KCSAN: data-race in generic_fillattr / inode_set_ctime_to

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in generic_fillattr / inode_set_ctime_to_ts fs	6				5	79d	218d	0/29	auto-obsoleted due to no activity on 2025/06/21 18:02

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BUG: KCSAN: data-race in generic_fillattr / inode_set_ctime_to_ts

write to 0xffff888119c85550 of 4 bytes by task 3527 on cpu 0:
 inode_set_ctime_to_ts+0x84/0x170 fs/inode.c:2668
 inode_set_ctime_current+0x1d6/0x770 fs/inode.c:2731
 shmem_xattr_handler_set+0x1ac/0x220 mm/shmem.c:4339
 __vfs_setxattr+0x2e6/0x310 fs/xattr.c:200
 __vfs_setxattr_noperm+0xe8/0x410 fs/xattr.c:234
 __vfs_setxattr_locked+0x1af/0x1d0 fs/xattr.c:295
 vfs_setxattr+0x132/0x270 fs/xattr.c:321
 do_setxattr fs/xattr.c:636 [inline]
 filename_setxattr+0x1ad/0x400 fs/xattr.c:665
 path_setxattrat+0x2c9/0x310 fs/xattr.c:713
 __do_sys_lsetxattr fs/xattr.c:754 [inline]
 __se_sys_lsetxattr fs/xattr.c:750 [inline]
 __x64_sys_lsetxattr+0x71/0x90 fs/xattr.c:750
 x64_sys_call+0x1e36/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:190
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888119c85550 of 4 bytes by task 3294 on cpu 1:
 inode_get_ctime_nsec include/linux/fs.h:1748 [inline]
 inode_get_ctime include/linux/fs.h:1754 [inline]
 generic_fillattr+0x1d1/0x340 fs/stat.c:101
 shmem_getattr+0x181/0x200 mm/shmem.c:1262
 vfs_getattr_nosec+0x146/0x1e0 fs/stat.c:213
 vfs_getattr fs/stat.c:262 [inline]
 vfs_statx_path fs/stat.c:299 [inline]
 vfs_statx+0x113/0x390 fs/stat.c:356
 vfs_fstatat+0x115/0x170 fs/stat.c:375
 __do_sys_newfstatat fs/stat.c:542 [inline]
 __se_sys_newfstatat+0x55/0x260 fs/stat.c:536
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:536
 x64_sys_call+0x2c22/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:263
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x2cba2463 -> 0x368d321e

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3294 Comm: udevd Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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