syzbot

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BUG: KMSAN: uninit-value in trace_trigger_soft_disabled include/linux/trace_events.h:609 [inline]
BUG: KMSAN: uninit-value in trace_event_raw_event_emulate_vsyscall+0x121/0x3b0 include/trace/../../arch/x86/entry/vsyscall//vsyscall_trace.h:10
CPU: 1 PID: 13303 Comm: kworker/u4:30 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 trace_trigger_soft_disabled include/linux/trace_events.h:609 [inline]
 trace_event_raw_event_emulate_vsyscall+0x121/0x3b0 include/trace/../../arch/x86/entry/vsyscall//vsyscall_trace.h:10
 __exc_page_fault+0xac/0x450 arch/x86/mm/fault.c:1428
 exc_page_fault+0x45/0x50 arch/x86/mm/fault.c:1390
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:550
RIP: 0010:vdso_mremap+0x2d0/0x460 arch/x86/entry/vdso/vma.c:99
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
RSP: 0018:ffff8881a57e7c00 EFLAGS: 00010097
RAX: ffff88821fdb2cd8 RBX: 0000000000000000 RCX: 000000021fd13cd8
RDX: ffff88821fd13cd8 RSI: ffff8881c42c9e80 RDI: ffff8881a57dbd00
RBP: ffff8881a57e7c60 R08: ffffea000000000f R09: ffff88812fffa000
R10: 0000000000000004 R11: 0000000000000000 R12: ffff88812fd94cd8
R13: ffff8881a57dc6d8 R14: ffff8881a57dbd00 R15: ffff8881a57dc0f0
 preempt_schedule_common kernel/sched/core.c:4351 [inline]
 _cond_resched+0x43/0xa0 kernel/sched/core.c:5737
 process_one_work+0x18c6/0x2140 kernel/workqueue.c:2295
 worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
 kthread+0x551/0x590 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
 kstrdup mm/util.c:62 [inline]
 kstrdup_const+0x1cc/0x240 mm/util.c:82
 __kernfs_new_node+0x11f/0xcd0 fs/kernfs/dir.c:623
 kernfs_new_node fs/kernfs/dir.c:689 [inline]
 kernfs_create_dir_ns+0x1d6/0x5d0 fs/kernfs/dir.c:1026
 sysfs_create_dir_ns+0x26f/0x670 fs/sysfs/dir.c:59
 create_dir lib/kobject.c:89 [inline]
 kobject_add_internal+0x1062/0x1c90 lib/kobject.c:255
 kobject_add_varg lib/kobject.c:390 [inline]
 kobject_add+0x34b/0x520 lib/kobject.c:442
 blk_mq_register_hctx block/blk-mq-sysfs.c:257 [inline]
 __blk_mq_register_dev+0x5ae/0xbc0 block/blk-mq-sysfs.c:329
 blk_register_queue+0x60d/0x940 block/blk-sysfs.c:992
 __device_add_disk+0x10ef/0x24c0 block/genhd.c:834
 device_add_disk+0x90/0xa0 block/genhd.c:850
 add_disk include/linux/genhd.h:296 [inline]
 nbd_dev_add+0xbf3/0xee0 drivers/block/nbd.c:1747
 nbd_init+0x3c6/0x4a3 drivers/block/nbd.c:2409
 do_one_initcall+0x4fb/0x9f0 init/main.c:1202
 do_initcall_level+0x336/0x3c5 init/main.c:1275
 do_initcalls+0x18d/0x24f init/main.c:1291
 do_basic_setup+0x33/0x36 init/main.c:1311
 kernel_init_freeable+0x242/0x40d init/main.c:1508
 kernel_init+0x1f/0x840 init/main.c:1402
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
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