KCSAN: data-race in __io_cqring_fill_event / io_req

KCSAN: data-race in __io_cqring_fill_event / io_req_defer
Status: moderation: reported on 2020/09/14 09:29
Reported-by: syzbot+7366b5fb4e738232bc93@syzkaller.appspotmail.com
First crash: 256d, last: 3d23h

Sample crash report:

==================================================================
BUG: KCSAN: data-race in __io_cqring_fill_event / io_req_defer

write to 0xffff88812b84e440 of 4 bytes by task 10605 on cpu 0:
 io_get_cqring fs/io_uring.c:1352 [inline]
 __io_cqring_fill_event+0x135/0x400 fs/io_uring.c:1491
 io_req_complete_post+0x49/0x570 fs/io_uring.c:1531
 __io_req_complete fs/io_uring.c:1579 [inline]
 __io_complete_rw+0x3a0/0x430 fs/io_uring.c:2522
 io_complete_rw+0x1b/0x20 fs/io_uring.c:2529
 io_rw_done fs/io_uring.c:2756 [inline]
 kiocb_done+0x1d3/0x8d0 fs/io_uring.c:2780
 io_write fs/io_uring.c:3453 [inline]
 io_issue_sqe+0x27c8/0x6080 fs/io_uring.c:6061
 io_wq_submit_work+0x112/0x300 fs/io_uring.c:6193
 io_worker_handle_work+0xbbb/0xe20 fs/io-wq.c:451
 io_wqe_worker+0x1e5/0x580 fs/io-wq.c:501
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff88812b84e440 of 4 bytes by task 10602 on cpu 1:
 req_need_defer fs/io_uring.c:1185 [inline]
 io_req_defer+0x344/0x470 fs/io_uring.c:5954
 io_queue_sqe+0x18/0x160 fs/io_uring.c:6361
 io_submit_sqe+0x15c7/0x30c0 fs/io_uring.c:6546
 io_submit_sqes+0x61f/0xaf0 fs/io_uring.c:6660
 __do_sys_io_uring_enter fs/io_uring.c:9240 [inline]
 __se_sys_io_uring_enter+0x217/0xb20 fs/io_uring.c:9182
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:9182
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10602 Comm: syz-executor.5 Tainted: G        W         5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (426):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/04/17 07:52	upstream	9cdbf646	7e2b734b	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/04/17 03:42	upstream	2f7b98d1	7e2b734b	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/03/25 05:53	upstream	4ee998b0	607e3baf	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/02/21 21:58	upstream	55f62bc8	a659b3f1	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/02/19 04:05	upstream	f40ddce8	14052202	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/02/10 02:14	upstream	e0756cfc	2bd9619f	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/02/03 21:29	upstream	3afe9076	624dad51	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/02/03 04:52	upstream	3aaf0a27	624dad51	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/02/02 05:00	upstream	88bb507a	e6b95f32	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/29 20:12	upstream	bec4c296	fc9fd31e	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/29 09:12	upstream	bec4c296	6593fd32	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/28 20:23	upstream	e5ff2cb9	7df34f59	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/28 18:58	upstream	76c057c8	7df34f59	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/28 06:49	upstream	76c057c8	eefc07f2	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/27 21:08	upstream	76c057c8	a57db36f	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/27 18:22	upstream	2ab38c17	a57db36f	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/27 07:35	upstream	2ab38c17	a0ebf917	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/26 17:03	upstream	13391c60	55a7d4df	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/26 14:44	upstream	13391c60	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/26 00:33	upstream	f8ad8187	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/25 09:39	upstream	6ee1d745	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/24 19:58	upstream	e6806137	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/24 01:06	upstream	e1ae4b0b	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/23 09:17	upstream	fe75a218	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/22 20:11	upstream	83d09ad4	52e37319	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/22 04:04	upstream	83d09ad4	d4f4eca5	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/21 14:24	upstream	9791581c	d4f4eca5	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/20 22:41	upstream	75439bc4	d4f4eca5	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/20 09:02	upstream	45dfb8a5	d4f4eca5	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/20 06:02	upstream	45dfb8a5	63631df1	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/18 22:35	upstream	1e2a199f	63631df1	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/18 14:18	upstream	19c329f6	63631df1	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/18 04:14	upstream	19c329f6	fd103621	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/17 15:27	upstream	0da0a8a0	fd103621	.config	log	report	info	KCSAN: data-race in __io_cqring_fill_event / io_req_defer
ci2-upstream-kcsan-gce	2021/01/17 11:15	upstream	0da0a8a0	813be542	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/17 09:56	upstream	0da0a8a0	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/16 21:01	upstream	54c6247d	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/16 07:12	upstream	1d94330a	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/15 17:46	upstream	5ee88057	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/15 04:13	upstream	14662050	65a7a854	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/14 23:10	upstream	14662050	468dbb55	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/14 15:33	upstream	65f0d241	468dbb55	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/14 00:32	upstream	65f0d241	269d24e8	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/13 22:26	upstream	65f0d241	a945f0a3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/13 11:33	upstream	e609571b	a945f0a3	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/12 18:50	upstream	e609571b	0cdd6185	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/11 23:42	upstream	a0d54b4f	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2021/01/11 10:52	upstream	7c53f6b6	2c1f2513	.config	log	report	info
ci2-upstream-kcsan-gce	2020/09/14 08:36	upstream	84b13499	2d3cdd63	.config	log	report
ci2-upstream-kcsan-gce	2020/09/14 03:07	upstream	84b13499	2d3cdd63	.config	log	report
ci2-upstream-kcsan-gce	2020/08/08 01:26	upstream	30185b69	ff51e522	.config	log	report