WARNING: held lock freed in kernfs_destroy_root cgroup: Unknown subsys name 'net' ========================= WARNING: held lock freed! 5.16.0-rc3-next-20211201-syzkaller #0 Not tainted ------------------------- syz-executor/6589 is freeing memory ffff8880224d8000-ffff8880224d81ff, with a lock still held there! ffff8880224d8148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_remove fs/kernfs/dir.c:1396 [inline] ffff8880224d8148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_destroy_root+0x81/0xb0 fs/kernfs/dir.c:964 2 locks held by syz-executor/6589: #0: ffffffff8b7c4e48 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock_and_drain_offline+0xa5/0x900 kernel/cgroup/cgroup.c:2998 #1: ffff8880224d8148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_remove fs/kernfs/dir.c:1396 [inline] #1: ffff8880224d8148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_destroy_root+0x81/0xb0 fs/kernfs/dir.c:964 stack backtrace: CPU: 1 PID: 6589 Comm: syz-executor Not tainted 5.16.0-rc3-next-20211201-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_freed_lock_bug kernel/locking/lockdep.c:6388 [inline] debug_check_no_locks_freed.cold+0x9d/0xa9 kernel/locking/lockdep.c:6421 slab_free_hook mm/slub.c:1695 [inline] slab_free_freelist_hook+0x73/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kfree+0xe0/0x430 mm/slub.c:4561 kernfs_put.part.0+0x331/0x540 fs/kernfs/dir.c:548 kernfs_put+0x42/0x50 fs/kernfs/dir.c:513 __kernfs_remove+0x7a3/0xb20 fs/kernfs/dir.c:1382 kernfs_remove fs/kernfs/dir.c:1397 [inline] kernfs_destroy_root+0x89/0xb0 fs/kernfs/dir.c:964 cgroup_setup_root+0x3a6/0xad0 kernel/cgroup/cgroup.c:2077 cgroup1_root_to_use kernel/cgroup/cgroup-v1.c:1194 [inline] cgroup1_get_tree+0xd33/0x1390 kernel/cgroup/cgroup-v1.c:1211 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:3004 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3334 do_mount fs/namespace.c:3347 [inline] __do_sys_mount fs/namespace.c:3555 [inline] __se_sys_mount fs/namespace.c:3532 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3532 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7effbf876f6a 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 RSP: 002b:00007fff2efc1228 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fff2efc13b8 RCX: 00007effbf876f6a RDX: 00007effbf8d9e6c RSI: 00007effbf8d01b1 RDI: 00007effbf8ceca1 RBP: 00007effbf8d01b1 R08: 00007effbf8d030e R09: 0000000000000026 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2efc1230 R13: 00007fff2efc13d8 R14: 00007fff2efc1300 R15: 00007effbf8d0308 ================================================================== BUG: KASAN: use-after-free in __up_write kernel/locking/rwsem.c:1318 [inline] BUG: KASAN: use-after-free in up_write+0x3ac/0x470 kernel/locking/rwsem.c:1576 Read of size 8 at addr ffff8880224d8140 by task syz-executor/6589 CPU: 1 PID: 6589 Comm: syz-executor Not tainted 5.16.0-rc3-next-20211201-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xa5/0x3ed mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 __up_write kernel/locking/rwsem.c:1318 [inline] up_write+0x3ac/0x470 kernel/locking/rwsem.c:1576 cgroup_setup_root+0x3a6/0xad0 kernel/cgroup/cgroup.c:2077 cgroup1_root_to_use kernel/cgroup/cgroup-v1.c:1194 [inline] cgroup1_get_tree+0xd33/0x1390 kernel/cgroup/cgroup-v1.c:1211 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:3004 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3334 do_mount fs/namespace.c:3347 [inline] __do_sys_mount fs/namespace.c:3555 [inline] __se_sys_mount fs/namespace.c:3532 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3532 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7effbf876f6a 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 RSP: 002b:00007fff2efc1228 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fff2efc13b8 RCX: 00007effbf876f6a RDX: 00007effbf8d9e6c RSI: 00007effbf8d01b1 RDI: 00007effbf8ceca1 RBP: 00007effbf8d01b1 R08: 00007effbf8d030e R09: 0000000000000026 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2efc1230 R13: 00007fff2efc13d8 R14: 00007fff2efc1300 R15: 00007effbf8d0308 Allocated by task 6589: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:724 [inline] kernfs_create_root+0x4c/0x410 fs/kernfs/dir.c:913 cgroup_setup_root+0x243/0xad0 kernel/cgroup/cgroup.c:2018 cgroup1_root_to_use kernel/cgroup/cgroup-v1.c:1194 [inline] cgroup1_get_tree+0xd33/0x1390 kernel/cgroup/cgroup-v1.c:1211 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:3004 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3334 do_mount fs/namespace.c:3347 [inline] __do_sys_mount fs/namespace.c:3555 [inline] __se_sys_mount fs/namespace.c:3532 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3532 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 6589: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0x103/0x170 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kfree+0xe0/0x430 mm/slub.c:4561 kernfs_put.part.0+0x331/0x540 fs/kernfs/dir.c:548 kernfs_put+0x42/0x50 fs/kernfs/dir.c:513 __kernfs_remove+0x7a3/0xb20 fs/kernfs/dir.c:1382 kernfs_remove fs/kernfs/dir.c:1397 [inline] kernfs_destroy_root+0x89/0xb0 fs/kernfs/dir.c:964 cgroup_setup_root+0x3a6/0xad0 kernel/cgroup/cgroup.c:2077 cgroup1_root_to_use kernel/cgroup/cgroup-v1.c:1194 [inline] cgroup1_get_tree+0xd33/0x1390 kernel/cgroup/cgroup-v1.c:1211 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:3004 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3334 do_mount fs/namespace.c:3347 [inline] __do_sys_mount fs/namespace.c:3555 [inline] __se_sys_mount fs/namespace.c:3532 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3532 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8880224d8000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 320 bytes inside of 512-byte region [ffff8880224d8000, ffff8880224d8200) The buggy address belongs to the page: page:ffffea0000893600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x224d8 head:ffffea0000893600 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010841c80 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6018, ts 54045900514, free_ts 39570114274 prep_new_page mm/page_alloc.c:2433 [inline] get_page_from_freelist+0xa72/0x2f40 mm/page_alloc.c:4164 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5376 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2193 alloc_slab_page mm/slub.c:1793 [inline] allocate_slab mm/slub.c:1930 [inline] new_slab+0x261/0x460 mm/slub.c:1993 ___slab_alloc+0x798/0xf30 mm/slub.c:3022 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109 slab_alloc_node mm/slub.c:3200 [inline] slab_alloc mm/slub.c:3242 [inline] __kmalloc+0x2fb/0x340 mm/slub.c:4419 kmalloc include/linux/slab.h:595 [inline] load_elf_phdrs+0x103/0x210 fs/binfmt_elf.c:479 load_elf_binary+0x1dc/0x4da0 fs/binfmt_elf.c:859 search_binary_handler fs/exec.c:1725 [inline] exec_binprm fs/exec.c:1766 [inline] bprm_execve fs/exec.c:1835 [inline] bprm_execve+0x7ef/0x19b0 fs/exec.c:1797 do_execveat_common+0x5e3/0x780 fs/exec.c:1924 do_execve fs/exec.c:1992 [inline] __do_sys_execve fs/exec.c:2068 [inline] __se_sys_execve fs/exec.c:2063 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:2063 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1351 [inline] free_pcp_prepare+0x414/0xb60 mm/page_alloc.c:1403 free_unref_page_prepare mm/page_alloc.c:3324 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3403 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xf0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:259 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:3234 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags+0x9a/0xe0 include/linux/audit.h:323 user_path_at_empty+0x2b/0x60 fs/namei.c:2850 do_readlinkat+0xcd/0x2f0 fs/stat.c:443 __do_sys_readlinkat fs/stat.c:470 [inline] __se_sys_readlinkat fs/stat.c:467 [inline] __x64_sys_readlinkat+0x93/0xf0 fs/stat.c:467 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff8880224d8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880224d8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880224d8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880224d8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880224d8200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Warning: Permanently added '10.128.10.17' (ECDSA) to the list of known hosts. 2021/12/01 13:57:34 fuzzer started 2021/12/01 13:57:34 connecting to host at 10.128.0.169:46367 2021/12/01 13:57:34 checking machine... 2021/12/01 13:57:34 checking revisions... 2021/12/01 13:57:35 testing simple program... syzkaller login: [ 76.620213][ T6589] cgroup: Unknown subsys name 'net' [ 76.626451][ T6589] [ 76.628787][ T6589] ========================= [ 76.633507][ T6589] WARNING: held lock freed! [ 76.638077][ T6589] 5.16.0-rc3-next-20211201-syzkaller #0 Not tainted [ 76.644731][ T6589] ------------------------- [ 76.649578][ T6589] syz-executor/6589 is freeing memory ffff8880224d8000-ffff8880224d81ff, with a lock still held there! [ 76.660862][ T6589] ffff8880224d8148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_destroy_root+0x81/0xb0 [ 76.670612][ T6589] 2 locks held by syz-executor/6589: [ 76.675981][ T6589] #0: ffffffff8b7c4e48 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock_and_drain_offline+0xa5/0x900 [ 76.686623][ T6589] #1: ffff8880224d8148 (&root->kernfs_rwsem){++++}-{3:3}, at: kernfs_destroy_root+0x81/0xb0 [ 76.696808][ T6589] [ 76.696808][ T6589] stack backtrace: [ 76.702682][ T6589] CPU: 1 PID: 6589 Comm: syz-executor Not tainted 5.16.0-rc3-next-20211201-syzkaller #0 [ 76.712656][ T6589] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 76.722973][ T6589] Call Trace: [ 76.726255][ T6589] [ 76.729190][ T6589] dump_stack_lvl+0xcd/0x134 [ 76.733864][ T6589] debug_check_no_locks_freed.cold+0x9d/0xa9 [ 76.739858][ T6589] ? lockdep_hardirqs_on+0x79/0x100 [ 76.745730][ T6589] slab_free_freelist_hook+0x73/0x1c0 [ 76.751276][ T6589] ? kernfs_put.part.0+0x331/0x540 [ 76.756509][ T6589] kfree+0xe0/0x430 [ 76.760482][ T6589] ? kmem_cache_free+0xba/0x4a0 [ 76.765608][ T6589] ? rwlock_bug.part.0+0x90/0x90 [ 76.770856][ T6589] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 76.777202][ T6589] kernfs_put.part.0+0x331/0x540 [ 76.782143][ T6589] kernfs_put+0x42/0x50 [ 76.786291][ T6589] __kernfs_remove+0x7a3/0xb20 [ 76.791377][ T6589] ? kernfs_next_descendant_post+0x2f0/0x2f0 [ 76.797451][ T6589] ? down_write+0xde/0x150 [ 76.802567][ T6589] ? down_write_killable_nested+0x180/0x180 [ 76.808556][ T6589] kernfs_destroy_root+0x89/0xb0 [ 76.813591][ T6589] cgroup_setup_root+0x3a6/0xad0 [ 76.818726][ T6589] ? rebind_subsystems+0x10e0/0x10e0 [ 76.824037][ T6589] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80 [ 76.830297][ T6589] cgroup1_get_tree+0xd33/0x1390 [ 76.835281][ T6589] vfs_get_tree+0x89/0x2f0 [ 76.840062][ T6589] path_mount+0x1320/0x1fa0 [ 76.844801][ T6589] ? kmem_cache_free+0xba/0x4a0 [ 76.849958][ T6589] ? finish_automount+0xaf0/0xaf0 [ 76.855002][ T6589] ? putname+0xfe/0x140 [ 76.859331][ T6589] __x64_sys_mount+0x27f/0x300 [ 76.864981][ T6589] ? copy_mnt_ns+0xae0/0xae0 [ 76.869574][ T6589] ? syscall_enter_from_user_mode+0x21/0x70 [ 76.875558][ T6589] do_syscall_64+0x35/0xb0 [ 76.880459][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 76.887070][ T6589] RIP: 0033:0x7effbf876f6a [ 76.891653][ T6589] 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 [ 76.911683][ T6589] RSP: 002b:00007fff2efc1228 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 76.920263][ T6589] RAX: ffffffffffffffda RBX: 00007fff2efc13b8 RCX: 00007effbf876f6a [ 76.928322][ T6589] RDX: 00007effbf8d9e6c RSI: 00007effbf8d01b1 RDI: 00007effbf8ceca1 [ 76.936396][ T6589] RBP: 00007effbf8d01b1 R08: 00007effbf8d030e R09: 0000000000000026 [ 76.944368][ T6589] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2efc1230 [ 76.952552][ T6589] R13: 00007fff2efc13d8 R14: 00007fff2efc1300 R15: 00007effbf8d0308 [ 76.960539][ T6589] [ 76.963859][ T6589] ================================================================== [ 76.972009][ T6589] BUG: KASAN: use-after-free in up_write+0x3ac/0x470 [ 76.978793][ T6589] Read of size 8 at addr ffff8880224d8140 by task syz-executor/6589 [ 76.986863][ T6589] [ 76.989178][ T6589] CPU: 1 PID: 6589 Comm: syz-executor Not tainted 5.16.0-rc3-next-20211201-syzkaller #0 [ 76.998884][ T6589] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 77.008943][ T6589] Call Trace: [ 77.012229][ T6589] [ 77.015153][ T6589] dump_stack_lvl+0xcd/0x134 [ 77.019745][ T6589] print_address_description.constprop.0.cold+0xa5/0x3ed [ 77.026943][ T6589] ? up_write+0x3ac/0x470 [ 77.031269][ T6589] ? up_write+0x3ac/0x470 [ 77.035593][ T6589] kasan_report.cold+0x83/0xdf [ 77.040355][ T6589] ? up_write+0x3ac/0x470 [ 77.044679][ T6589] up_write+0x3ac/0x470 [ 77.049004][ T6589] cgroup_setup_root+0x3a6/0xad0 [ 77.053956][ T6589] ? rebind_subsystems+0x10e0/0x10e0 [ 77.059244][ T6589] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80 [ 77.065589][ T6589] cgroup1_get_tree+0xd33/0x1390 [ 77.070635][ T6589] vfs_get_tree+0x89/0x2f0 [ 77.075222][ T6589] path_mount+0x1320/0x1fa0 [ 77.079899][ T6589] ? kmem_cache_free+0xba/0x4a0 [ 77.084765][ T6589] ? finish_automount+0xaf0/0xaf0 [ 77.089988][ T6589] ? putname+0xfe/0x140 [ 77.094299][ T6589] __x64_sys_mount+0x27f/0x300 [ 77.099340][ T6589] ? copy_mnt_ns+0xae0/0xae0 [ 77.104399][ T6589] ? syscall_enter_from_user_mode+0x21/0x70 [ 77.110665][ T6589] do_syscall_64+0x35/0xb0 [ 77.115204][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 77.121276][ T6589] RIP: 0033:0x7effbf876f6a [ 77.125958][ T6589] 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 [ 77.146171][ T6589] RSP: 002b:00007fff2efc1228 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 77.154598][ T6589] RAX: ffffffffffffffda RBX: 00007fff2efc13b8 RCX: 00007effbf876f6a [ 77.162566][ T6589] RDX: 00007effbf8d9e6c RSI: 00007effbf8d01b1 RDI: 00007effbf8ceca1 [ 77.171080][ T6589] RBP: 00007effbf8d01b1 R08: 00007effbf8d030e R09: 0000000000000026 [ 77.179399][ T6589] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2efc1230 [ 77.187537][ T6589] R13: 00007fff2efc13d8 R14: 00007fff2efc1300 R15: 00007effbf8d0308 [ 77.195920][ T6589] [ 77.198962][ T6589] [ 77.201419][ T6589] Allocated by task 6589: [ 77.205846][ T6589] kasan_save_stack+0x1e/0x50 [ 77.210701][ T6589] __kasan_kmalloc+0xa9/0xd0 [ 77.215542][ T6589] kernfs_create_root+0x4c/0x410 [ 77.220569][ T6589] cgroup_setup_root+0x243/0xad0 [ 77.225507][ T6589] cgroup1_get_tree+0xd33/0x1390 [ 77.230451][ T6589] vfs_get_tree+0x89/0x2f0 [ 77.234874][ T6589] path_mount+0x1320/0x1fa0 [ 77.239549][ T6589] __x64_sys_mount+0x27f/0x300 [ 77.244591][ T6589] do_syscall_64+0x35/0xb0 [ 77.249002][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 77.255240][ T6589] [ 77.257648][ T6589] Freed by task 6589: [ 77.261639][ T6589] kasan_save_stack+0x1e/0x50 [ 77.266405][ T6589] kasan_set_track+0x21/0x30 [ 77.271270][ T6589] kasan_set_free_info+0x20/0x30 [ 77.276207][ T6589] __kasan_slab_free+0x103/0x170 [ 77.281318][ T6589] slab_free_freelist_hook+0x8b/0x1c0 [ 77.286776][ T6589] kfree+0xe0/0x430 [ 77.290581][ T6589] kernfs_put.part.0+0x331/0x540 [ 77.295605][ T6589] kernfs_put+0x42/0x50 [ 77.299857][ T6589] __kernfs_remove+0x7a3/0xb20 [ 77.304643][ T6589] kernfs_destroy_root+0x89/0xb0 [ 77.309578][ T6589] cgroup_setup_root+0x3a6/0xad0 [ 77.314515][ T6589] cgroup1_get_tree+0xd33/0x1390 [ 77.319540][ T6589] vfs_get_tree+0x89/0x2f0 [ 77.323955][ T6589] path_mount+0x1320/0x1fa0 [ 77.328542][ T6589] __x64_sys_mount+0x27f/0x300 [ 77.333670][ T6589] do_syscall_64+0x35/0xb0 [ 77.338354][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 77.344256][ T6589] [ 77.346659][ T6589] The buggy address belongs to the object at ffff8880224d8000 [ 77.346659][ T6589] which belongs to the cache kmalloc-512 of size 512 [ 77.360704][ T6589] The buggy address is located 320 bytes inside of [ 77.360704][ T6589] 512-byte region [ffff8880224d8000, ffff8880224d8200) [ 77.374178][ T6589] The buggy address belongs to the page: [ 77.379808][ T6589] page:ffffea0000893600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x224d8 [ 77.390212][ T6589] head:ffffea0000893600 order:2 compound_mapcount:0 compound_pincount:0 [ 77.398548][ T6589] flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) [ 77.406535][ T6589] raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010841c80 [ 77.415388][ T6589] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 [ 77.423956][ T6589] page dumped because: kasan: bad access detected [ 77.430350][ T6589] page_owner tracks the page as allocated [ 77.436060][ T6589] page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6018, ts 54045900514, free_ts 39570114274 [ 77.455168][ T6589] get_page_from_freelist+0xa72/0x2f40 [ 77.460634][ T6589] __alloc_pages+0x1b2/0x500 [ 77.465482][ T6589] alloc_pages+0x1a7/0x300 [ 77.469905][ T6589] new_slab+0x261/0x460 [ 77.474076][ T6589] ___slab_alloc+0x798/0xf30 [ 77.478750][ T6589] __slab_alloc.constprop.0+0x4d/0xa0 [ 77.484118][ T6589] __kmalloc+0x2fb/0x340 [ 77.488370][ T6589] load_elf_phdrs+0x103/0x210 [ 77.493068][ T6589] load_elf_binary+0x1dc/0x4da0 [ 77.498206][ T6589] bprm_execve+0x7ef/0x19b0 [ 77.502716][ T6589] do_execveat_common+0x5e3/0x780 [ 77.507914][ T6589] __x64_sys_execve+0x8f/0xc0 [ 77.512589][ T6589] do_syscall_64+0x35/0xb0 [ 77.517101][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 77.522990][ T6589] page last free stack trace: [ 77.527821][ T6589] free_pcp_prepare+0x414/0xb60 [ 77.532696][ T6589] free_unref_page+0x19/0x690 [ 77.537379][ T6589] qlist_free_all+0x5a/0xf0 [ 77.541882][ T6589] kasan_quarantine_reduce+0x180/0x200 [ 77.547427][ T6589] __kasan_slab_alloc+0xa2/0xc0 [ 77.552286][ T6589] kmem_cache_alloc+0x202/0x3a0 [ 77.557154][ T6589] getname_flags.part.0+0x50/0x4f0 [ 77.562352][ T6589] getname_flags+0x9a/0xe0 [ 77.566773][ T6589] user_path_at_empty+0x2b/0x60 [ 77.571639][ T6589] do_readlinkat+0xcd/0x2f0 [ 77.576221][ T6589] __x64_sys_readlinkat+0x93/0xf0 [ 77.581324][ T6589] do_syscall_64+0x35/0xb0 [ 77.585735][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 77.591624][ T6589] [ 77.593937][ T6589] Memory state around the buggy address: [ 77.599553][ T6589] ffff8880224d8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.607778][ T6589] ffff8880224d8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.616208][ T6589] >ffff8880224d8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.624266][ T6589] ^ [ 77.630411][ T6589] ffff8880224d8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 77.638479][ T6589] ffff8880224d8200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 77.646977][ T6589] ================================================================== [ 77.662851][ T6589] Kernel panic - not syncing: panic_on_warn set ... [ 77.669549][ T6589] CPU: 0 PID: 6589 Comm: syz-executor Tainted: G B 5.16.0-rc3-next-20211201-syzkaller #0 [ 77.680759][ T6589] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 77.690825][ T6589] Call Trace: [ 77.694108][ T6589] [ 77.697042][ T6589] dump_stack_lvl+0xcd/0x134 [ 77.701737][ T6589] panic+0x2b0/0x6dd [ 77.706095][ T6589] ? __warn_printk+0xf3/0xf3 [ 77.710783][ T6589] ? preempt_schedule_common+0x59/0xc0 [ 77.716252][ T6589] ? up_write+0x3ac/0x470 [ 77.720664][ T6589] ? preempt_schedule_thunk+0x16/0x18 [ 77.727433][ T6589] ? trace_hardirqs_on+0x38/0x1c0 [ 77.732833][ T6589] ? trace_hardirqs_on+0x51/0x1c0 [ 77.737871][ T6589] ? up_write+0x3ac/0x470 [ 77.742490][ T6589] ? up_write+0x3ac/0x470 [ 77.746919][ T6589] end_report.cold+0x63/0x6f [ 77.751527][ T6589] kasan_report.cold+0x71/0xdf [ 77.756304][ T6589] ? up_write+0x3ac/0x470 [ 77.760633][ T6589] up_write+0x3ac/0x470 [ 77.764796][ T6589] cgroup_setup_root+0x3a6/0xad0 [ 77.769754][ T6589] ? rebind_subsystems+0x10e0/0x10e0 [ 77.775062][ T6589] ? __sanitizer_cov_trace_const_cmp1+0x22/0x80 [ 77.781320][ T6589] cgroup1_get_tree+0xd33/0x1390 [ 77.786871][ T6589] vfs_get_tree+0x89/0x2f0 [ 77.791290][ T6589] path_mount+0x1320/0x1fa0 [ 77.795805][ T6589] ? kmem_cache_free+0xba/0x4a0 [ 77.801182][ T6589] ? finish_automount+0xaf0/0xaf0 [ 77.806217][ T6589] ? putname+0xfe/0x140 [ 77.810458][ T6589] __x64_sys_mount+0x27f/0x300 [ 77.815238][ T6589] ? copy_mnt_ns+0xae0/0xae0 [ 77.820199][ T6589] ? syscall_enter_from_user_mode+0x21/0x70 [ 77.826104][ T6589] do_syscall_64+0x35/0xb0 [ 77.830625][ T6589] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 77.836627][ T6589] RIP: 0033:0x7effbf876f6a [ 77.841055][ T6589] 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 [ 77.860675][ T6589] RSP: 002b:00007fff2efc1228 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 77.869102][ T6589] RAX: ffffffffffffffda RBX: 00007fff2efc13b8 RCX: 00007effbf876f6a [ 77.877155][ T6589] RDX: 00007effbf8d9e6c RSI: 00007effbf8d01b1 RDI: 00007effbf8ceca1 [ 77.885568][ T6589] RBP: 00007effbf8d01b1 R08: 00007effbf8d030e R09: 0000000000000026 [ 77.893558][ T6589] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2efc1230 [ 77.901611][ T6589] R13: 00007fff2efc13d8 R14: 00007fff2efc1300 R15: 00007effbf8d0308 [ 77.909707][ T6589] [ 77.912777][ T6589] Kernel Offset: disabled [ 77.917142][ T6589] Rebooting in 86400 seconds..