[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [ 8.710989][ T22] audit: type=1400 audit(1583678990.941:10): avc: denied { watch } for pid=1801 comm="restorecond" path="/root/.ssh" dev="sda1" ino=16179 scontext=system_u:system_r:kernel_t:s0 tcontext=unconfined_u:object_r:ssh_home_t:s0 tclass=dir permissive=1 [ 8.716032][ T22] audit: type=1400 audit(1583678990.941:11): avc: denied { watch } for pid=1801 comm="restorecond" path="/etc/selinux/restorecond.conf" dev="sda1" ino=2280 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 12.362417][ T22] audit: type=1400 audit(1583678994.591:12): avc: denied { map } for pid=1866 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.1.38' (ECDSA) to the list of known hosts. [ 18.369342][ T22] audit: type=1400 audit(1583679000.591:13): avc: denied { map } for pid=1878 comm="syz-executor613" path="/root/syz-executor613838331" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 18.377978][ T1885] cgroup1: Unknown subsys name 'perf_event' [ 18.378994][ T1889] cgroup1: Unknown subsys name 'perf_event' [ 18.379867][ T1885] cgroup1: Unknown subsys name 'net_cls' [ 18.382316][ T1890] cgroup1: Unknown subsys name 'perf_event' [ 18.383338][ T1886] cgroup1: Unknown subsys name 'perf_event' [ 18.384136][ T1890] cgroup1: Unknown subsys name 'net_cls' [ 18.385505][ T1886] cgroup1: Unknown subsys name 'net_cls' [ 18.391729][ T1889] cgroup1: Unknown subsys name 'net_cls' [ 18.391774][ T1887] cgroup1: Unknown subsys name 'perf_event' [ 18.404206][ T1888] cgroup1: Unknown subsys name 'perf_event' [ 18.410344][ T1888] cgroup1: Unknown subsys name 'net_cls' executing program executing program executing program executing program executing program executing program [ 18.416549][ T1887] cgroup1: Unknown subsys name 'net_cls' [ 18.420240][ T22] audit: type=1400 audit(1583679000.641:14): avc: denied { associate } for pid=1890 comm="syz-executor613" name="syz0" scontext=unconfined_u:object_r:unlabeled_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=filesystem permissive=1 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 20.360990][ T1996] ================================================================== [ 20.369105][ T1996] BUG: KASAN: use-after-free in free_netdev+0x186/0x300 [ 20.376021][ T1996] Read of size 8 at addr ffff8881cf6534f0 by task syz-executor613/1996 [ 20.384325][ T1996] [ 20.386631][ T1996] CPU: 1 PID: 1996 Comm: syz-executor613 Not tainted 5.4.24-syzkaller-00181-g3334f0da669e #0 [ 20.397015][ T1996] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 20.407045][ T1996] Call Trace: [ 20.410311][ T1996] dump_stack+0x1b0/0x228 [ 20.414619][ T1996] ? show_regs_print_info+0x18/0x18 [ 20.419792][ T1996] ? vprintk_func+0x105/0x110 [ 20.424441][ T1996] ? printk+0xc0/0x109 [ 20.428484][ T1996] print_address_description+0x96/0x5d0 [ 20.434001][ T1996] ? devkmsg_release+0x127/0x127 [ 20.438914][ T1996] ? call_rcu+0x10/0x10 [ 20.443050][ T1996] __kasan_report+0x14b/0x1c0 [ 20.447711][ T1996] ? free_netdev+0x186/0x300 [ 20.452284][ T1996] kasan_report+0x26/0x50 [ 20.456607][ T1996] __asan_report_load8_noabort+0x14/0x20 [ 20.462337][ T1996] free_netdev+0x186/0x300 [ 20.466740][ T1996] netdev_run_todo+0xbc4/0xe00 [ 20.471491][ T1996] ? netdev_refcnt_read+0x1c0/0x1c0 [ 20.476677][ T1996] ? mutex_trylock+0xb0/0xb0 [ 20.481244][ T1996] ? netlink_net_capable+0x124/0x160 [ 20.486501][ T1996] rtnetlink_rcv_msg+0x963/0xc20 [ 20.491585][ T1996] ? is_bpf_text_address+0x2c8/0x2e0 [ 20.496841][ T1996] ? __kernel_text_address+0x9a/0x110 [ 20.502807][ T1996] ? rtnetlink_bind+0x80/0x80 [ 20.507461][ T1996] ? arch_stack_walk+0x98/0xe0 [ 20.512212][ T1996] ? __rcu_read_lock+0x50/0x50 [ 20.516950][ T1996] ? avc_has_perm_noaudit+0x2fc/0x3f0 [ 20.522302][ T1996] ? rhashtable_jhash2+0x1f1/0x330 [ 20.527401][ T1996] ? jhash+0x750/0x750 [ 20.531446][ T1996] ? rht_key_hashfn+0x157/0x240 [ 20.536285][ T1996] ? deferred_put_nlk_sk+0x200/0x200 [ 20.541558][ T1996] ? __alloc_skb+0x109/0x540 [ 20.546132][ T1996] ? jhash+0x750/0x750 [ 20.550173][ T1996] ? netlink_hash+0xd0/0xd0 [ 20.554815][ T1996] ? avc_has_perm+0x15f/0x260 [ 20.559475][ T1996] ? __rcu_read_lock+0x50/0x50 [ 20.564874][ T1996] netlink_rcv_skb+0x1f0/0x460 [ 20.570002][ T1996] ? rtnetlink_bind+0x80/0x80 [ 20.574857][ T1996] ? netlink_ack+0xa80/0xa80 [ 20.579534][ T1996] ? netlink_autobind+0x1c0/0x1c0 [ 20.584984][ T1996] ? __rcu_read_lock+0x50/0x50 [ 20.589741][ T1996] ? selinux_vm_enough_memory+0x160/0x160 [ 20.595608][ T1996] rtnetlink_rcv+0x1c/0x20 [ 20.600106][ T1996] netlink_unicast+0x87c/0xa20 [ 20.605129][ T1996] ? netlink_detachskb+0x60/0x60 [ 20.610051][ T1996] ? security_netlink_send+0xab/0xc0 [ 20.615331][ T1996] netlink_sendmsg+0x9a7/0xd40 [ 20.620075][ T1996] ? netlink_getsockopt+0x900/0x900 [ 20.625254][ T1996] ? security_socket_sendmsg+0xad/0xc0 [ 20.630685][ T1996] ? netlink_getsockopt+0x900/0x900 [ 20.635944][ T1996] ____sys_sendmsg+0x56f/0x860 [ 20.640683][ T1996] ? __sys_sendmsg_sock+0x2a0/0x2a0 [ 20.645854][ T1996] ? __fdget+0x17c/0x200 [ 20.650867][ T1996] __sys_sendmsg+0x26a/0x350 [ 20.655429][ T1996] ? errseq_set+0x102/0x140 [ 20.659911][ T1996] ? ____sys_sendmsg+0x860/0x860 [ 20.664831][ T1996] ? __rcu_read_lock+0x50/0x50 [ 20.669566][ T1996] ? alloc_file_pseudo+0x282/0x310 [ 20.674659][ T1996] ? __kasan_check_write+0x14/0x20 [ 20.679751][ T1996] ? __kasan_check_write+0x14/0x20 [ 20.684918][ T1996] ? __fpregs_load_activate+0x2fc/0x3b0 [ 20.690435][ T1996] ? switch_fpu_return+0x10/0x10 [ 20.695807][ T1996] ? __kasan_check_read+0x11/0x20 [ 20.700803][ T1996] ? fput_many+0x47/0x1a0 [ 20.705376][ T1996] __x64_sys_sendmsg+0x7f/0x90 [ 20.710112][ T1996] do_syscall_64+0xc0/0x100 [ 20.714598][ T1996] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 20.720461][ T1996] RIP: 0033:0x447509 [ 20.724329][ T1996] Code: e8 3c e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 ab 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 20.745044][ T1996] RSP: 002b:00007f241eb05d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 20.753434][ T1996] RAX: ffffffffffffffda RBX: 00000000006ddc68 RCX: 0000000000447509 [ 20.761382][ T1996] RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005 [ 20.769335][ T1996] RBP: 00000000006ddc60 R08: 0000000000000000 R09: 0000000000000000 [ 20.777290][ T1996] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc6c [ 20.785276][ T1996] R13: 0000003065736f72 R14: 0000000000000000 R15: 0000000000000000 [ 20.793231][ T1996] [ 20.795539][ T1996] Allocated by task 1996: [ 20.799847][ T1996] __kasan_kmalloc+0x117/0x1b0 [ 20.804594][ T1996] kasan_kmalloc+0x9/0x10 [ 20.808907][ T1996] __kmalloc+0x102/0x310 [ 20.813129][ T1996] sk_prot_alloc+0x11c/0x2f0 [ 20.817700][ T1996] sk_alloc+0x35/0x300 [ 20.821739][ T1996] tun_chr_open+0x7b/0x4a0 [ 20.826156][ T1996] misc_open+0x3ea/0x440 [ 20.830372][ T1996] chrdev_open+0x60a/0x670 [ 20.834758][ T1996] do_dentry_open+0x8f7/0x1070 [ 20.839491][ T1996] vfs_open+0x73/0x80 [ 20.843443][ T1996] path_openat+0x1681/0x42d0 [ 20.848872][ T1996] do_filp_open+0x1f7/0x430 [ 20.853362][ T1996] do_sys_open+0x36f/0x7a0 [ 20.857757][ T1996] __x64_sys_openat+0xa2/0xb0 [ 20.862411][ T1996] do_syscall_64+0xc0/0x100 [ 20.866889][ T1996] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 20.872836][ T1996] [ 20.875144][ T1996] Freed by task 1994: [ 20.879110][ T1996] __kasan_slab_free+0x168/0x220 [ 20.884016][ T1996] kasan_slab_free+0xe/0x10 [ 20.888490][ T1996] kfree+0x170/0x6d0 [ 20.892369][ T1996] __sk_destruct+0x45f/0x4e0 [ 20.896933][ T1996] __sk_free+0x35d/0x430 [ 20.901158][ T1996] sk_free+0x45/0x50 [ 20.905022][ T1996] __tun_detach+0x15d0/0x1a40 [ 20.909699][ T1996] tun_chr_close+0xb8/0xd0 [ 20.914096][ T1996] __fput+0x295/0x710 [ 20.918054][ T1996] ____fput+0x15/0x20 [ 20.922010][ T1996] task_work_run+0x176/0x1a0 [ 20.926576][ T1996] prepare_exit_to_usermode+0x2d8/0x370 [ 20.932094][ T1996] syscall_return_slowpath+0x6f/0x500 [ 20.937435][ T1996] do_syscall_64+0xe8/0x100 [ 20.941923][ T1996] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 20.947784][ T1996] [ 20.950088][ T1996] The buggy address belongs to the object at ffff8881cf653000 [ 20.950088][ T1996] which belongs to the cache kmalloc-2k of size 2048 [ 20.964123][ T1996] The buggy address is located 1264 bytes inside of [ 20.964123][ T1996] 2048-byte region [ffff8881cf653000, ffff8881cf653800) [ 20.977556][ T1996] The buggy address belongs to the page: [ 20.983165][ T1996] page:ffffea00073d9400 refcount:1 mapcount:0 mapping:ffff8881da802800 index:0x0 compound_mapcount: 0 [ 20.994068][ T1996] flags: 0x8000000000010200(slab|head) [ 20.999762][ T1996] raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881da802800 [ 21.008338][ T1996] raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 [ 21.016903][ T1996] page dumped because: kasan: bad access detected [ 21.023303][ T1996] [ 21.025607][ T1996] Memory state around the buggy address: [ 21.031358][ T1996] ffff8881cf653380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.039612][ T1996] ffff8881cf653400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.047650][ T1996] >ffff8881cf653480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.055683][ T1996] ^ executing program executing program executing program [ 21.063368][ T1996] ffff8881cf653500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.071400][ T1996] ffff8881cf653580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 21.079557][ T1996] ================================================================== [ 21.087744][ T1996] Disabling lock debugging due to kernel taint executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing 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executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing 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