syzbot


KCSAN: data-race in drop_nlink / generic_fillattr (5)

Status: auto-obsoleted due to no activity on 2023/12/25 00:01
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+ffefe338453f2ecc3aaf@syzkaller.appspotmail.com
First crash: 209d, last: 193d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in drop_nlink / generic_fillattr (4) fs 2 446d 489d 0/26 auto-obsoleted due to no activity on 2023/04/11 17:00
upstream KCSAN: data-race in drop_nlink / generic_fillattr (6) fs 2 116d 122d 0/26 auto-obsoleted due to no activity on 2024/02/29 22:16
upstream KCSAN: data-race in drop_nlink / generic_fillattr (7) fs 2 74d 80d 0/26 auto-obsoleted due to no activity on 2024/04/11 18:19
upstream KCSAN: data-race in drop_nlink / generic_fillattr (3) fs 22 951d 1162d 0/26 auto-closed as invalid on 2021/11/16 10:39
upstream KCSAN: data-race in drop_nlink / generic_fillattr fs 9 1341d 1417d 0/26 auto-closed as invalid on 2020/10/22 03:32
upstream KCSAN: data-race in drop_nlink / generic_fillattr (2) fs 8 1215d 1260d 0/26 auto-closed as invalid on 2021/02/25 00:13

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

write to 0xffff888125adde28 of 4 bytes by task 32498 on cpu 0:
 drop_nlink+0x3b/0x90 fs/inode.c:331
 shmem_unlink+0x169/0x180 mm/shmem.c:3355
 shmem_rename2+0x1dc/0x2c0 mm/shmem.c:3434
 vfs_rename+0x833/0x9b0 fs/namei.c:4844
 do_renameat2+0x7b3/0xa40 fs/namei.c:4996
 __do_sys_rename fs/namei.c:5042 [inline]
 __se_sys_rename fs/namei.c:5040 [inline]
 __x64_sys_rename+0x5c/0x70 fs/namei.c:5040
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888125adde28 of 4 bytes by task 2781 on cpu 1:
 generic_fillattr+0xf8/0x2f0 fs/stat.c:55
 shmem_getattr+0x17b/0x200 mm/shmem.c:1121
 vfs_getattr_nosec fs/stat.c:135 [inline]
 vfs_getattr fs/stat.c:172 [inline]
 vfs_fstat+0x1b2/0x460 fs/stat.c:194
 vfs_fstatat+0x85/0x100 fs/stat.c:291
 __do_sys_newfstatat fs/stat.c:459 [inline]
 __se_sys_newfstatat+0x58/0x260 fs/stat.c:453
 __x64_sys_newfstatat+0x55/0x60 fs/stat.c:453
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2781 Comm: udevd Tainted: G        W          6.6.0-syzkaller-15494-g6bc986ab839c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/09 15:50 upstream 6bc986ab839c 56230772 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in drop_nlink / generic_fillattr
2023/10/24 14:28 upstream d88520ad73b7 af8d2e46 .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.