KCSAN: data-race in dev_uevent / really

KCSAN: data-race in dev_uevent / really_probe
Status: auto-closed as invalid on 2020/06/18 13:13
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 506d, last: 506d

similar bugs (3):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in dev_uevent / really_probe (2)	3	426d	439d	0/22	auto-closed as invalid on 2020/09/01 14:47
upstream	KCSAN: data-race in dev_uevent / really_probe (4)	5	182d	238d	0/22	auto-closed as invalid on 2021/05/17 10:55
upstream	KCSAN: data-race in dev_uevent / really_probe (3)	13	277d	294d	0/22	auto-closed as invalid on 2021/01/28 09:10

Sample crash report:

==================================================================
BUG: KCSAN: data-race in dev_uevent / really_probe

write to 0xffff88809f312908 of 8 bytes by task 4146 on cpu 1:
 really_probe+0x117/0x490 drivers/base/dd.c:501
 driver_probe_device+0xb3/0x160 drivers/base/dd.c:701
 __device_attach_driver+0x134/0x160 drivers/base/dd.c:808
 bus_for_each_drv+0xe4/0x130 drivers/base/bus.c:431
 __device_attach+0x18f/0x260 drivers/base/dd.c:874
 device_initial_probe+0x20/0x30 drivers/base/dd.c:921
 bus_probe_device+0x130/0x160 drivers/base/bus.c:491
 device_add+0xd96/0x10b0 drivers/base/core.c:2533
 usb_new_device.cold+0x21d/0x775 drivers/usb/core/hub.c:2548
 hub_port_connect drivers/usb/core/hub.c:5195 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
 port_event drivers/usb/core/hub.c:5481 [inline]
 hub_event+0x18d5/0x2710 drivers/usb/core/hub.c:5563
 process_one_work+0x424/0x930 kernel/workqueue.c:2268
 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2414
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff88809f312908 of 8 bytes by task 5269 on cpu 0:
 dev_uevent+0xb2/0x380 drivers/base/core.c:1466
 uevent_show+0x11b/0x1f0 drivers/base/core.c:1538
 dev_attr_show+0x46/0x90 drivers/base/core.c:1242
 sysfs_kf_seq_show+0x15e/0x290 fs/sysfs/file.c:60
 kernfs_seq_show+0xa8/0xe0 fs/kernfs/file.c:167
 seq_read+0x2ef/0x940 fs/seq_file.c:206
 kernfs_fop_read+0x9e/0x350 fs/kernfs/file.c:251
 __vfs_read+0x58/0xb0 fs/read_write.c:426
 vfs_read fs/read_write.c:462 [inline]
 vfs_read+0x13e/0x2b0 fs/read_write.c:447
 ksys_read+0xc5/0x1a0 fs/read_write.c:588
 __do_sys_read fs/read_write.c:598 [inline]
 __se_sys_read fs/read_write.c:596 [inline]
 __x64_sys_read+0x49/0x60 fs/read_write.c:596
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5269 Comm: systemd-journal Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci2-upstream-kcsan-gce	2020/05/08 20:31	https://github.com/google/ktsan.git kcsan	7c3cd68e5d38	fe4122c3	.config	log	report