KCSAN: data-race in __mark_inode_dirty / ext4_sync

KCSAN: data-race in __mark_inode_dirty / ext4_sync_file (5)
Status: auto-closed as invalid on 2021/04/23 13:27
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 132d, last: 132d

similar bugs (4):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __mark_inode_dirty / ext4_sync_file (3)	4	275d	316d	0/22	auto-closed as invalid on 2020/12/01 12:40
upstream	KCSAN: data-race in __mark_inode_dirty / ext4_sync_file	1	432d	432d	0/22	closed as invalid on 2020/06/18 14:13
upstream	KCSAN: data-race in __mark_inode_dirty / ext4_sync_file (2)	1	372d	372d	0/22	auto-closed as invalid on 2020/08/27 02:47
upstream	KCSAN: data-race in __mark_inode_dirty / ext4_sync_file (4)	5	172d	233d	0/22	auto-closed as invalid on 2021/03/14 09:37

Sample crash report:

==================================================================
BUG: KCSAN: data-race in __mark_inode_dirty / ext4_sync_file

write to 0xffff8880135ef738 of 8 bytes by task 10107 on cpu 0:
 __mark_inode_dirty+0x222/0x6f0 fs/fs-writeback.c:2312
 mark_inode_dirty include/linux/fs.h:2267 [inline]
 generic_write_end+0x166/0x240 fs/buffer.c:2203
 ext4_da_write_end+0x59b/0x760 fs/ext4/inode.c:3112
 generic_perform_write+0x23e/0x3a0 mm/filemap.c:3586
 ext4_buffered_write_iter+0x2e5/0x3e0 fs/ext4/file.c:269
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8880135ef738 of 8 bytes by task 10117 on cpu 1:
 ext4_fsync_nojournal fs/ext4/fsync.c:87 [inline]
 ext4_sync_file+0x294/0x6e0 fs/ext4/fsync.c:170
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2843 [inline]
 ext4_buffered_write_iter+0x38f/0x3e0 fs/ext4/file.c:277
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10117 Comm: syz-executor.3 Not tainted 5.12.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci2-upstream-kcsan-gce	2021/03/19 13:17	upstream	8b12a62a4e3e	2af9d324	.config	log	report			info	KCSAN: data-race in __mark_inode_dirty / ext4_sync_file