KCSAN: data-race in ext4_sync_file / writeback_single

KCSAN: data-race in ext4_sync_file / writeback_single_inode (2)
Status: moderation: reported on 2020/09/24 09:26
Reported-by: syzbot+7e1bab882548e4db2a89@syzkaller.appspotmail.com
First crash: 399d, last: 16h32m

similar bugs (1):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in ext4_sync_file / writeback_single_inode				31	407d	592d	0/22	closed as invalid on 2020/06/18 14:24

Sample crash report:

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

write to 0xffff888106a42af8 of 8 bytes by task 6880 on cpu 0:
 writeback_single_inode+0x148/0x3c0 fs/fs-writeback.c:1723
 sync_inode fs/fs-writeback.c:2745 [inline]
 sync_inode_metadata+0x57/0x80 fs/fs-writeback.c:2765
 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:2987 [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:2114 [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:1319 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1311
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888106a42af8 of 8 bytes by task 6885 on cpu 1:
 ext4_fsync_nojournal fs/ext4/fsync.c:87 [inline]
 ext4_sync_file+0x294/0x670 fs/ext4/fsync.c:170
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2987 [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:2114 [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_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000007 -> 0x0000000000000080

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6885 Comm: syz-executor.1 Not tainted 5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (231):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/07/28 20:12	upstream	4010a528219e	9a4781d4	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/07/26 03:10	upstream	ff1176468d36	4d1b57d4	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/07/22 14:02	upstream	3d5895cd3517	241790bb	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/07/21 20:52	upstream	7b6ae471e541	29c3f20f	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/07/09 21:05	upstream	3dbdb38e2869	8f5a7b8c	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/07/08 14:58	upstream	3dbdb38e2869	1aade754	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/07/05 18:33	upstream	3dbdb38e2869	55aa55c2	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/06/27 13:31	upstream	625acffd7ae2	9d2ab5df	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/06/16 11:55	upstream	94f0b2d4a1d0	c06f97ad	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/06/15 14:10	upstream	009c9aa5be65	8022d7e3	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/06/11 16:06	upstream	06af8679449d	1ba81399	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/06/03 05:31	upstream	324c92e5e0ee	0740de69	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/31 18:33	upstream	c2131f7e73c9	032639db	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/26 00:11	upstream	a050a6d2b7e8	93d3a9f6	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/23 21:40	upstream	4d7620341eda	3c7fef33	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/21 14:55	upstream	79a106fc6585	3c7fef33	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/19 02:01	upstream	8ac91e6c6033	a343ba6b	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/16 09:25	upstream	c12a29ed9094	f54a5c09	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/15 00:16	upstream	bd3c9cdb21a2	8bdd5343	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/11 21:57	upstream	88b06399c9c7	b3c3bb8e	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/11 15:46	upstream	1140ab592e2e	ca873091	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/10 10:02	upstream	6efb943b8616	bc5434be	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/08 11:29	upstream	dd860052c99b	bc5434be	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/07 21:34	upstream	1ad77a05cfae	bc5434be	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/07 10:46	upstream	e48661230cc3	f6da8120	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/06 01:08	upstream	a79cdfba68a1	06c27ff5	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/05 09:57	upstream	d665ea6ea86c	06c27ff5	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/03 22:00	upstream	6f8ee8d36d07	ad61f371	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/03 16:04	upstream	9ccce092fc64	ad61f371	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/05/02 12:58	upstream	17ae69aba89d	77e2b668	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/30 14:05	upstream	8ca5297e7e38	77e2b668	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/28 19:12	upstream	e359bce39d90	77e2b668	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/28 01:52	upstream	e359bce39d90	805b5003	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/27 10:56	upstream	4a0225c3d208	805b5003	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/26 23:07	upstream	9f4ad9e425a1	8ee2dea6	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/25 19:28	upstream	d2d09fbe33f8	2a82f1b3	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/24 14:42	upstream	8db5efb83fa9	17f0b706	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/23 06:19	upstream	90c911ad7445	590921a5	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/22 12:07	upstream	16fc44d6387e	33c28d03	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/21 20:08	upstream	16fc44d6387e	2bc8999a	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/21 18:31	upstream	16fc44d6387e	95777977	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/04/21 00:45	upstream	1fe5501ba1ab	c0ced557	.config	log	report	info	KCSAN: data-race in ext4_sync_file / writeback_single_inode
ci2-upstream-kcsan-gce	2021/01/16 09:26	upstream	1d94330a437a	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/22 11:25	upstream	98477740630f	3e8f6c27	.config	log	report	info
ci2-upstream-kcsan-gce	2020/06/25 07:05	upstream	26e122e97a3d	9d60b18e	.config	log	report