syzbot


KCSAN: data-race in drop_nlink / generic_fillattr (8)

Status: auto-obsoleted due to no activity on 2024/11/23 13:06
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+f88da83995d0edba3126@syzkaller.appspotmail.com
First crash: 48d, last: 48d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in drop_nlink / generic_fillattr (4) fs 2 646d 689d 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 316d 323d 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 274d 280d 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 393d 362d 0/28 auto-obsoleted due to no activity on 2023/12/25 00:01
upstream KCSAN: data-race in drop_nlink / generic_fillattr (3) fs 22 1151d 1362d 0/28 auto-closed as invalid on 2021/11/16 10:39
upstream KCSAN: data-race in drop_nlink / generic_fillattr fs 9 1542d 1617d 0/28 auto-closed as invalid on 2020/10/22 03:32
upstream KCSAN: data-race in drop_nlink / generic_fillattr (2) fs 8 1416d 1460d 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 0xffff888111928698 of 4 bytes by task 3260 on cpu 1:
 drop_nlink+0x3b/0x90 fs/inode.c:337
 shmem_unlink+0x163/0x180 mm/shmem.c:3696
 vfs_unlink+0x275/0x430 fs/namei.c:4469
 do_unlinkat+0x236/0x4c0 fs/namei.c:4533
 __do_sys_unlink fs/namei.c:4581 [inline]
 __se_sys_unlink fs/namei.c:4579 [inline]
 __x64_sys_unlink+0x2e/0x40 fs/namei.c:4579
 x64_sys_call+0x280f/0x2d60 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 0xffff888111928698 of 4 bytes by task 3262 on cpu 0:
 generic_fillattr+0xf8/0x2f0 fs/stat.c:55
 shmem_getattr+0x17b/0x200 mm/shmem.c:1169
 vfs_getattr_nosec fs/stat.c:166 [inline]
 vfs_getattr+0x19b/0x1e0 fs/stat.c:207
 vfs_statx_path fs/stat.c:251 [inline]
 vfs_statx+0x134/0x2f0 fs/stat.c:315
 vfs_fstatat+0xec/0x110 fs/stat.c:341
 __do_sys_newfstatat fs/stat.c:505 [inline]
 __se_sys_newfstatat+0x58/0x260 fs/stat.c:499
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:499
 x64_sys_call+0x141f/0x2d60 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: 3262 Comm: udevd Tainted: G        W          6.12.0-rc3-syzkaller-00389-g3d5ad2d4eca3 #0
Tainted: [W]=WARN
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
2024/10/19 13:06 upstream 3d5ad2d4eca3 cd6fc0a3 .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.