KCSAN: data-race in do_writev / ksys

KCSAN: data-race in do_writev / ksys_write (2)

Status: auto-obsoleted due to no activity on 2023/03/05 03:08
Subsystems: fs
[Documentation on labels]
First crash: 1071d, last: 1071d

▶ ▼ Similar bugs (1)

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in do_writev / ksys_write fs	6				1	2258d	2258d	0/29	closed as invalid on 2019/11/19 13:44

Sample crash report:

==================================================================
BUG: KCSAN: data-race in do_writev / ksys_write

write to 0xffff88810472a668 of 8 bytes by task 20232 on cpu 0:
 do_writev+0x351/0x4b0 fs/read_write.c:979
 __do_sys_writev fs/read_write.c:1050 [inline]
 __se_sys_writev fs/read_write.c:1047 [inline]
 __x64_sys_writev+0x41/0x50 fs/read_write.c:1047
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

write to 0xffff88810472a668 of 8 bytes by task 20231 on cpu 1:
 ksys_write+0x11b/0x1a0 fs/read_write.c:639
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x000000000000046c -> 0x0000000000000564

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 20231 Comm: syz-executor.1 Not tainted 6.2.0-rc4-syzkaller-00379-gf883675bf652-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
==================================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2023/01/22 02:47	upstream	f883675bf652	cc0f9968	.config	console log	report			info		ci2-upstream-kcsan-gce	KCSAN: data-race in do_writev / ksys_write

* ~~Struck through~~ repros no longer work on HEAD.