syzbot

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BUG: KCSAN: data-race in generic_fillattr+0xf5/0x1e0 fs/stat.c:42 and shmem_mknod+0x112/0x180

read to 0xffff888126648968 of 8 bytes by task 7280 on cpu 0:
 generic_fillattr+0xf5/0x1e0 fs/stat.c:42
 vfs_getattr_nosec+0x160/0x170 fs/stat.c:84
 vfs_getattr+0x54/0x70 fs/stat.c:118
 vfs_statx+0x102/0x190 fs/stat.c:191
 vfs_stat include/linux/fs.h:3188 [inline]
 __do_sys_newstat+0x51/0xb0 fs/stat.c:341
 __se_sys_newstat fs/stat.c:337 [inline]
 __x64_sys_newstat+0x3a/0x50 fs/stat.c:337
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff888126648968 of 8 bytes by task 7174 on cpu 1:
 shmem_mknod+0x112/0x180 mm/shmem.c:2876
 shmem_create+0x34/0x50 mm/shmem.c:2924
 lookup_open fs/namei.c:3232 [inline]
 do_last fs/namei.c:3322 [inline]
 path_openat+0x29ea/0x3530 fs/namei.c:3533
 do_filp_open+0x11e/0x1b0 fs/namei.c:3563
 do_sys_open+0x3b3/0x4f0 fs/open.c:1089
 __do_sys_open fs/open.c:1107 [inline]
 __se_sys_open fs/open.c:1102 [inline]
 __x64_sys_open+0x55/0x70 fs/open.c:1102
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7174 Comm: udevd Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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