EXT4-fs (loop4): re-mounted. Opts: 
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BUG: KMSAN: uninit-value in qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
CPU: 1 PID: 15144 Comm: syz-executor.4 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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:122
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:201
 qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
 v2r1_mem2diskdqb+0x43d/0x710 fs/quota/quota_v2.c:285
 qtree_write_dquot+0x226/0x870 fs/quota/quota_tree.c:394
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_acquire+0x46e/0x760 fs/quota/dquot.c:443
 ext4_acquire_dquot+0x422/0x550 fs/ext4/super.c:5950
 dqget+0x14be/0x1c50 fs/quota/dquot.c:901
 __dquot_initialize+0x9d6/0x19e0 fs/quota/dquot.c:1479
 dquot_initialize+0x4d/0x60 fs/quota/dquot.c:1537
 ext4_setattr+0x984/0x2f70 fs/ext4/inode.c:5277
 notify_change+0x1efd/0x2570 fs/attr.c:336
 chown_common+0x71e/0xb20 fs/open.c:674
 vfs_fchown fs/open.c:741 [inline]
 ksys_fchown+0x246/0x390 fs/open.c:752
 __do_sys_fchown16 kernel/uid16.c:35 [inline]
 __se_sys_fchown16+0x185/0x1b0 kernel/uid16.c:33
 __ia32_sys_fchown16+0x4a/0x70 kernel/uid16.c:33
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f4a549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55230cc EFLAGS: 00000296 ORIG_RAX: 000000000000005f
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 000000000000ee00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:129 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:112
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2903 [inline]
 slab_alloc mm/slub.c:2912 [inline]
 __kmalloc+0x282/0x490 mm/slub.c:3978
 kmalloc include/linux/slab.h:559 [inline]
 getdqbuf+0x4e/0xe0 fs/quota/quota_tree.c:52
 qtree_write_dquot+0xf2/0x870 fs/quota/quota_tree.c:378
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_acquire+0x46e/0x760 fs/quota/dquot.c:443
 ext4_acquire_dquot+0x422/0x550 fs/ext4/super.c:5950
 dqget+0x14be/0x1c50 fs/quota/dquot.c:901
 __dquot_initialize+0x9d6/0x19e0 fs/quota/dquot.c:1479
 dquot_initialize+0x4d/0x60 fs/quota/dquot.c:1537
 ext4_setattr+0x984/0x2f70 fs/ext4/inode.c:5277
 notify_change+0x1efd/0x2570 fs/attr.c:336
 chown_common+0x71e/0xb20 fs/open.c:674
 vfs_fchown fs/open.c:741 [inline]
 ksys_fchown+0x246/0x390 fs/open.c:752
 __do_sys_fchown16 kernel/uid16.c:35 [inline]
 __se_sys_fchown16+0x185/0x1b0 kernel/uid16.c:33
 __ia32_sys_fchown16+0x4a/0x70 kernel/uid16.c:33
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
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