syzbot


KCSAN: data-race in may_open / setattr_copy

Status: auto-closed as invalid on 2021/11/01 17:23
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 434d, last: 434d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in may_open / setattr_copy (2) 1 332d 332d 0/24 auto-closed as invalid on 2022/02/12 13:06

Sample crash report:
==================================================================
BUG: KCSAN: data-race in may_open / setattr_copy

write to 0xffff888106e7c348 of 2 bytes by task 19 on cpu 1:
 setattr_copy+0x1af/0x1c0 fs/attr.c:247
 shmem_setattr+0xb0/0x450 mm/shmem.c:1126
 notify_change+0x8a3/0xac0 fs/attr.c:410
 handle_remove drivers/base/devtmpfs.c:333 [inline]
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop+0x81c/0x960 drivers/base/devtmpfs.c:395
 devtmpfsd+0x3f/0x40 drivers/base/devtmpfs.c:437
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30

read to 0xffff888106e7c348 of 2 bytes by task 18590 on cpu 0:
 may_open+0x42/0x2f0 fs/namei.c:3025
 do_open fs/namei.c:3426 [inline]
 path_openat+0x1733/0x1ec0 fs/namei.c:3561
 do_filp_open+0x105/0x220 fs/namei.c:3588
 do_sys_openat2+0xb5/0x2b0 fs/open.c:1200
 do_sys_open fs/open.c:1216 [inline]
 __do_sys_open fs/open.c:1224 [inline]
 __se_sys_open fs/open.c:1220 [inline]
 __x64_sys_open+0xe2/0x110 fs/open.c:1220
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x6180 -> 0x6000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18590 Comm: systemd-udevd Not tainted 5.15.0-rc3-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 2021/09/27 17:17 upstream 5816b3e6577e 78494d16 .config log report info KCSAN: data-race in may_open / setattr_copy
* Struck through repros no longer work on HEAD.