KCSAN: data-race in __mark_inode_dirty / generic_buffers_fsync

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __mark_inode_dirty / generic_buffers_fsync_noflush ext4				2	87d	98d	0/28	auto-obsoleted due to no activity on 2024/10/29 23:12
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BUG: KCSAN: data-race in __mark_inode_dirty / generic_buffers_fsync_noflush

write to 0xffff888117dbf7b8 of 4 bytes by task 4843 on cpu 0:
 __mark_inode_dirty+0x24e/0x7e0 fs/fs-writeback.c:2546
 generic_update_time fs/inode.c:2112 [inline]
 inode_update_time fs/inode.c:2125 [inline]
 touch_atime+0x230/0x350 fs/inode.c:2197
 file_accessed include/linux/fs.h:2539 [inline]
 filemap_splice_read+0x8a5/0x910 mm/filemap.c:2978
 ext4_file_splice_read+0x8f/0xb0 fs/ext4/file.c:158
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x269/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x398/0x660 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
 x64_sys_call+0xfbd/0x2dc0 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 0xffff888117dbf7b8 of 4 bytes by task 4834 on cpu 1:
 generic_buffers_fsync_noflush+0x83/0x120 fs/buffer.c:605
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ff/0x6c0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x116/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2904 [inline]
 ext4_buffered_write_iter+0x326/0x370 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf20
 iter_file_splice_write+0x5f1/0x980 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x160/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x302/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x398/0x660 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
 x64_sys_call+0xfbd/0x2dc0 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: 0x00000000 -> 0x00000028

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4834 Comm: syz.3.568 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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