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INFO: rcu detected stall in sctp_inet_connect (8)

Status: auto-obsoleted due to no activity on 2026/06/07 00:09
Subsystems: sctp
Labels: prio:high
[Documentation on labels]
First crash: 237d, last: 92d
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
af8431b6-5179-4caf-8b18-4b71440149ab assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ✅ PeripheralTrigger: ✅ RemoteTrigger: ✅ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ✅ VMHostTrigger: ✅ INFO: rcu detected stall in sctp_inet_connect (8) 2026/05/13 16:14 2026/05/13 16:14 2026/05/13 18:27 71153e5d9da49247dc7f1194a9cc04fb90c64f9c
4e32fd88-dba8-488a-bf57-7ae8d3a31cd6 repro INFO: rcu detected stall in sctp_inet_connect (8) 2026/03/06 04:13 2026/03/06 04:13 2026/03/06 04:23 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sctp_inet_connect (2) mm 1 4 2343d 2429d 0/29 auto-closed as invalid on 2020/04/07 07:45
upstream INFO: rcu detected stall in sctp_inet_connect (5) net 1 1 1100d 1100d 0/29 auto-obsoleted due to no activity on 2023/09/02 17:34
linux-4.19 INFO: rcu detected stall in sctp_inet_connect 1 2 2122d 2187d 0/1 auto-closed as invalid on 2020/12/15 01:43
upstream INFO: rcu detected stall in sctp_inet_connect (7) sctp 1 4 399d 514d 0/29 auto-obsoleted due to no activity on 2025/08/03 11:32
upstream INFO: rcu detected stall in sctp_inet_connect (6) mm 1 1 624d 624d 0/29 auto-obsoleted due to no activity on 2024/12/22 03:14
upstream INFO: rcu detected stall in sctp_inet_connect (4) sctp 1 6 1664d 1766d 0/29 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in sctp_inet_connect (3) sctp 1 12 2030d 2241d 0/29 auto-closed as invalid on 2021/02/14 17:57
upstream INFO: rcu detected stall in sctp_inet_connect netfilter 1 1 2647d 2647d 0/29 auto-closed as invalid on 2019/09/07 12:17

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3942/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=225433, q=2074 ncpus=1)
task:syz.3.13431     state:S stack:25744 pid:3942  tgid:3941  ppid:5825   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6908
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7235
 irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872
Code: 05 7b d2 28 12 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 46 50 f5 0e 0f 82 c2 02 00 00 8b 35 0e 84 f5 0e 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 1d d2 28 12 0f 85 02 03 00 00 48 83 c4
RSP: 0018:ffffc90003e07068 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8de57654 RDI: ffffffff8c1af920
RBP: ffffffff8e7e7420 R08: 000000000e53ecb2 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 sctp_transport_new+0xa4/0x760 net/sctp/transport.c:95
 sctp_assoc_add_peer+0x302/0x14f0 net/sctp/associola.c:617
 sctp_process_param net/sctp/sm_make_chunk.c:2546 [inline]
 sctp_process_init+0x26bd/0x2d00 net/sctp/sm_make_chunk.c:2366
 sctp_cmd_process_init net/sctp/sm_sideeffect.c:712 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1395 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline]
 sctp_do_sm+0x3c4e/0x5be0 net/sctp/sm_sideeffect.c:1175
 sctp_assoc_bh_rcv+0x392/0x6f0 net/sctp/associola.c:1034
 sctp_inq_push+0x1db/0x280 net/sctp/inqueue.c:88
 sctp_backlog_rcv+0x169/0x590 net/sctp/input.c:331
 sk_backlog_rcv include/net/sock.h:1185 [inline]
 __release_sock+0x3a2/0x440 net/core/sock.c:3213
 release_sock+0x5a/0x220 net/core/sock.c:3795
 sctp_wait_for_connect+0x1ed/0x610 net/sctp/socket.c:9393
 __sctp_connect+0x9bb/0xc70 net/sctp/socket.c:1248
 sctp_connect net/sctp/socket.c:4818 [inline]
 sctp_inet_connect+0x15f/0x220 net/sctp/socket.c:4833
 __sys_connect_file+0x141/0x1a0 net/socket.c:2089
 __sys_connect+0x141/0x170 net/socket.c:2108
 __do_sys_connect net/socket.c:2114 [inline]
 __se_sys_connect net/socket.c:2111 [inline]
 __x64_sys_connect+0x72/0xb0 net/socket.c:2111
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7dcd19c799
RSP: 002b:00007f7dce0e2028 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f7dcd415fa0 RCX: 00007f7dcd19c799
RDX: 0000000000000054 RSI: 0000200000000080 RDI: 0000000000000003
RBP: 00007f7dcd232bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7dcd416038 R14: 00007f7dcd415fa0 R15: 00007ffde3cdf4d8
 </TASK>
net_ratelimit: 5468 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 7187 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:42:dd:89:78:63, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:42:dd:89:78:63, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:02:42:dd:89:78:63, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/09 00:04 upstream 014441d1e4b2 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in sctp_inet_connect
2025/12/30 23:57 upstream dbf8fe85a16a d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in sctp_inet_connect
2025/11/26 17:21 upstream 30f09200cc4a c116feb4 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in sctp_inet_connect
2025/10/25 05:38 upstream d2818517e348 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in sctp_inet_connect
2025/10/14 23:57 upstream 9b332cece987 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in sctp_inet_connect
* Struck through repros no longer work on HEAD.