KCSAN: data-race in _prb_read_valid / prb

KCSAN: data-race in _prb_read_valid / prb_reserve
Status: moderation: reported on 2020/11/09 13:24
Reported-by: syzbot+615128043c250cbd858b@syzkaller.appspotmail.com
First crash: 286d, last: 14h56m

Sample crash report:

==================================================================
BUG: KCSAN: data-race in _prb_read_valid / prb_reserve

write to 0xffffffff836f5848 of 8 bytes by task 5232 on cpu 0:
 prb_reserve+0x769/0xbc0 kernel/printk/printk_ringbuffer.c:1538
 vprintk_store+0x3e9/0x9c0 kernel/printk/printk.c:2105
 vprintk_emit+0xca/0x3d0 kernel/printk/printk.c:2157
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2185
 vprintk+0x15a/0x170 kernel/printk/printk_safe.c:392
 printk+0x62/0x87 kernel/printk/printk.c:2216
 blk_add_partitions block/partitions/core.c:644 [inline]
 bdev_disk_changed+0xce1/0xea0 block/partitions/core.c:697
 loop_reread_partitions drivers/block/loop.c:652 [inline]
 loop_set_status+0x4dc/0x5a0 drivers/block/loop.c:1510
 lo_ioctl+0x764/0x1210 drivers/block/loop.c:1620
 blkdev_ioctl+0x1d0/0x3c0 block/ioctl.c:585
 block_ioctl+0x6d/0x80 fs/block_dev.c:1602
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xcb/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

read to 0xffffffff836f5848 of 8 bytes by task 5221 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:480 [inline]
 prb_first_seq kernel/printk/printk_ringbuffer.c:1835 [inline]
 _prb_read_valid+0x753/0x8d0 kernel/printk/printk_ringbuffer.c:1881
 prb_read_valid+0x39/0x60 kernel/printk/printk_ringbuffer.c:1929
 console_unlock+0xa06/0xb30 kernel/printk/printk.c:2667
 vprintk_emit+0x125/0x3d0 kernel/printk/printk.c:2174
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2185
 vprintk+0x15a/0x170 kernel/printk/printk_safe.c:392
 printk+0x62/0x87 kernel/printk/printk.c:2216
 blk_add_partition block/partitions/core.c:564 [inline]
 blk_add_partitions block/partitions/core.c:655 [inline]
 bdev_disk_changed+0x97f/0xea0 block/partitions/core.c:697
 loop_reread_partitions drivers/block/loop.c:652 [inline]
 loop_set_status+0x4dc/0x5a0 drivers/block/loop.c:1510
 lo_ioctl+0x764/0x1210 drivers/block/loop.c:1620
 blkdev_ioctl+0x1d0/0x3c0 block/ioctl.c:585
 block_ioctl+0x6d/0x80 fs/block_dev.c:1602
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xcb/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: 0x0000000000003543 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5221 Comm: syz-executor.5 Not tainted 5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (619):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/07/27 23:50	upstream	7d549995d4e0	17d6ab15	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/27 17:18	upstream	ff1176468d36	17d6ab15	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/26 08:09	upstream	ff1176468d36	fd511809	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/26 05:02	upstream	ff1176468d36	4d1b57d4	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/25 17:03	upstream	d8079fac1681	4d1b57d4	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/25 00:59	upstream	7ffca2bb9d8b	4d1b57d4	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/24 12:39	upstream	f0fddcec6b62	4d1b57d4	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/24 05:30	upstream	f0fddcec6b62	bc5f1d88	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/23 14:58	upstream	8baef6386baa	bc5f1d88	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/23 03:30	upstream	9bead1b58c4c	bc5f1d88	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/22 13:16	upstream	3d5895cd3517	241790bb	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/21 21:49	upstream	7b6ae471e541	29c3f20f	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/21 14:54	upstream	8cae8cd89f05	29c3f20f	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/20 15:17	upstream	8cae8cd89f05	1b201b48	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/20 00:13	upstream	2734d6c1b1a0	bc48c9ab	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/19 13:28	upstream	2734d6c1b1a0	e6a17580	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/18 22:00	upstream	f0eb870a8422	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/18 05:56	upstream	1d67c8d993ba	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/17 14:40	upstream	d980cc0620ae	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/17 00:04	upstream	0d18c12b288a	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/16 11:31	upstream	d936eb238744	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/15 21:22	upstream	dd9c7df94c1b	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/15 17:04	upstream	8096acd7442e	f115ae98	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/15 01:23	upstream	8096acd7442e	b9a2f64e	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/14 20:04	upstream	8096acd7442e	94e0b707	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/14 15:19	upstream	40226a3d96ef	94e0b707	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/14 01:58	upstream	40226a3d96ef	484502bd	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/13 22:27	upstream	40226a3d96ef	70168d5c	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/13 14:36	upstream	7fef2edf7cc7	70168d5c	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/12 22:26	upstream	7fef2edf7cc7	f415556d	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/12 19:18	upstream	e73f0f0ee754	f415556d	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/12 08:04	upstream	e73f0f0ee754	a4869c92	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/11 21:45	upstream	98f7fdced2e0	8f5a7b8c	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/09 23:18	upstream	3dbdb38e2869	8f5a7b8c	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/09 22:54	upstream	3dbdb38e2869	8f5a7b8c	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/09 11:07	upstream	3dbdb38e2869	281e815f	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/08 20:40	upstream	3dbdb38e2869	1b20171a	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/08 11:37	upstream	3dbdb38e2869	1aade754	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/07 22:11	upstream	3dbdb38e2869	95793bce	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/07 11:05	upstream	3dbdb38e2869	4846d5c1	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/06 21:10	upstream	3dbdb38e2869	cca78469	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/06 08:27	upstream	3dbdb38e2869	6c4484eb	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/02 19:50	upstream	3dbdb38e2869	55aa55c2	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/02 16:01	upstream	3dbdb38e2869	658ebc66	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/02 00:51	upstream	e058a84bfddc	658ebc66	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/07/01 11:12	upstream	dbe69e433722	658ebc66	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/06/30 23:39	upstream	df04fbe8680b	38a885d1	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/06/30 11:00	upstream	007b350a5875	84fd4c77	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/06/29 20:20	upstream	c54b245d0118	a4fccb01	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/01/17 12:41	upstream	0da0a8a0a0e1	813be542	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/09 09:54	upstream	f8394f232b1e	cba33199	.config	log	report	info
ci2-upstream-kcsan-gce	2020/11/07 20:52	upstream	659caaf65dc9	cba33199	.config	log	report	info
ci2-upstream-kcsan-gce	2020/10/14 17:14	upstream	b5fc7a89e58b	fc7735a2	.config	log	report	info