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: 411d, last: 12h11m

Sample crash report:

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

write to 0xffffffff85a932d0 of 8 bytes by task 1177 on cpu 0:
 prb_reserve+0x799/0xbf0
 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2176
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2229
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2256
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2266
 dump_stack_print_info+0xba/0x130 lib/dump_stack.c:57
 __dump_stack lib/dump_stack.c:87 [inline]
 dump_stack_lvl+0xca/0x122 lib/dump_stack.c:106
 dump_stack+0x11/0x1b lib/dump_stack.c:113
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail+0x23c/0x250 lib/fault-inject.c:146
 should_fail_usercopy+0x16/0x20 lib/fault-inject-usercopy.c:37
 _copy_from_user+0x1c/0xd0 lib/usercopy.c:14
 copy_from_user include/linux/uaccess.h:192 [inline]
 __copy_msghdr_from_user net/socket.c:2291 [inline]
 copy_msghdr_from_user net/socket.c:2342 [inline]
 sendmsg_copy_msghdr+0x60/0x2a0 net/socket.c:2440
 ___sys_sendmsg net/socket.c:2459 [inline]
 __sys_sendmsg+0x166/0x230 net/socket.c:2492
 __do_sys_sendmsg net/socket.c:2501 [inline]
 __se_sys_sendmsg net/socket.c:2499 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2499
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff85a932d0 of 8 bytes by task 1169 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+0x2e3/0x950 kernel/printk/printk_ringbuffer.c:1881
 prb_read_valid+0x39/0x60 kernel/printk/printk_ringbuffer.c:1929
 console_unlock+0x203/0xb60 kernel/printk/printk.c:2654
 do_con_write+0x5ed7/0x5f40
 con_write+0x20/0x40 drivers/tty/vt/vt.c:3295
 process_output_block drivers/tty/n_tty.c:592 [inline]
 n_tty_write+0x77b/0xaf0 drivers/tty/n_tty.c:2288
 do_tty_write drivers/tty/tty_io.c:1038 [inline]
 file_tty_write+0x409/0x660 drivers/tty/tty_io.c:1110
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1131
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x7f5/0x950 fs/read_write.c:590
 ksys_write+0xd9/0x190 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000000021bc -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1169 Comm: syz-executor.1 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (911):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/11/29 16:01	upstream	d58071a8a76d	d0830353	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/29 11:29	upstream	d58071a8a76d	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/28 22:16	upstream	d06c942efea4	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/28 08:50	upstream	3498e7f2bb41	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/27 22:37	upstream	741392771338	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/26 23:07	upstream	c5c17547b778	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/26 09:22	upstream	a4849f6000e2	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/25 19:30	upstream	b501b85957de	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/25 17:59	upstream	5f53fa508db0	63eeac02	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/24 20:32	upstream	5f53fa508db0	545ab074	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/24 00:04	upstream	5d9f4cf36721	545ab074	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/22 14:03	upstream	136057256686	545ab074	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/22 12:38	upstream	136057256686	4eb20a4e	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/22 03:36	upstream	40c93d7fff6f	4eb20a4e	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/21 10:51	upstream	923dcc5eb0c1	4eb20a4e	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/20 21:23	upstream	61564e7b3abc	4eb20a4e	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/20 03:51	upstream	a90af8f15bdc	4eb20a4e	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/19 14:47	upstream	4c388a8e740d	3a9d0024	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/19 11:35	upstream	4c388a8e740d	31a30fc0	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/18 22:17	upstream	6fdf886424cf	31a30fc0	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/18 15:04	upstream	42eb8fdac2fc	31a30fc0	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/18 07:03	upstream	42eb8fdac2fc	cafff8b6	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/17 18:45	upstream	ee1703cda8dc	cafff8b6	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/16 23:01	upstream	8ab774587903	cafff8b6	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/16 13:01	upstream	8ab774587903	600426bd	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/15 12:25	upstream	8ab774587903	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/14 22:34	upstream	ce49bfc8d037	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/14 09:30	upstream	c8c109546a19	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/13 19:50	upstream	a9b9669d9822	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/13 02:39	upstream	66f4beaa6c1d	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/12 14:08	upstream	5833291ab6de	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/12 00:43	upstream	ca2ef2d9f2aa	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/11 08:27	upstream	debe436e77c7	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/10 19:28	upstream	89d714ab6043	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/10 14:28	upstream	cb690f5238d7	75b04091	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/10 02:04	upstream	cb690f5238d7	55fa030c	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/09 14:53	upstream	d2f38a3c6507	59bcaf9a	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/09 00:25	upstream	e851dfae4371	8ab17e57	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/08 19:19	upstream	e851dfae4371	d29682f1	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/08 12:07	upstream	6b75d88fa81b	d29682f1	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/08 00:50	upstream	6b75d88fa81b	4c1be0be	.config	log	report	info	KCSAN: data-race in _prb_read_valid / prb_reserve
ci2-upstream-kcsan-gce	2021/11/07 11:24	upstream	b5013d084e03	4c1be0be	.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