syzkaller syzkaller login: [ 9.438236][ T109] udevd (109) used greatest stack depth: 21248 bytes left [ 15.220913][ T28] kauditd_printk_skb: 31 callbacks suppressed [ 15.220929][ T28] audit: type=1400 audit(1782060515.208:59): avc: denied { transition } for pid=226 comm="sshd-session" path="/bin/sh" dev="sda1" ino=90 scontext=system_u:system_r:sshd_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 15.225945][ T28] audit: type=1400 audit(1782060515.208:60): avc: denied { noatsecure } for pid=226 comm="sshd-session" scontext=system_u:system_r:sshd_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 15.229948][ T28] audit: type=1400 audit(1782060515.218:61): avc: denied { write } for pid=226 comm="sh" path="pipe:[13613]" dev="pipefs" ino=13613 scontext=root:sysadm_r:sysadm_t tcontext=system_u:system_r:sshd_t tclass=fifo_file permissive=1 [ 15.233870][ T28] audit: type=1400 audit(1782060515.218:62): avc: denied { rlimitinh } for pid=226 comm="sh" scontext=system_u:system_r:sshd_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 15.237094][ T28] audit: type=1400 audit(1782060515.218:63): avc: denied { siginh } for pid=226 comm="sh" scontext=system_u:system_r:sshd_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 Warning: Permanently added '10.128.1.61' (ED25519) to the list of known hosts. 2026/06/21 16:48:45 parsed 1 programs 2026/06/21 16:48:45 serving rpc on tcp://40339 [ 25.785833][ T28] audit: type=1400 audit(1782060525.778:64): avc: denied { node_bind } for pid=296 comm="syz-execprog" saddr=::1 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:node_t tclass=tcp_socket permissive=1 [ 25.806784][ T28] audit: type=1400 audit(1782060525.778:65): avc: denied { module_request } for pid=296 comm="syz-execprog" kmod="net-pf-2-proto-262-type-1" scontext=root:sysadm_r:sysadm_t tcontext=system_u:system_r:kernel_t tclass=system permissive=1 [ 26.921883][ T28] audit: type=1400 audit(1782060526.908:66): avc: denied { mounton } for pid=302 comm="syz-executor" path="/syzcgroup/unified" dev="sda1" ino=2024 scontext=root:sysadm_r:sysadm_t tcontext=root:object_r:root_t tclass=dir permissive=1 [ 26.925347][ T302] cgroup: Unknown subsys name 'net' [ 26.949899][ T28] audit: type=1400 audit(1782060526.918:67): avc: denied { mount } for pid=302 comm="syz-executor" name="/" dev="cgroup2" ino=1 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:cgroup_t tclass=filesystem permissive=1 [ 26.972100][ T28] audit: type=1400 audit(1782060526.948:68): avc: denied { unmount } for pid=302 comm="syz-executor" scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:cgroup_t tclass=filesystem permissive=1 [ 26.972887][ T302] cgroup: Unknown subsys name 'devices' [ 27.084619][ T302] cgroup: Unknown subsys name 'hugetlb' [ 27.090665][ T302] cgroup: Unknown subsys name 'rlimit' [ 27.233501][ T28] audit: type=1400 audit(1782060527.228:69): avc: denied { setattr } for pid=302 comm="syz-executor" name="raw-gadget" dev="devtmpfs" ino=258 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:device_t tclass=chr_file permissive=1 [ 27.256734][ T28] audit: type=1400 audit(1782060527.228:70): avc: denied { create } for pid=302 comm="syz-executor" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=netlink_generic_socket permissive=1 [ 27.277175][ T28] audit: type=1400 audit(1782060527.228:71): avc: denied { write } for pid=302 comm="syz-executor" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=netlink_generic_socket permissive=1 [ 27.297601][ T28] audit: type=1400 audit(1782060527.228:72): avc: denied { read } for pid=302 comm="syz-executor" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=netlink_generic_socket permissive=1 [ 27.317647][ T306] SELinux: Context root:object_r:swapfile_t is not valid (left unmapped). Setting up swapspace version 1, size = 127995904 bytes [ 27.318654][ T28] audit: type=1400 audit(1782060527.228:73): avc: denied { mounton } for pid=302 comm="syz-executor" path="/proc/sys/fs/binfmt_misc" dev="binfmt_misc" ino=1 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:binfmt_misc_fs_t tclass=dir permissive=1 [ 27.368425][ T302] Adding 124996k swap on ./swap-file. Priority:0 extents:1 across:124996k [ 28.060147][ T308] request_module fs-gadgetfs succeeded, but still no fs? [ 28.463781][ T331] bridge0: port 1(bridge_slave_0) entered blocking state [ 28.470841][ T331] bridge0: port 1(bridge_slave_0) entered disabled state [ 28.478586][ T331] device bridge_slave_0 entered promiscuous mode [ 28.485669][ T331] bridge0: port 2(bridge_slave_1) entered blocking state [ 28.492869][ T331] bridge0: port 2(bridge_slave_1) entered disabled state [ 28.500275][ T331] device bridge_slave_1 entered promiscuous mode [ 28.547200][ T331] bridge0: port 2(bridge_slave_1) entered blocking state [ 28.554298][ T331] bridge0: port 2(bridge_slave_1) entered forwarding state [ 28.561563][ T331] bridge0: port 1(bridge_slave_0) entered blocking state [ 28.568641][ T331] bridge0: port 1(bridge_slave_0) entered forwarding state [ 28.589499][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 28.597180][ T10] bridge0: port 1(bridge_slave_0) entered disabled state [ 28.604935][ T10] bridge0: port 2(bridge_slave_1) entered disabled state [ 28.614115][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 28.622348][ T10] bridge0: port 1(bridge_slave_0) entered blocking state [ 28.629425][ T10] bridge0: port 1(bridge_slave_0) entered forwarding state [ 28.639590][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready [ 28.647934][ T10] bridge0: port 2(bridge_slave_1) entered blocking state [ 28.655003][ T10] bridge0: port 2(bridge_slave_1) entered forwarding state [ 28.667676][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready [ 28.677214][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready [ 28.693928][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_virt_wifi: link becomes ready [ 28.705885][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready [ 28.714214][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): vlan0: link becomes ready [ 28.721618][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready [ 28.730139][ T331] device veth0_vlan entered promiscuous mode [ 28.740780][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready [ 28.751034][ T331] device veth1_macvtap entered promiscuous mode [ 28.760832][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready [ 28.770847][ T10] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready 2026/06/21 16:48:49 executed programs: 0 [ 29.476558][ T371] bridge0: port 1(bridge_slave_0) entered blocking state [ 29.483729][ T371] bridge0: port 1(bridge_slave_0) entered disabled state [ 29.491128][ T371] device bridge_slave_0 entered promiscuous mode [ 29.498309][ T371] bridge0: port 2(bridge_slave_1) entered blocking state [ 29.505487][ T371] bridge0: port 2(bridge_slave_1) entered disabled state [ 29.512944][ T371] device bridge_slave_1 entered promiscuous mode [ 29.559252][ T371] bridge0: port 2(bridge_slave_1) entered blocking state [ 29.566321][ T371] bridge0: port 2(bridge_slave_1) entered forwarding state [ 29.573633][ T371] bridge0: port 1(bridge_slave_0) entered blocking state [ 29.580690][ T371] bridge0: port 1(bridge_slave_0) entered forwarding state [ 29.601064][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 29.608762][ T43] bridge0: port 1(bridge_slave_0) entered disabled state [ 29.616403][ T43] bridge0: port 2(bridge_slave_1) entered disabled state [ 29.632182][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 29.640492][ T43] bridge0: port 1(bridge_slave_0) entered blocking state [ 29.647532][ T43] bridge0: port 1(bridge_slave_0) entered forwarding state [ 29.656490][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready [ 29.664765][ T43] bridge0: port 2(bridge_slave_1) entered blocking state [ 29.671789][ T43] bridge0: port 2(bridge_slave_1) entered forwarding state [ 29.690430][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready [ 29.699848][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready [ 29.715473][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_virt_wifi: link becomes ready [ 29.733388][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready [ 29.741515][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): vlan0: link becomes ready [ 29.749197][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready [ 29.757739][ T371] device veth0_vlan entered promiscuous mode [ 29.768446][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready [ 29.777715][ T371] device veth1_macvtap entered promiscuous mode [ 29.794409][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready [ 29.804496][ T43] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready [ 29.833084][ T375] ================================================================== [ 29.841171][ T375] BUG: KASAN: use-after-free in mutex_lock+0x86/0x1b0 [ 29.847953][ T375] Write of size 8 at addr ffff888112775150 by task syz.2.17/375 [ 29.855579][ T375] [ 29.857911][ T375] CPU: 0 PID: 375 Comm: syz.2.17 Not tainted syzkaller #0 [ 29.865037][ T375] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 [ 29.875104][ T375] Call Trace: [ 29.878382][ T375] [ 29.881315][ T375] __dump_stack+0x21/0x24 [ 29.885704][ T375] dump_stack_lvl+0x110/0x170 [ 29.890382][ T375] ? __cfi_dump_stack_lvl+0x8/0x8 [ 29.895423][ T375] ? mutex_lock+0x86/0x1b0 [ 29.899873][ T375] print_address_description+0x71/0x200 [ 29.905438][ T375] print_report+0x4a/0x60 [ 29.909771][ T375] kasan_report+0x122/0x150 [ 29.914282][ T375] ? mutex_lock+0x86/0x1b0 [ 29.918708][ T375] kasan_check_range+0x249/0x2a0 [ 29.923671][ T375] __kasan_check_write+0x14/0x20 [ 29.928608][ T375] mutex_lock+0x86/0x1b0 [ 29.932855][ T375] ? __cfi_mutex_lock+0x10/0x10 [ 29.937708][ T375] ? kfree+0x6f/0xf0 [ 29.941664][ T375] ? l2tp_session_put+0xaf/0x1a0 [ 29.946605][ T375] ? l2tp_session_delete+0x3df/0x4d0 [ 29.951899][ T375] pppol2tp_release+0x178/0x2b0 [ 29.956751][ T375] sock_close+0xc9/0x220 [ 29.961001][ T375] ? __cfi_sock_close+0x10/0x10 [ 29.965878][ T375] __fput+0x1fd/0x8f0 [ 29.969869][ T375] ____fput+0x15/0x20 [ 29.973851][ T375] task_work_run+0x1e1/0x250 [ 29.978446][ T375] ? __cfi_task_work_run+0x10/0x10 [ 29.983559][ T375] ? __cfi___close_range+0x10/0x10 [ 29.988669][ T375] exit_to_user_mode_loop+0x9b/0xb0 [ 29.993876][ T375] exit_to_user_mode_prepare+0x87/0xd0 [ 29.999366][ T375] syscall_exit_to_user_mode+0x1a/0x30 [ 30.004835][ T375] do_syscall_64+0x58/0xa0 [ 30.009272][ T375] ? clear_bhb_loop+0x30/0x80 [ 30.013949][ T375] ? clear_bhb_loop+0x30/0x80 [ 30.018644][ T375] entry_SYSCALL_64_after_hwframe+0x68/0xd2 [ 30.024540][ T375] RIP: 0033:0x7f592a59ce59 [ 30.028963][ T375] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 [ 30.048568][ T375] RSP: 002b:00007ffdd9f2aae8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 [ 30.057011][ T375] RAX: 0000000000000000 RBX: 00007ffdd9f2abd0 RCX: 00007f592a59ce59 [ 30.064997][ T375] RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 [ 30.072987][ T375] RBP: 0000000000007471 R08: 0000000000000001 R09: 0000000000000000 [ 30.080965][ T375] R10: 0000001b33220000 R11: 0000000000000246 R12: 0000000000000000 [ 30.088950][ T375] R13: 00007f592a815fac R14: 00007f592a815fa8 R15: 00007f592a815fa0 [ 30.096937][ T375] [ 30.099973][ T375] [ 30.102326][ T375] Allocated by task 375: [ 30.106584][ T375] kasan_set_track+0x4b/0x70 [ 30.111195][ T375] kasan_save_alloc_info+0x1f/0x30 [ 30.116322][ T375] __kasan_kmalloc+0x95/0xb0 [ 30.120927][ T375] __kmalloc+0xb4/0x1e0 [ 30.125094][ T375] l2tp_session_create+0x38/0xbd0 [ 30.130130][ T375] pppol2tp_connect+0xbf5/0x1640 [ 30.135079][ T375] __sys_connect+0x3da/0x460 [ 30.139705][ T375] __x64_sys_connect+0x7a/0x90 [ 30.144487][ T375] x64_sys_call+0x88d/0x9a0 [ 30.149005][ T375] do_syscall_64+0x4c/0xa0 [ 30.153437][ T375] entry_SYSCALL_64_after_hwframe+0x68/0xd2 [ 30.159347][ T375] [ 30.161685][ T375] Freed by task 375: [ 30.165584][ T375] kasan_set_track+0x4b/0x70 [ 30.170187][ T375] kasan_save_free_info+0x2b/0x40 [ 30.175222][ T375] ____kasan_slab_free+0x132/0x180 [ 30.180368][ T375] __kasan_slab_free+0x11/0x20 [ 30.185159][ T375] slab_free_freelist_hook+0xc2/0x190 [ 30.190540][ T375] __kmem_cache_free+0xb7/0x1b0 [ 30.195413][ T375] kfree+0x6f/0xf0 [ 30.199146][ T375] l2tp_session_put+0xaf/0x1a0 [ 30.203916][ T375] l2tp_session_delete+0x3df/0x4d0 [ 30.209038][ T375] pppol2tp_release+0x169/0x2b0 [ 30.213911][ T375] sock_close+0xc9/0x220 [ 30.218171][ T375] __fput+0x1fd/0x8f0 [ 30.222164][ T375] ____fput+0x15/0x20 [ 30.226250][ T375] task_work_run+0x1e1/0x250 [ 30.230883][ T375] exit_to_user_mode_loop+0x9b/0xb0 [ 30.236093][ T375] exit_to_user_mode_prepare+0x87/0xd0 [ 30.241567][ T375] syscall_exit_to_user_mode+0x1a/0x30 [ 30.247038][ T375] do_syscall_64+0x58/0xa0 [ 30.251468][ T375] entry_SYSCALL_64_after_hwframe+0x68/0xd2 [ 30.257402][ T375] [ 30.259850][ T375] The buggy address belongs to the object at ffff888112775000 [ 30.259850][ T375] which belongs to the cache kmalloc-512 of size 512 [ 30.273997][ T375] The buggy address is located 336 bytes inside of [ 30.273997][ T375] 512-byte region [ffff888112775000, ffff888112775200) [ 30.287369][ T375] [ 30.289705][ T375] The buggy address belongs to the physical page: [ 30.296137][ T375] page:ffffea000449dd00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112774 [ 30.306405][ T375] head:ffffea000449dd00 order:2 compound_mapcount:0 compound_pincount:0 [ 30.314742][ T375] flags: 0x4000000000010200(slab|head|zone=1) [ 30.320845][ T375] raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100042f00 [ 30.329450][ T375] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 [ 30.338037][ T375] page dumped because: kasan: bad access detected [ 30.344465][ T375] page_owner tracks the page as allocated [ 30.350360][ T375] page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 371, tgid 371 (syz-executor), ts 29818111443, free_ts 28664967617 [ 30.372951][ T375] post_alloc_hook+0x1f5/0x210 [ 30.377739][ T375] prep_new_page+0x1c/0x110 [ 30.382258][ T375] get_page_from_freelist+0x2ca9/0x2d20 [ 30.387820][ T375] __alloc_pages+0x1fa/0x610 [ 30.392434][ T375] alloc_slab_page+0x6e/0xf0 [ 30.397041][ T375] new_slab+0x98/0x3e0 [ 30.401118][ T375] ___slab_alloc+0x70f/0xb70 [ 30.405733][ T375] __slab_alloc+0x5e/0xa0 [ 30.410093][ T375] __kmem_cache_alloc_node+0x204/0x2d0 [ 30.415570][ T375] __kmalloc+0xa4/0x1e0 [ 30.419745][ T375] fib6_info_alloc+0x34/0xe0 [ 30.424438][ T375] ip6_route_info_create+0x51b/0x14d0 [ 30.429830][ T375] ip6_route_add+0x27/0x130 [ 30.434357][ T375] addrconf_add_dev+0x388/0x4a0 [ 30.439222][ T375] addrconf_init_auto_addrs+0x7b9/0xbc0 [ 30.444779][ T375] addrconf_notify+0x7fe/0xe30 [ 30.449559][ T375] page last free stack trace: [ 30.454239][ T375] free_unref_page_prepare+0x80c/0x820 [ 30.459719][ T375] free_unref_page+0x93/0x530 [ 30.464585][ T375] __free_pages+0x67/0x100 [ 30.469014][ T375] __free_slab+0xc7/0x1a0 [ 30.473348][ T375] __unfreeze_partials+0x15a/0x190 [ 30.478476][ T375] put_cpu_partial+0xa9/0x100 [ 30.483172][ T375] __slab_free+0x1c4/0x280 [ 30.487606][ T375] ___cache_free+0xbf/0xd0 [ 30.492040][ T375] qlist_free_all+0xc6/0x140 [ 30.496645][ T375] kasan_quarantine_reduce+0x14a/0x170 [ 30.502117][ T375] __kasan_slab_alloc+0x24/0x80 [ 30.506981][ T375] slab_post_alloc_hook+0x4f/0x2d0 [ 30.512119][ T375] kmem_cache_alloc_node+0x179/0x330 [ 30.517425][ T375] __alloc_skb+0xe8/0x4a0 [ 30.521783][ T375] netlink_ack+0x373/0x1160 [ 30.526297][ T375] netlink_rcv_skb+0x27e/0x450 [ 30.531091][ T375] [ 30.533423][ T375] Memory state around the buggy address: [ 30.539058][ T375] ffff888112775000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.547128][ T375] ffff888112775080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.555199][ T375] >ffff888112775100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.563264][ T375] ^ [ 30.569946][ T375] ffff888112775180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.578016][ T375] ffff888112775200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.586081][ T375] ================================================================== [ 30.602331][ T375] Disabling lock debugging due to kernel taint