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KCSAN: data-race in __fsnotify_parent / fsnotify_detach_connector_from_object

Status: closed as invalid on 2019/11/19 15:04
Subsystems: fs
[Documentation on labels]
First crash: 1623d, last: 1623d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __fsnotify_parent / fsnotify_detach_connector_from_object (2) fs 6 1475d 1615d 0/26 auto-closed as invalid on 2020/06/16 20:23
upstream KCSAN: data-race in __fsnotify_parent / fsnotify_detach_connector_from_object (3) fs syz 975 1d16h 136d 0/26 moderation: reported syz repro on 2023/12/08 00:00

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __fsnotify_parent / fsnotify_detach_connector_from_object

read to 0xffff88812512481c of 4 bytes by task 29333 on cpu 0:
 __fsnotify_parent+0xc7/0x230 fs/notify/fsnotify.c:157
 fsnotify_parent include/linux/fsnotify.h:40 [inline]
 fsnotify_path include/linux/fsnotify.h:50 [inline]
 fsnotify_perm include/linux/fsnotify.h:85 [inline]
 security_file_permission+0x194/0x280 security/security.c:1379
 rw_verify_area+0xe1/0x250 fs/read_write.c:399
 do_splice_to+0x6c/0x130 fs/splice.c:865
 splice_direct_to_actor+0x1a1/0x510 fs/splice.c:954
 do_splice_direct+0x161/0x1e0 fs/splice.c:1063
 do_sendfile+0x384/0x7f0 fs/read_write.c:1464
 __do_sys_sendfile64 fs/read_write.c:1519 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0xbe/0x140 fs/read_write.c:1511
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff88812512481c of 4 bytes by task 29332 on cpu 1:
 fsnotify_detach_connector_from_object+0xb8/0x210 fs/notify/mark.c:184
 fsnotify_put_mark+0x2e9/0x3b0 fs/notify/mark.c:250
 fsnotify_clear_marks_by_group+0x2b1/0x320 fs/notify/mark.c:760
 fsnotify_destroy_group+0x66/0x190 fs/notify/group.c:60
 fanotify_release+0x212/0x240 fs/notify/fanotify/fanotify_user.c:488
 __fput+0x1e1/0x520 fs/file_table.c:280
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29332 Comm: syz-executor.1 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/11 22:54 https://github.com/google/ktsan.git kcsan 94c006602e13 377d77fa .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.