syzbot


KCSAN: data-race in __tty_hangup / do_dentry_open (4)

Status: auto-obsoleted due to no activity on 2024/03/04 05:22
Subsystems: serial
[Documentation on labels]
Reported-by: syzbot+7e8e098ebb940693c013@syzkaller.appspotmail.com
First crash: 80d, last: 80d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __tty_hangup / do_dentry_open serial 1 1177d 1177d 0/26 auto-closed as invalid on 2021/03/02 15:38
upstream KCSAN: data-race in __tty_hangup / do_dentry_open (2) serial 1 677d 677d 0/26 auto-closed as invalid on 2022/07/16 05:33
upstream KCSAN: data-race in __tty_hangup / do_dentry_open (3) serial 1 593d 593d 0/26 auto-obsoleted due to no activity on 2022/10/07 18:15

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __tty_hangup / do_dentry_open

write to 0xffff88813492d5b0 of 8 bytes by task 7152 on cpu 0:
 __tty_hangup+0x1e8/0x530 drivers/tty/tty_io.c:621
 tty_vhangup drivers/tty/tty_io.c:700 [inline]
 tty_ioctl+0x60a/0xbc0 drivers/tty/tty_io.c:2743
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff88813492d5b0 of 8 bytes by task 7148 on cpu 1:
 do_dentry_open+0x6ad/0xbd0 fs/open.c:959
 vfs_open+0x4a/0x50 fs/open.c:1087
 do_open fs/namei.c:3641 [inline]
 path_openat+0x1819/0x1d30 fs/namei.c:3798
 do_filp_open+0xf6/0x200 fs/namei.c:3825
 do_sys_openat2+0xab/0x110 fs/open.c:1404
 do_sys_open fs/open.c:1419 [inline]
 __do_sys_openat fs/open.c:1435 [inline]
 __se_sys_openat fs/open.c:1430 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1430
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0xffffffff850974a8 -> 0xffffffff85097340

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7148 Comm: syz-executor.4 Not tainted 6.8.0-rc1-syzkaller-00385-g4854cf9c61d0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/29 05:21 upstream 4854cf9c61d0 cc4a4020 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __tty_hangup / do_dentry_open
* Struck through repros no longer work on HEAD.