syzbot

EXT4-fs (loop1): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
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BUG: KCSAN: data-race in __mark_inode_dirty / __mark_inode_dirty

write to 0xffff888106936170 of 8 bytes by task 5481 on cpu 0:
 __mark_inode_dirty+0x256/0x7e0 fs/fs-writeback.c:2517
 generic_update_time fs/inode.c:2004 [inline]
 inode_update_time fs/inode.c:2017 [inline]
 __file_update_time fs/inode.c:2206 [inline]
 file_modified_flags+0x309/0x340 fs/inode.c:2277
 file_modified+0x17/0x20 fs/inode.c:2293
 ext4_write_checks fs/ext4/file.c:279 [inline]
 ext4_buffered_write_iter+0x1d8/0x380 fs/ext4/file.c:295
 ext4_file_write_iter+0x29f/0xe30
 iter_file_splice_write+0x5e6/0x970 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x305/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x950 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41
 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

read to 0xffff888106936170 of 8 bytes by task 5476 on cpu 1:
 __mark_inode_dirty+0x19f/0x7e0 fs/fs-writeback.c:2508
 generic_update_time fs/inode.c:2004 [inline]
 inode_update_time fs/inode.c:2017 [inline]
 touch_atime+0x230/0x350 fs/inode.c:2089
 file_accessed include/linux/fs.h:2486 [inline]
 filemap_splice_read+0x8b0/0x920 mm/filemap.c:2950
 ext4_file_splice_read+0x95/0xc0 fs/ext4/file.c:158
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x950 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41
 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: 0x0000000000000000 -> 0x0000000000000005

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5476 Comm: syz.1.473 Not tainted 6.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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