KCSAN: data-race in __writeback_single_inode / ext4_set

KCSAN: data-race in __writeback_single_inode / ext4_set_iomap (6)
Status: auto-closed as invalid on 2021/06/07 14:43
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 178d, last: 141d

similar bugs (5):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap (5)	1	308d	289d	0/22	auto-closed as invalid on 2020/12/22 22:18
upstream	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap (4)	6	345d	392d	0/22	auto-closed as invalid on 2020/11/16 08:39
upstream	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap (3)	1	457d	457d	0/22	auto-closed as invalid on 2020/07/26 23:43
upstream	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap (2)	3	469d	520d	0/22	closed as invalid on 2020/06/18 14:24
upstream	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap	1	627d	627d	0/22	auto-closed as invalid on 2020/03/14 05:26

Sample crash report:

==================================================================
BUG: KCSAN: data-race in __writeback_single_inode / ext4_set_iomap

write to 0xffff888105a78890 of 8 bytes by task 24316 on cpu 0:
 __writeback_single_inode+0x1e9/0x450 fs/fs-writeback.c:1503
 writeback_single_inode+0x177/0x590 fs/fs-writeback.c:1580
 sync_inode fs/fs-writeback.c:2624 [inline]
 sync_inode_metadata+0x57/0x80 fs/fs-writeback.c:2644
 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline]
 ext4_sync_file+0x359/0x670 fs/ext4/fsync.c:170
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2984 [inline]
 ext4_buffered_write_iter+0x39c/0x3f0 fs/ext4/file.c:277
 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519
 call_write_iter include/linux/fs.h:2116 [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+0x773/0xda0 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+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888105a78890 of 8 bytes by task 24300 on cpu 1:
 ext4_inode_datasync_dirty fs/ext4/inode.c:3330 [inline]
 ext4_set_iomap+0x17c/0x460 fs/ext4/inode.c:3345
 ext4_iomap_begin+0x5ce/0x620 fs/ext4/inode.c:3484
 iomap_apply+0x8d/0x400 fs/iomap/apply.c:46
 __iomap_dio_rw+0x5af/0xad0 fs/iomap/direct-io.c:561
 iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:649
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xa04/0x11d0 fs/ext4/file.c:678
 call_write_iter include/linux/fs.h:2116 [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+0x773/0xda0 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+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 24300 Comm: syz-executor.0 Tainted: G        W         5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/05/03 14:34	upstream	9ccce092fc64	ad61f371	.config	log	report	info	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap
ci2-upstream-kcsan-gce	2021/04/21 08:16	upstream	1fe5501ba1ab	95777977	.config	log	report	info	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap
ci2-upstream-kcsan-gce	2021/03/27 13:13	upstream	0f4498cef9f5	a8529b82	.config	log	report	info	KCSAN: data-race in __writeback_single_inode / ext4_set_iomap