syzbot


WARNING in mptcp_pm_alloc_anno_list (2)

Status: upstream: reported on 2026/05/20 11:55
Subsystems: mptcp
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+55c2a5c871441261ed14@syzkaller.appspotmail.com
First crash: 18d, last: 6h14m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
7dc26c69-4898-4f8c-9d68-b7ea89cc171c assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in mptcp_pm_alloc_anno_list (2) 2026/06/01 23:36 2026/06/01 23:36 2026/06/02 00:33 386cc6dacdf7e3ebce9507beed6755d7e999554d
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 2 4d13h 18d 0/3 upstream: reported on 2026/05/19 14:10
upstream WARNING in mptcp_pm_alloc_anno_list mptcp -1 1 339d 335d 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:446 at mptcp_pm_alloc_anno_list+0x8bc/0x980 net/mptcp/pm.c:446, CPU#0: kworker/0:4/5734
Modules linked in:
CPU: 0 UID: 0 PID: 5734 Comm: kworker/0:4 Not tainted syzkaller #0 PREEMPT(full) 
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:446
Code: 06 31 f6 e9 bf fd ff ff e8 71 06 31 f6 90 0f 0b 90 e9 de f7 ff ff e8 63 06 31 f6 90 0f 0b 90 e9 34 f8 ff ff e8 55 06 31 f6 90 <0f> 0b 90 31 c0 e9 76 ff ff ff 48 c7 c1 e0 68 30 90 80 e1 07 80 c1
RSP: 0018:ffffc9000478f360 EFLAGS: 00010293
RAX: ffffffff8b94b05b RBX: 0000000000000000 RCX: ffff88807c345d00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff88806a600a50 R08: 0000000000020004 R09: 00000000aa1414ac
R10: 00000000aa1414ac R11: 0000000000000000 R12: ffff88806a600000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88807611d300
FS:  0000000000000000(0000) GS:ffff8881252a0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555593c7a38 CR3: 0000000075b9c000 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:1098
 mptcp_worker+0xd3/0x1420 net/mptcp/protocol.c:2998
 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 (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/06 22:10 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/06/06 22:07 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/06/06 22:07 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/06/06 22:03 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/06/06 21:59 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/06/06 21:58 upstream 8e65320d91cd cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/06/01 00:44 upstream 8d9c51eac648 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
2026/05/22 23:09 upstream cca95436be15 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in mptcp_pm_alloc_anno_list
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
2026/05/30 03:54 upstream 9215e74f228f 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in mptcp_pm_alloc_anno_list
2026/05/30 03:54 upstream 9215e74f228f 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in mptcp_pm_alloc_anno_list
* Struck through repros no longer work on HEAD.