syzbot


KCSAN: data-race in drop_nlink / generic_fillattr (9)

Status: moderation: reported on 2024/12/13 23:17
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+9641ae66a73e90af8f25@syzkaller.appspotmail.com
First crash: 7d14h, last: 7d14h
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in drop_nlink / generic_fillattr (4) fs 2 661d 703d 0/28 auto-obsoleted due to no activity on 2023/04/11 17:00
upstream KCSAN: data-race in drop_nlink / generic_fillattr (6) fs 2 330d 337d 0/28 auto-obsoleted due to no activity on 2024/02/29 22:16
upstream KCSAN: data-race in drop_nlink / generic_fillattr (7) fs 2 288d 294d 0/28 auto-obsoleted due to no activity on 2024/04/11 18:19
upstream KCSAN: data-race in drop_nlink / generic_fillattr (5) fs 2 407d 376d 0/28 auto-obsoleted due to no activity on 2023/12/25 00:01
upstream KCSAN: data-race in drop_nlink / generic_fillattr (8) fs 1 63d 63d 0/28 auto-obsoleted due to no activity on 2024/11/23 13:06
upstream KCSAN: data-race in drop_nlink / generic_fillattr (3) fs 22 1166d 1376d 0/28 auto-closed as invalid on 2021/11/16 10:39
upstream KCSAN: data-race in drop_nlink / generic_fillattr fs 9 1556d 1631d 0/28 auto-closed as invalid on 2020/10/22 03:32
upstream KCSAN: data-race in drop_nlink / generic_fillattr (2) fs 8 1430d 1475d 0/28 auto-closed as invalid on 2021/02/25 00:13

Sample crash report:
==================================================================
BUG: KCSAN: data-race in drop_nlink / generic_fillattr

write to 0xffff8881188c6f48 of 4 bytes by task 13944 on cpu 1:
 drop_nlink+0x3b/0x90 fs/inode.c:408
 shmem_unlink+0x154/0x170 mm/shmem.c:3806
 vfs_unlink+0x275/0x430 fs/namei.c:4523
 do_unlinkat+0x237/0x4d0 fs/namei.c:4587
 __do_sys_unlink fs/namei.c:4635 [inline]
 __se_sys_unlink fs/namei.c:4633 [inline]
 __x64_sys_unlink+0x2e/0x40 fs/namei.c:4633
 x64_sys_call+0x2329/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881188c6f48 of 4 bytes by task 14765 on cpu 0:
 generic_fillattr+0xf8/0x330 fs/stat.c:91
 shmem_getattr+0x17b/0x200 mm/shmem.c:1177
 vfs_getattr_nosec fs/stat.c:208 [inline]
 vfs_getattr fs/stat.c:246 [inline]
 vfs_statx_path+0x171/0x2d0 fs/stat.c:283
 vfs_statx+0xe1/0x170 fs/stat.c:347
 vfs_fstatat fs/stat.c:366 [inline]
 __do_sys_newfstatat fs/stat.c:530 [inline]
 __se_sys_newfstatat+0xdc/0x300 fs/stat.c:524
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:524
 x64_sys_call+0x236d/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:263
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 14765 Comm: udevd Not tainted 6.13.0-rc2-syzkaller-00192-g243f750a2df0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/13 23:16 upstream 243f750a2df0 7cbfbb3a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in drop_nlink / generic_fillattr
* Struck through repros no longer work on HEAD.