SYZFAIL: netlink_send_ext: bad netlink ack type

Status: auto-obsoleted due to no activity on 2025/09/10 04:42
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+993a4f1fdde3285672af@syzkaller.appspotmail.com
First crash: 1160d, last: 878d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2023/06/11 upstream (ToT) 022ce8862dff syz [report] SYZFAIL: netlink_send_ext: bad netlink ack type
2025/09/10 upstream (ToT) 9dd1835ecda5 syz Didn't crash
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 SYZFAIL: netlink_send_ext: bad netlink ack type origin:upstream -1 syz error 1 393d 1159d 0/3 auto-obsoleted due to no activity on 2025/10/24 18:58
linux-4.14 SYZFAIL: netlink_send_ext: bad netlink ack type -1 1 1970d 1970d 0/1 auto-closed as invalid on 2021/07/21 03:33
upstream SYZFAIL: netlink_send_ext: bad netlink ack type wireless -1 syz inconclusive inconclusive 150 365d 1999d 0/29 auto-obsoleted due to no activity on 2025/11/12 02:25
linux-4.19 SYZFAIL: netlink_send_ext: bad netlink ack type -1 syz error 20 1617d 1997d 0/1 upstream: reported syz repro on 2021/02/23 18:14
▶ ▼ Fix bisection attempts (4)
Created Duration User Patch Repo Result
2024/06/12 17:41 13m bisect fix linux-6.1.y error job log
2024/03/19 05:06 1h50m bisect fix linux-6.1.y OK (0) job log log
2024/01/02 08:13 1h34m bisect fix linux-6.1.y OK (0) job log log
2023/12/01 23:13 1h42m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
1970/01/01 00:04:45 [FATAL] executor failed 11 times: executor 0: exit status 67
SYZFAIL: netlink_send_ext: bad netlink ack type
type=40 (errno 22: Invalid argument)
SYZFAIL: child failed
 (errno 0: Success)
loop exited with status 67

SYZFAIL: netlink_send_ext: bad netlink ack type
type=40 (errno 22: Invalid argument)
SYZFAIL: child failed
 (errno 0: Success)
loop exited with status 67

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/11 04:55 linux-6.1.y 2f3918bc53fb 49519f06 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 SYZFAIL: netlink_send_ext: bad netlink ack type
* Struck through repros no longer work on HEAD.