syzbot


KCSAN: data-race in fsnotify_perm / setattr_copy (3)

Status: auto-closed as invalid on 2022/02/23 05:39
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 378d, last: 378d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in fsnotify_perm / setattr_copy 1 569d 569d 0/24 auto-closed as invalid on 2021/08/17 01:02
upstream KCSAN: data-race in fsnotify_perm / setattr_copy (2) 1 505d 505d 0/24 auto-closed as invalid on 2021/10/19 09:08

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

write to 0xffff888134155928 of 2 bytes by task 21 on cpu 1:
 setattr_copy+0x238/0x250 fs/attr.c:247
 shmem_setattr+0xb0/0x450 mm/shmem.c:1111
 notify_change+0x924/0xbf0 fs/attr.c:410
 handle_remove drivers/base/devtmpfs.c:346 [inline]
 handle drivers/base/devtmpfs.c:395 [inline]
 devtmpfs_work_loop+0x845/0x930 drivers/base/devtmpfs.c:408
 devtmpfsd+0x3f/0x40 drivers/base/devtmpfs.c:450
 kthread+0x1bf/0x1e0 kernel/kthread.c:359
 ret_from_fork+0x1f/0x30

read to 0xffff888134155928 of 2 bytes by task 1820 on cpu 0:
 fsnotify_parent include/linux/fsnotify.h:65 [inline]
 fsnotify_file include/linux/fsnotify.h:99 [inline]
 fsnotify_perm+0x296/0x370 include/linux/fsnotify.h:124
 security_file_open+0x85/0x90 security/security.c:1631
 do_dentry_open+0x232/0x860 fs/open.c:811
 vfs_open+0x43/0x50 fs/open.c:959
 do_open fs/namei.c:3426 [inline]
 path_openat+0x170c/0x1f30 fs/namei.c:3559
 do_filp_open+0x105/0x220 fs/namei.c:3586
 do_sys_openat2+0xb5/0x2b0 fs/open.c:1214
 do_sys_open fs/open.c:1230 [inline]
 __do_sys_openat fs/open.c:1246 [inline]
 __se_sys_openat fs/open.c:1241 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1241
 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: 0x61b0 -> 0x6000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1820 Comm: syz-executor.0 Not tainted 5.16.0-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 Assets Title
ci2-upstream-kcsan-gce 2022/01/19 05:33 upstream 99613159ad74 731a2d23 .config console log report info KCSAN: data-race in fsnotify_perm / setattr_copy
* Struck through repros no longer work on HEAD.