syzbot


WARNING in mptcp_pm_alloc_anno_list (2)

Status: upstream: reported on 2026/05/20 11:55
Subsystems: mptcp
[Documentation on labels]
Reported-by: syzbot+55c2a5c871441261ed14@syzkaller.appspotmail.com
First crash: 1d07h, last: 6h13m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mptcp?] WARNING in mptcp_pm_alloc_anno_list (2) 1 (2) 2026/05/20 12:05
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in mptcp_pm_alloc_anno_list -1 1 1d15h 1d15h 0/3 upstream: reported on 2026/05/19 14:10
upstream WARNING in mptcp_pm_alloc_anno_list mptcp -1 1 322d 318d 0/29 auto-obsoleted due to no activity on 2025/10/11 04:03

Sample crash report:
------------[ cut here ]------------
mptcp_pm_is_kernel(msk)
WARNING: net/mptcp/pm.c:436 at mptcp_pm_alloc_anno_list+0x8bc/0x980 net/mptcp/pm.c:436, CPU#0: kworker/0:2/30428
Modules linked in:
CPU: 0 UID: 0 PID: 30428 Comm: kworker/0:2 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events mptcp_worker
RIP: 0010:mptcp_pm_alloc_anno_list+0x8bc/0x980 net/mptcp/pm.c:436
Code: 54 2f f6 e9 bf fd ff ff e8 11 54 2f f6 90 0f 0b 90 e9 de f7 ff ff e8 03 54 2f f6 90 0f 0b 90 e9 34 f8 ff ff e8 f5 53 2f f6 90 <0f> 0b 90 31 c0 e9 76 ff ff ff 48 c7 c1 c0 ff 30 90 80 e1 07 80 c1
RSP: 0018:ffffc90003b17360 EFLAGS: 00010293
RAX: ffffffff8b9670cb RBX: 0000000000000000 RCX: ffff888055a5bd80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888058137890 R08: 0000000000020003 R09: 00000000aa1414ac
R10: 00000000aa1414ac R11: 0000000000000000 R12: ffff888058136e40
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888055622800
FS:  0000000000000000(0000) GS:ffff888125289000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2db0fff8 CR3: 000000003fef2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 mptcp_pm_create_subflow_or_signal_addr+0x1363/0x1860 net/mptcp/pm_kernel.c:373
 mptcp_pm_nl_subflow_established net/mptcp/pm_kernel.c:443 [inline]
 __mptcp_pm_kernel_worker+0x19ee/0x2100 net/mptcp/pm_kernel.c:1573
 mptcp_pm_worker+0x1bb/0x300 net/mptcp/pm.c:1069
 mptcp_worker+0xd3/0x1420 net/mptcp/protocol.c:2976
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
 kthread+0x389/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/20 23:24 upstream df685633c3db 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/05/19 21:48 upstream ab5fce87a778 223544dc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in mptcp_pm_alloc_anno_list
* Struck through repros no longer work on HEAD.