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BUG: KCSAN: data-race in __mark_inode_dirty / writeback_single_inode

write to 0xffff888106770f70 of 8 bytes by task 31876 on cpu 0:
 writeback_single_inode+0x10e/0x4a0 fs/fs-writeback.c:1721
 sync_inode_metadata+0x56/0x80 fs/fs-writeback.c:2786
 generic_buffers_fsync_noflush+0xe4/0x120 fs/buffer.c:619
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x206/0x6c0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x111/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2625 [inline]
 ext4_buffered_write_iter+0x334/0x370 fs/ext4/file.c:305
 ext4_file_write_iter+0xd6/0x1200
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x462/0x7e0 fs/splice.c:736
 do_splice_from fs/splice.c:933 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1142
 splice_direct_to_actor+0x31d/0x690 fs/splice.c:1088
 do_splice_direct+0x10d/0x190 fs/splice.c:1194
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888106770f70 of 8 bytes by task 31878 on cpu 1:
 __mark_inode_dirty+0x58/0x7d0 fs/fs-writeback.c:2412
 mark_inode_dirty include/linux/fs.h:2266 [inline]
 dquot_alloc_space include/linux/quotaops.h:320 [inline]
 dquot_alloc_block include/linux/quotaops.h:337 [inline]
 ext4_mb_new_blocks+0x103e/0x21e0 fs/ext4/mballoc.c:6191
 ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
 ext4_ind_map_blocks+0xb3e/0x1490 fs/ext4/indirect.c:635
 ext4_map_blocks+0x6b1/0xf60 fs/ext4/inode.c:623
 _ext4_get_block+0x103/0x370 fs/ext4/inode.c:763
 ext4_get_block+0x39/0x50 fs/ext4/inode.c:780
 __block_write_begin_int+0x3c0/0xf20 fs/buffer.c:2107
 __block_write_begin+0x5e/0x110 fs/buffer.c:2157
 ext4_write_begin+0x41e/0xba0
 generic_perform_write+0x1c9/0x410 mm/filemap.c:3942
 ext4_buffered_write_iter+0x1f6/0x370 fs/ext4/file.c:299
 ext4_file_write_iter+0xd6/0x1200
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_iter_write+0x56/0x70 fs/read_write.c:901
 iter_file_splice_write+0x462/0x7e0 fs/splice.c:736
 do_splice_from fs/splice.c:933 [inline]
 direct_splice_actor+0x8a/0xb0 fs/splice.c:1142
 splice_direct_to_actor+0x31d/0x690 fs/splice.c:1088
 do_splice_direct+0x10d/0x190 fs/splice.c:1194
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000007 -> 0x0000000000000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 31878 Comm: syz-executor.2 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
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syz-executor.2 (31878) used greatest stack depth: 9376 bytes left