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BUG: KCSAN: data-race in generic_fillattr / touch_atime

read to 0xffff888115ee3258 of 4 bytes by task 11383 on cpu 0:
 inode_get_atime_nsec include/linux/fs.h:1595 [inline]
 inode_get_atime include/linux/fs.h:1601 [inline]
 generic_fillattr+0x16f/0x2f0 fs/stat.c:60
 shmem_getattr+0x17b/0x200 mm/shmem.c:1169
 vfs_getattr_nosec fs/stat.c:166 [inline]
 vfs_getattr fs/stat.c:207 [inline]
 vfs_fstat+0x1b0/0x460 fs/stat.c:229
 vfs_fstatat+0xa2/0x110 fs/stat.c:338
 __do_sys_newfstatat fs/stat.c:505 [inline]
 __se_sys_newfstatat+0x58/0x260 fs/stat.c:499
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:499
 x64_sys_call+0x141f/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:263
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff888115ee3258 of 4 bytes by task 3259 on cpu 1:
 inode_set_atime_to_ts include/linux/fs.h:1610 [inline]
 inode_update_timestamps fs/inode.c:2012 [inline]
 generic_update_time fs/inode.c:2034 [inline]
 inode_update_time fs/inode.c:2054 [inline]
 touch_atime+0x1f3/0x350 fs/inode.c:2126
 file_accessed include/linux/fs.h:2528 [inline]
 shmem_file_read_iter+0x4aa/0x550 mm/shmem.c:3201
 new_sync_read fs/read_write.c:488 [inline]
 vfs_read+0x5f6/0x720 fs/read_write.c:569
 ksys_read+0xeb/0x1b0 fs/read_write.c:712
 __do_sys_read fs/read_write.c:722 [inline]
 __se_sys_read fs/read_write.c:720 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:720
 x64_sys_call+0x27d3/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x38ab0d24 -> 0x3943a3a4

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3259 Comm: udevd Tainted: G        W          6.12.0-rc1-syzkaller-00257-g2f91ff27b0ee #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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