syzbot

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BUG: KMSAN: uninit-value in strlen lib/string.c:486 [inline]
BUG: KMSAN: uninit-value in strlcpy+0x69/0x190 lib/string.c:143
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.0.0-rc1+ #9
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: memcg_kmem_cache memcg_kmem_cache_create_func
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 strlen lib/string.c:486 [inline]
 strlcpy+0x69/0x190 lib/string.c:143
 kernfs_name_locked fs/kernfs/dir.c:48 [inline]
 kernfs_name+0x18b/0x200 fs/kernfs/dir.c:188
 cgroup_name include/linux/cgroup.h:635 [inline]
 memcg_create_kmem_cache+0x2aa/0x750 mm/slab_common.c:658
 memcg_kmem_cache_create_func+0xb1/0x300 mm/memcontrol.c:2477
 process_one_work+0x1607/0x1f80 kernel/workqueue.c:2153
 worker_thread+0x111c/0x2460 kernel/workqueue.c:2296
 kthread+0x4a1/0x4e0 kernel/kthread.c:247
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:220 [inline]
 kmsan_internal_chain_origin+0x134/0x230 mm/kmsan/kmsan.c:426
 kmsan_memcpy_memmove_metadata+0xcf2/0xf10 mm/kmsan/kmsan.c:304
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:324
 __msan_memcpy+0x58/0x70 mm/kmsan/kmsan_instr.c:139
 kstrdup mm/util.c:51 [inline]
 kstrdup_const+0x18a/0x1f0 mm/util.c:70
 __kernfs_new_node+0x11f/0xae0 fs/kernfs/dir.c:630
 kernfs_new_node fs/kernfs/dir.c:695 [inline]
 kernfs_create_dir_ns+0x1c5/0x580 fs/kernfs/dir.c:1021
 kernfs_create_dir include/linux/kernfs.h:507 [inline]
 cgroup_mkdir+0x1ddc/0x3690 kernel/cgroup/cgroup.c:5048
 kernfs_iop_mkdir+0x40e/0x5d0 fs/kernfs/dir.c:1122
 vfs_mkdir+0x6a4/0x950 fs/namei.c:3816
 do_mkdirat+0x39f/0x680 fs/namei.c:3839
 __do_sys_mkdir fs/namei.c:3855 [inline]
 __se_sys_mkdir+0x76/0x90 fs/namei.c:3853
 __x64_sys_mkdir+0x3e/0x60 fs/namei.c:3853
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmem_cache_alloc+0x585/0xb60 mm/slub.c:2772
 __d_alloc+0x98/0xc30 fs/dcache.c:1599
 d_alloc+0x97/0x4f0 fs/dcache.c:1678
 __lookup_hash+0x1ab/0x510 fs/namei.c:1542
 filename_create+0x2f3/0xab0 fs/namei.c:3636
 user_path_create fs/namei.c:3693 [inline]
 do_mkdirat+0x11c/0x680 fs/namei.c:3831
 __do_sys_mkdir fs/namei.c:3855 [inline]
 __se_sys_mkdir+0x76/0x90 fs/namei.c:3853
 __x64_sys_mkdir+0x3e/0x60 fs/namei.c:3853
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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