KCSAN: data-race in ext4_write_end / mpage_process_page

KCSAN: data-race in ext4_write_end / mpage_process_page_bufs (3)
Status: moderation: reported on 2020/12/06 12:03
Reported-by: syzbot+7267bfaa83b92bf97546@syzkaller.appspotmail.com
First crash: 403d, last: 1d06h

similar bugs (2):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs				1	583d	583d	0/22	auto-closed as invalid on 2020/03/01 21:02
upstream	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs (2)				6	422d	493d	0/22	closed as invalid on 2020/06/18 14:24

Sample crash report:

==================================================================
BUG: KCSAN: data-race in ext4_write_end / mpage_process_page_bufs

write to 0xffff8881350cb740 of 8 bytes by task 25815 on cpu 0:
 i_size_write include/linux/fs.h:871 [inline]
 ext4_update_inode_size fs/ext4/ext4.h:3359 [inline]
 ext4_write_end+0x1d7/0x820 fs/ext4/inode.c:1309
 generic_perform_write+0x22a/0x3c0 mm/filemap.c:3667
 ext4_buffered_write_iter+0x2f2/0x3f0 fs/ext4/file.c:269
 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519
 call_write_iter include/linux/fs.h:2114 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x69d/0x770 fs/read_write.c:605
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 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 0xffff8881350cb740 of 8 bytes by task 25825 on cpu 1:
 i_size_read include/linux/fs.h:849 [inline]
 mpage_submit_page fs/ext4/inode.c:2094 [inline]
 mpage_process_page_bufs+0x3f3/0x560 fs/ext4/inode.c:2214
 mpage_prepare_extent_to_map+0x4e6/0x640 fs/ext4/inode.c:2626
 ext4_writepages+0x6c6/0x1d10 fs/ext4/inode.c:2754
 do_writepages+0x7b/0x150 mm/page-writeback.c:2355
 __filemap_fdatawrite_range mm/filemap.c:413 [inline]
 filemap_write_and_wait_range+0x20a/0x390 mm/filemap.c:686
 filemap_write_and_wait include/linux/fs.h:2897 [inline]
 iomap_bmap+0x68/0x110 fs/iomap/fiemap.c:130
 ext4_bmap+0x213/0x230 fs/ext4/inode.c:3233
 bmap+0x56/0x80 fs/inode.c:1711
 ioctl_fibmap fs/ioctl.c:77 [inline]
 file_ioctl fs/ioctl.c:534 [inline]
 do_vfs_ioctl+0x1284/0x1410 fs/ioctl.c:1048
 __do_sys_ioctl fs/ioctl.c:1067 [inline]
 __se_sys_ioctl+0x83/0x140 fs/ioctl.c:1055
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055
 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: 0x00000000000dd000 -> 0x00000000000de000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 25825 Comm: syz-executor.1 Tainted: G        W         5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (108):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/07/27 07:57	upstream	ff1176468d36	fd511809	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/07/23 11:00	upstream	9bead1b58c4c	bc5f1d88	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/07/22 10:12	upstream	3d5895cd3517	29c3f20f	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/07/20 16:33	upstream	8cae8cd89f05	1b201b48	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/07/02 18:24	upstream	3dbdb38e2869	55aa55c2	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/28 23:26	upstream	62fb9874f5da	9d2ab5df	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/27 19:15	upstream	625acffd7ae2	9d2ab5df	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/26 00:13	upstream	44db63d1ad8d	ae6bf8dd	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/22 02:27	upstream	a96bfed64c89	aba2b2fb	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/20 18:43	upstream	cba5e97280f5	aba2b2fb	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/18 20:25	upstream	b1edae0d5f2e	aba2b2fb	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/18 19:07	upstream	fd0aa1a4567d	aba2b2fb	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/17 05:56	upstream	6b00bc639f1f	aba2b2fb	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/12 03:19	upstream	f21b807c3cf8	1ba81399	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/10 03:15	upstream	cd1245d75ce9	1ba81399	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/05 15:16	upstream	9d32fa5d74b1	500c2339	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/03 09:06	upstream	324c92e5e0ee	0740de69	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/06/01 15:17	upstream	c2131f7e73c9	032639db	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/29 08:48	upstream	6799d4f2da49	858ea628	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/29 03:29	upstream	5ff2756afde0	858ea628	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/25 05:02	upstream	1434a3127887	3c7fef33	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/21 00:14	upstream	f01da525b3de	3c7fef33	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/13 23:00	upstream	c06a2ba62fc4	ecb594cb	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/10 05:04	upstream	9819f682e48c	bc5434be	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/05 00:11	upstream	5e321ded302d	06c27ff5	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/05/03 00:36	upstream	17ae69aba89d	77e2b668	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/27 15:24	upstream	4a0225c3d208	805b5003	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/24 05:45	upstream	8db5efb83fa9	17f0b706	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/23 00:37	upstream	90c911ad7445	590921a5	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/22 11:58	upstream	16fc44d6387e	33c28d03	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/20 05:37	upstream	7af08140979a	4285c989	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/19 13:02	upstream	bf05bf16c76b	50f523d7	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/16 18:43	upstream	2f7b98d1e55c	7e2b734b	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/15 17:46	upstream	7f75285ca572	c59079a6	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/15 01:28	upstream	7f75285ca572	fcdb12ba	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/13 23:07	upstream	eebe426d32e1	a184b83e	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/12 23:50	upstream	89698becf06d	6a81331a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/10 02:26	upstream	4e04e7513b0f	6a81331a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/09 13:13	upstream	17e7124aad76	6a81331a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/08 09:48	upstream	454859c552da	6a81331a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/04/04 03:35	upstream	2023a53bdf41	6a81331a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/03/29 22:03	upstream	1e43c377a79f	6a81331a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/03/29 11:54	upstream	a5e13c6df0e4	a8529b82	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/03/23 21:13	upstream	7acac4b3196c	e613994b	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/03/21 01:14	upstream	812da4d39463	17810eae	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/03/14 23:58	upstream	75013c6c52d8	cc1cff8f	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/03/13 00:33	upstream	f296bfd5cd04	429d8a6b	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/02/19 15:48	upstream	f40ddce88593	f689d40a	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/02/19 00:47	upstream	f40ddce88593	14052202	.config	log	report	info	KCSAN: data-race in ext4_write_end / mpage_process_page_bufs
ci2-upstream-kcsan-gce	2021/01/17 07:34	upstream	54c6247d06f1	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/03 19:14	upstream	34816d20f173	59ad4022	.config	log	report	info
ci2-upstream-kcsan-gce	2020/06/20 12:49	upstream	672f9255a727	c655ec77	.config	log	report