syzbot


KCSAN: data-race in fsnotify_perm / setattr_copy (2)

Status: auto-closed as invalid on 2021/10/19 09:08
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 438d, last: 438d
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 501d 501d 0/24 auto-closed as invalid on 2021/08/17 01:02
upstream KCSAN: data-race in fsnotify_perm / setattr_copy (3) 1 311d 311d 0/24 auto-closed as invalid on 2022/02/23 05:39

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

write to 0xffff888133ce69f8 of 2 bytes by task 6944 on cpu 1:
 setattr_copy+0x1af/0x1c0 fs/attr.c:247
 ext4_setattr+0x5ea/0xef0 fs/ext4/inode.c:5530
 notify_change+0x8a3/0xac0 fs/attr.c:410
 chmod_common+0x13c/0x270 fs/open.c:581
 do_fchmodat fs/open.c:620 [inline]
 __do_sys_chmod fs/open.c:638 [inline]
 __se_sys_chmod fs/open.c:636 [inline]
 __x64_sys_chmod+0x9b/0x120 fs/open.c:636
 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

read to 0xffff888133ce69f8 of 2 bytes by task 6923 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_permission+0x87/0xa0 security/security.c:1510
 rw_verify_area+0x94/0x150 fs/read_write.c:389
 do_splice_to fs/splice.c:787 [inline]
 splice_direct_to_actor+0x23a/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x63e/0xbb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1308 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0xb9/0x140 fs/read_write.c:1300
 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: 0x8000 -> 0x80a4

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6923 Comm: syz-executor.2 Tainted: G        W         5.15.0-rc1-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 2021/09/14 09:03 upstream d0ee23f9d78b 58d09404 .config log report info KCSAN: data-race in fsnotify_perm / setattr_copy
* Struck through repros no longer work on HEAD.