[[0;32m OK [0m] Reached target Login Prompts.
[[0;32m OK [0m] Reached target Multi-User System.
[[0;32m OK [0m] Reached target Graphical Interface.
Starting Update UTMP about System Runlevel Changes...
[[0;32m OK [0m] Started Update UTMP about System Runlevel Changes.
Debian GNU/Linux 9 syzkaller ttyS0
Warning: Permanently added '10.128.1.140' (ECDSA) to the list of known hosts.
2021/11/29 08:03:02 fuzzer started
2021/11/29 08:03:02 connecting to host at 10.128.0.169:35737
2021/11/29 08:03:02 checking machine...
2021/11/29 08:03:02 checking revisions...
2021/11/29 08:03:02 testing simple program...
syzkaller login: [ 76.260301][ T6535] cgroup: Unknown subsys name 'net'
[ 76.266763][ T6535]
[ 76.269106][ T6535] =========================
[ 76.273697][ T6535] WARNING: held lock freed!
[ 76.278203][ T6535] 5.16.0-rc2-next-20211129-syzkaller #0 Not tainted
[ 76.284915][ T6535] -------------------------
[ 76.289419][ T6535] syz-executor/6535 is freeing memory ffff8881472c5400-ffff8881472c55ff, with a lock still held there!
[ 76.300533][ T6535] ffff8881472c5548 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_destroy_root+0x81/0xb0
[ 76.310470][ T6535] 2 locks held by syz-executor/6535:
[ 76.315733][ T6535] #0: ffffffff8bbc5d08 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock_and_drain_offline+0xa5/0x900
[ 76.326387][ T6535] #1: ffff8881472c5548 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_destroy_root+0x81/0xb0
[ 76.336653][ T6535]
[ 76.336653][ T6535] stack backtrace:
[ 76.342616][ T6535] CPU: 0 PID: 6535 Comm: syz-executor Not tainted 5.16.0-rc2-next-20211129-syzkaller #0
[ 76.352318][ T6535] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 76.362381][ T6535] Call Trace:
[ 76.365653][ T6535]
[ 76.368592][ T6535] dump_stack_lvl+0xcd/0x134
[ 76.373550][ T6535] debug_check_no_locks_freed.cold+0x9d/0xa9
[ 76.379581][ T6535] ? lockdep_hardirqs_on+0x79/0x100
[ 76.384818][ T6535] slab_free_freelist_hook+0x73/0x1c0
[ 76.390208][ T6535] ? kernfs_put.part.0+0x331/0x540
[ 76.395327][ T6535] kfree+0xe0/0x430
[ 76.399142][ T6535] ? kmem_cache_free+0xba/0x4a0
[ 76.404036][ T6535] ? rwlock_bug.part.0+0x90/0x90
[ 76.409085][ T6535] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70
[ 76.415338][ T6535] kernfs_put.part.0+0x331/0x540
[ 76.420292][ T6535] kernfs_put+0x42/0x50
[ 76.424553][ T6535] __kernfs_remove+0x7a3/0xb20
[ 76.429329][ T6535] ? kernfs_next_descendant_post+0x2f0/0x2f0
[ 76.435310][ T6535] ? down_write+0xde/0x150
[ 76.439753][ T6535] ? down_write_killable_nested+0x180/0x180
[ 76.445658][ T6535] kernfs_destroy_root+0x89/0xb0
[ 76.450894][ T6535] cgroup_setup_root+0x3a6/0xad0
[ 76.455869][ T6535] ? rebind_subsystems+0x10e0/0x10e0
[ 76.461164][ T6535] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80
[ 76.467431][ T6535] cgroup1_get_tree+0xd33/0x1390
[ 76.472376][ T6535] vfs_get_tree+0x89/0x2f0
[ 76.476792][ T6535] path_mount+0x1320/0x1fa0
[ 76.481302][ T6535] ? kmem_cache_free+0xba/0x4a0
[ 76.486157][ T6535] ? finish_automount+0xaf0/0xaf0
[ 76.491193][ T6535] ? putname+0xfe/0x140
[ 76.495353][ T6535] __x64_sys_mount+0x27f/0x300
[ 76.500120][ T6535] ? copy_mnt_ns+0xae0/0xae0
[ 76.504971][ T6535] ? syscall_enter_from_user_mode+0x21/0x70
[ 76.510899][ T6535] do_syscall_64+0x35/0xb0
[ 76.515408][ T6535] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 76.521306][ T6535] RIP: 0033:0x7fd22140301a
[ 76.525723][ T6535] Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
[ 76.545507][ T6535] RSP: 002b:00007ffc25f03ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
[ 76.553918][ T6535] RAX: ffffffffffffffda RBX: 00007ffc25f04038 RCX: 00007fd22140301a
[ 76.561884][ T6535] RDX: 00007fd221465fd6 RSI: 00007fd22145c29a RDI: 00007fd22145ad71
[ 76.570111][ T6535] RBP: 00007fd22145c29a R08: 00007fd22145c3f7 R09: 0000000000000026
[ 76.578074][ T6535] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc25f03eb0
[ 76.586052][ T6535] R13: 00007ffc25f04058 R14: 00007ffc25f03f80 R15: 00007fd22145c3f1
[ 76.594045][ T6535]
[ 76.597398][ T6535] ==================================================================
[ 76.605471][ T6535] BUG: KASAN: use-after-free in up_write+0x3ac/0x470
[ 76.612166][ T6535] Read of size 8 at addr ffff8881472c5540 by task syz-executor/6535
[ 76.620147][ T6535]
[ 76.622467][ T6535] CPU: 1 PID: 6535 Comm: syz-executor Not tainted 5.16.0-rc2-next-20211129-syzkaller #0
[ 76.632179][ T6535] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 76.642226][ T6535] Call Trace:
[ 76.645504][ T6535]
[ 76.648428][ T6535] dump_stack_lvl+0xcd/0x134
[ 76.653022][ T6535] print_address_description.constprop.0.cold+0xa5/0x3ed
[ 76.660048][ T6535] ? up_write+0x3ac/0x470
[ 76.664375][ T6535] ? up_write+0x3ac/0x470
[ 76.668801][ T6535] kasan_report.cold+0x83/0xdf
[ 76.673581][ T6535] ? up_write+0x3ac/0x470
[ 76.677929][ T6535] up_write+0x3ac/0x470
[ 76.682087][ T6535] cgroup_setup_root+0x3a6/0xad0
[ 76.687043][ T6535] ? rebind_subsystems+0x10e0/0x10e0
[ 76.692791][ T6535] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80
[ 76.699040][ T6535] cgroup1_get_tree+0xd33/0x1390
[ 76.704181][ T6535] vfs_get_tree+0x89/0x2f0
[ 76.708693][ T6535] path_mount+0x1320/0x1fa0
[ 76.713283][ T6535] ? kmem_cache_free+0xba/0x4a0
[ 76.718143][ T6535] ? finish_automount+0xaf0/0xaf0
[ 76.723172][ T6535] ? putname+0xfe/0x140
[ 76.727448][ T6535] __x64_sys_mount+0x27f/0x300
[ 76.732214][ T6535] ? copy_mnt_ns+0xae0/0xae0
[ 76.736804][ T6535] ? syscall_enter_from_user_mode+0x21/0x70
[ 76.742699][ T6535] do_syscall_64+0x35/0xb0
[ 76.747138][ T6535] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 76.753035][ T6535] RIP: 0033:0x7fd22140301a
[ 76.757453][ T6535] Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
[ 76.777234][ T6535] RSP: 002b:00007ffc25f03ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
[ 76.785649][ T6535] RAX: ffffffffffffffda RBX: 00007ffc25f04038 RCX: 00007fd22140301a
[ 76.793815][ T6535] RDX: 00007fd221465fd6 RSI: 00007fd22145c29a RDI: 00007fd22145ad71
[ 76.801949][ T6535] RBP: 00007fd22145c29a R08: 00007fd22145c3f7 R09: 0000000000000026
[ 76.809915][ T6535] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc25f03eb0
[ 76.817985][ T6535] R13: 00007ffc25f04058 R14: 00007ffc25f03f80 R15: 00007fd22145c3f1
[ 76.825963][ T6535]
[ 76.829059][ T6535]
[ 76.831384][ T6535] Allocated by task 6535:
[ 76.835698][ T6535] kasan_save_stack+0x1e/0x50
[ 76.840467][ T6535] __kasan_kmalloc+0xa9/0xd0
[ 76.845163][ T6535] kernfs_create_root+0x4c/0x410
[ 76.850270][ T6535] cgroup_setup_root+0x243/0xad0
[ 76.855557][ T6535] cgroup1_get_tree+0xd33/0x1390
[ 76.860668][ T6535] vfs_get_tree+0x89/0x2f0
[ 76.865124][ T6535] path_mount+0x1320/0x1fa0
[ 76.869643][ T6535] __x64_sys_mount+0x27f/0x300
[ 76.874519][ T6535] do_syscall_64+0x35/0xb0
[ 76.878937][ T6535] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 76.884830][ T6535]
[ 76.887158][ T6535] Freed by task 6535:
[ 76.891141][ T6535] kasan_save_stack+0x1e/0x50
[ 76.895844][ T6535] kasan_set_track+0x21/0x30
[ 76.900471][ T6535] kasan_set_free_info+0x20/0x30
[ 76.905444][ T6535] __kasan_slab_free+0x103/0x170
[ 76.910485][ T6535] slab_free_freelist_hook+0x8b/0x1c0
[ 76.915868][ T6535] kfree+0xe0/0x430
[ 76.919780][ T6535] kernfs_put.part.0+0x331/0x540
[ 76.924733][ T6535] kernfs_put+0x42/0x50
[ 76.928907][ T6535] __kernfs_remove+0x7a3/0xb20
[ 76.933694][ T6535] kernfs_destroy_root+0x89/0xb0
[ 76.938645][ T6535] cgroup_setup_root+0x3a6/0xad0
[ 76.943768][ T6535] cgroup1_get_tree+0xd33/0x1390
[ 76.948723][ T6535] vfs_get_tree+0x89/0x2f0
[ 76.953239][ T6535] path_mount+0x1320/0x1fa0
[ 76.957743][ T6535] __x64_sys_mount+0x27f/0x300
[ 76.962502][ T6535] do_syscall_64+0x35/0xb0
[ 76.966916][ T6535] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 76.972806][ T6535]
[ 76.975117][ T6535] The buggy address belongs to the object at ffff8881472c5400
[ 76.975117][ T6535] which belongs to the cache kmalloc-512 of size 512
[ 76.989173][ T6535] The buggy address is located 320 bytes inside of
[ 76.989173][ T6535] 512-byte region [ffff8881472c5400, ffff8881472c5600)
[ 77.002439][ T6535] The buggy address belongs to the page:
[ 77.008145][ T6535] page:ffffea00051cb100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1472c4
[ 77.018488][ T6535] head:ffffea00051cb100 order:2 compound_mapcount:0 compound_pincount:0
[ 77.026816][ T6535] flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff)
[ 77.034882][ T6535] raw: 057ff00000010200 0000000000000000 dead000000000001 ffff888010c41c80
[ 77.043459][ T6535] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
[ 77.052025][ T6535] page dumped because: kasan: bad access detected
[ 77.058420][ T6535] page_owner tracks the page as allocated
[ 77.064116][ T6535] page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52800(GFP_NOWAIT|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, ts 8095160016, free_ts 0
[ 77.079917][ T6535] get_page_from_freelist+0xa72/0x2f40
[ 77.085378][ T6535] __alloc_pages+0x1b2/0x500
[ 77.090053][ T6535] alloc_page_interleave+0x1e/0x200
[ 77.095338][ T6535] alloc_pages+0x29f/0x300
[ 77.099755][ T6535] new_slab+0x261/0x460
[ 77.103910][ T6535] ___slab_alloc+0x798/0xf30
[ 77.108509][ T6535] __slab_alloc.constprop.0+0x4d/0xa0
[ 77.113880][ T6535] kmem_cache_alloc_node_trace+0x116/0x310
[ 77.119683][ T6535] iolatency_pd_alloc+0xb8/0x1b0
[ 77.124616][ T6535] blkcg_activate_policy+0x232/0xc00
[ 77.129897][ T6535] blk_iolatency_init+0x1aa/0x380
[ 77.135197][ T6535] blkcg_init_queue+0x194/0x780
[ 77.140059][ T6535] blk_alloc_queue+0x44c/0x620
[ 77.144822][ T6535] __blk_mq_alloc_disk+0x4c/0x160
[ 77.149840][ T6535] loop_add+0x339/0x900
[ 77.154006][ T6535] loop_init+0x1f4/0x216
[ 77.158243][ T6535] page_owner free stack trace missing
[ 77.163592][ T6535]
[ 77.165920][ T6535] Memory state around the buggy address:
[ 77.171533][ T6535] ffff8881472c5400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 77.179617][ T6535] ffff8881472c5480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 77.187668][ T6535] >ffff8881472c5500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 77.195714][ T6535] ^
[ 77.202026][ T6535] ffff8881472c5580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 77.210078][ T6535] ffff8881472c5600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 77.218443][ T6535] ==================================================================
[ 77.229093][ T6535] Kernel panic - not syncing: panic_on_warn set ...
[ 77.235715][ T6535] CPU: 0 PID: 6535 Comm: syz-executor Tainted: G B 5.16.0-rc2-next-20211129-syzkaller #0
[ 77.247007][ T6535] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 77.257070][ T6535] Call Trace:
[ 77.260397][ T6535]
[ 77.263382][ T6535] dump_stack_lvl+0xcd/0x134
[ 77.268023][ T6535] panic+0x2b0/0x6dd
[ 77.272025][ T6535] ? __warn_printk+0xf3/0xf3
[ 77.276644][ T6535] ? preempt_schedule_common+0x59/0xc0
[ 77.282523][ T6535] ? up_write+0x3ac/0x470
[ 77.286881][ T6535] ? preempt_schedule_thunk+0x16/0x18
[ 77.292254][ T6535] ? trace_hardirqs_on+0x38/0x1c0
[ 77.297356][ T6535] ? trace_hardirqs_on+0x51/0x1c0
[ 77.302379][ T6535] ? up_write+0x3ac/0x470
[ 77.306723][ T6535] ? up_write+0x3ac/0x470
[ 77.311049][ T6535] end_report.cold+0x63/0x6f
[ 77.315647][ T6535] kasan_report.cold+0x71/0xdf
[ 77.320438][ T6535] ? up_write+0x3ac/0x470
[ 77.324846][ T6535] up_write+0x3ac/0x470
[ 77.328998][ T6535] cgroup_setup_root+0x3a6/0xad0
[ 77.333940][ T6535] ? rebind_subsystems+0x10e0/0x10e0
[ 77.339223][ T6535] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80
[ 77.345462][ T6535] cgroup1_get_tree+0xd33/0x1390
[ 77.350411][ T6535] vfs_get_tree+0x89/0x2f0
[ 77.354826][ T6535] path_mount+0x1320/0x1fa0
[ 77.359342][ T6535] ? kmem_cache_free+0xba/0x4a0
[ 77.364207][ T6535] ? finish_automount+0xaf0/0xaf0
[ 77.369420][ T6535] ? putname+0xfe/0x140
[ 77.373587][ T6535] __x64_sys_mount+0x27f/0x300
[ 77.378383][ T6535] ? copy_mnt_ns+0xae0/0xae0
[ 77.382969][ T6535] ? syscall_enter_from_user_mode+0x21/0x70
[ 77.388897][ T6535] do_syscall_64+0x35/0xb0
[ 77.393406][ T6535] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 77.399468][ T6535] RIP: 0033:0x7fd22140301a
[ 77.404055][ T6535] Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
[ 77.423837][ T6535] RSP: 002b:00007ffc25f03ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
[ 77.433025][ T6535] RAX: ffffffffffffffda RBX: 00007ffc25f04038 RCX: 00007fd22140301a
[ 77.440999][ T6535] RDX: 00007fd221465fd6 RSI: 00007fd22145c29a RDI: 00007fd22145ad71
[ 77.448970][ T6535] RBP: 00007fd22145c29a R08: 00007fd22145c3f7 R09: 0000000000000026
[ 77.456927][ T6535] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc25f03eb0
[ 77.465003][ T6535] R13: 00007ffc25f04058 R14: 00007ffc25f03f80 R15: 00007fd22145c3f1
[ 77.473067][ T6535]
[ 77.476396][ T6535] Kernel Offset: disabled
[ 77.480793][ T6535] Rebooting in 86400 seconds..