa/0x780 [ 36.722310][ T36] netlink_sendmsg+0x714/0xbd0 [ 36.722469][ T36] ____sys_sendmsg+0x3dd/0x890 [ 36.722634][ T36] ___sys_sendmsg+0xed/0x170 [ 36.722809][ T36] __sys_sendmsg+0x10b/0x1a0 [ 36.722972][ T36] do_syscall_64+0xc1/0xfd0 [ 36.723145][ T36] entry_SYSCALL_64_after_hwframe+0x4b/0x53 [ 36.723347][ T36] [ 36.723428][ T36] Freed by task 36: [ 36.723575][ T36] kasan_save_stack+0x24/0x40 [ 36.723769][ T36] kasan_save_track+0x14/0x30 [ 36.723931][ T36] __kasan_save_free_info+0x3b/0x60 [ 36.724091][ T36] __kasan_slab_free+0x3f/0x60 [ 36.724253][ T36] kfree+0x21d/0x540 [ 36.724380][ T36] device_release+0x9c/0x210 [ 36.724578][ T36] kobject_cleanup+0xfe/0x360 [ 36.724751][ T36] netdev_run_todo+0x81f/0xc60 [ 36.724917][ T36] l2tp_eth_delete+0x57/0xd0 [l2tp_eth] [ 36.725077][ T36] l2tp_session_del_work+0x29c/0x500 [l2tp_core] [ 36.725280][ T36] process_one_work+0xe35/0x1650 [ 36.725441][ T36] worker_thread+0x591/0xcf0 [ 36.725626][ T36] kthread+0x37b/0x5f0 [ 36.725767][ T36] ret_from_fork+0x1db/0x270 [ 36.725930][ T36] ret_from_fork_asm+0x11/0x20 [ 36.726092][ T36] [ 36.726173][ T36] The buggy address belongs to the object at ffff888007ba1000 [ 36.726173][ T36] which belongs to the cache kmalloc-4k of size 4096 [ 36.726586][ T36] The buggy address is located 1732 bytes inside of [ 36.726586][ T36] freed 4096-byte region [ffff888007ba1000, ffff888007ba2000) [ 36.726999][ T36] [ 36.727083][ T36] The buggy address belongs to the physical page: [ 36.727300][ T36] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ba0 [ 36.727594][ T36] head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 36.727861][ T36] flags: 0x80000000000040(head|node=0|zone=1) [ 36.728080][ T36] page_type: f5(slab) [ 36.728212][ T36] raw: 0080000000000040 ffff888001043700 ffffea0000247610 ffffea0000383410 [ 36.728501][ T36] raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 [ 36.728808][ T36] head: 0080000000000040 ffff888001043700 ffffea0000247610 ffffea0000383410 [ 36.729124][ T36] head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 [ 36.729447][ T36] head: 0080000000000003 ffffea00001ee801 00000000ffffffff 00000000ffffffff [ 36.729776][ T36] head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 36.730085][ T36] page dumped because: kasan: bad access detected [ 36.730283][ T36] [ 36.730364][ T36] Memory state around the buggy address: [ 36.730528][ T36] ffff888007ba1580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 36.730777][ T36] ffff888007ba1600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 36.731008][ T36] >ffff888007ba1680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 36.731244][ T36] ^ [ 36.731441][ T36] ffff888007ba1700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 36.731689][ T36] ffff888007ba1780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 36.731923][ T36] ================================================================== [ 36.732350][ T36] Disabling lock debugging due to kernel taint [ 36.732562][ T36] ------------[ cut here ]------------ [ 36.732787][ T36] refcount_t: underflow; use-after-free. [ 36.733002][ T36] WARNING: CPU: 1 PID: 36 at lib/refcount.c:28 refcount_warn_saturate+0x16f/0x1b0 [ 36.733329][ T36] Modules linked in: xfrm_user l2tp_ip6 l2tp_eth l2tp_ip l2tp_netlink l2tp_core [ 36.733616][ T36] CPU: 1 UID: 0 PID: 36 Comm: kworker/u18:0 Tainted: G B 6.18.0-rc4-virtme #1 PREEMPT(full) [ 36.734273][ T36] Tainted: [B]=BAD_PAGE [ 36.734481][ T36] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 36.734923][ T36] Workqueue: l2tp l2tp_session_del_work [l2tp_core] [ 36.735274][ T36] RIP: 0010:refcount_warn_saturate+0x16f/0x1b0 [ 36.735614][ T36] Code: cc 38 03 80 fb 01 0f 87 29 33 d7 fe 83 e3 01 0f 85 51 ff ff ff c6 05 17 cc 38 03 01 90 48 c7 c7 40 ba 45 95 e8 62 d6 16 ff 90 <0f> 0b 90 90 e9 33 ff ff ff 48 89 df e8 c0 9d a0 ff e9 ba fe ff ff [ 36.736310][ T36] RSP: 0018:ffffc9000028fb20 EFLAGS: 00010286 [ 36.736565][ T36] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 36.736893][ T36] RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000001 [ 36.737163][ T36] RBP: 0000000000000003 R08: 0000000000000000 R09: fffffbfff2c80934 [ 36.737427][ T36] R10: 0000000000000003 R11: ffffc9000028f6c0 R12: 0000000000000001 [ 36.737744][ T36] R13: dffffc0000000000 R14: dead000000000122 R15: dead000000000100 [ 36.737979][ T36] FS: 0000000000000000(0000) GS:ffff8880d5788000(0000) knlGS:0000000000000000 [ 36.738245][ T36] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 36.738441][ T36] CR2: 0000557d84ae60b8 CR3: 0000000066749002 CR4: 0000000000772ef0 [ 36.738751][ T36] PKRU: 55555554 [ 36.738875][ T36] Call Trace: [ 36.738994][ T36] [ 36.739073][ T36] netdev_run_todo+0x5f0/0xc60 [ 36.739235][ T36] ? generic_xdp_install+0x410/0x410 [ 36.739389][ T36] ? unregister_netdevice_many+0x20/0x20 [ 36.739552][ T36] l2tp_eth_delete+0x57/0xd0 [l2tp_eth] [ 36.739789][ T36] l2tp_session_del_work+0x29c/0x500 [l2tp_core] [ 36.739987][ T36] ? rcu_is_watching+0x12/0xb0 [ 36.740145][ T36] process_one_work+0xe35/0x1650 [ 36.740317][ T36] ? pwq_dec_nr_in_flight+0x550/0x550 [ 36.740489][ T36] ? assign_work+0x168/0x240 [ 36.740650][ T36] worker_thread+0x591/0xcf0 [ 36.740875][ T36] ? rescuer_thread+0xd10/0xd10 [ 36.741031][ T36] kthread+0x37b/0x5f0 [ 36.741156][ T36] ? kthread_is_per_cpu+0xc0/0xc0 [ 36.741308][ T36] ? ret_from_fork+0x1b/0x270 [ 36.741462][ T36] ? __lock_release+0x5d/0x170 [ 36.741933][ T36] ? rcu_is_watching+0x12/0xb0 [ 36.742086][ T36] ? kthread_is_per_cpu+0xc0/0xc0 [ 36.742241][ T36] ret_from_fork+0x1db/0x270 [ 36.742393][ T36] ? kthread_is_per_cpu+0xc0/0xc0 [ 36.742547][ T36] ret_from_fork_asm+0x11/0x20 [ 36.742792][ T36] [ 36.743019][ T36] irq event stamp: 120271 [ 36.743229][ T36] hardirqs last enabled at (120271): [] finish_task_switch.isra.0+0x245/0x960 [ 36.743665][ T36] hardirqs last disabled at (120270): [] __schedule+0x94a/0x1b10 [ 36.744026][ T36] softirqs last enabled at (119570): [] handle_softirqs+0x352/0x610 [ 36.744297][ T36] softirqs last disabled at (119427): [] irq_exit_rcu+0xab/0x100 [ 36.744592][ T36] ---[ end trace 0000000000000000 ]---