INFO: rcu detected stall in sctp_setsockopt (2)

Status: upstream: reported on 2026/05/28 16:14
Reported-by: syzbot+75f61b34664ddb3f1cd0@syzkaller.appspotmail.com
First crash: 135d, last: 21d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sctp_setsockopt 1 1 719d 719d 0/3 auto-obsoleted due to no activity on 2025/01/29 14:06
upstream INFO: rcu detected stall in sctp_setsockopt net 1 8 2585d 2791d 0/29 auto-closed as invalid on 2019/12/12 00:34
linux-4.19 INFO: rcu detected stall in sctp_setsockopt 1 3 2263d 2310d 0/1 auto-closed as invalid on 2020/11/28 08:55
upstream INFO: rcu detected stall in sctp_setsockopt (2) sctp 1 8 2232d 2371d 0/29 auto-closed as invalid on 2020/11/28 11:26
linux-6.1 INFO: rcu detected stall in sctp_setsockopt 1 1 161d 161d 0/3 auto-obsoleted due to no activity on 2026/08/10 14:43

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=e3b/1/0x4000000000000000 softirq=53356/53357 fqs=4011 
	(t=10500 jiffies g=68841 q=2320)
NMI backtrace for cpu 0
CPU: 0 PID: 19689 Comm: syz.5.2883 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22d/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31f/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ec/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:ffs arch/x86/include/asm/bitops.h:297 [inline]
RIP: 0010:handle_softirqs+0x1a4/0x830 kernel/softirq.c:564
Code: 24 78 44 89 64 24 30 0f b7 db 48 c7 c7 e0 13 2a 8a e8 20 0a 78 08 65 66 c7 05 06 5d ba 7e 00 00 e8 71 04 36 00 fb 89 5c 24 3c <b8> ff ff ff ff 0f bc 44 24 3c 41 89 c6 41 ff c6 0f 85 d2 00 00 00
RSP: 0018:ffffc90000007e20 EFLAGS: 00000282
RAX: 9c08edf9297fe000 RBX: 0000000000000002 RCX: 9c08edf9297fe000
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a48c0
RBP: ffffc90000007f30 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 000000000000000a
R13: 0000000000000000 R14: ffff88808d761dc0 R15: dffffc0000000000
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_lock_switch+0x12f/0x290 kernel/sched/core.c:4804
Code: 83 c7 18 be ff ff ff ff e8 8e da 6c 08 85 c0 74 46 4d 85 ff 75 62 0f 1f 44 00 00 48 89 df e8 78 4a 76 08 e8 93 e3 2a 00 fb 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 2f 0e fe ff 43 80 3c 2c
RSP: 0018:ffffc90003d17738 EFLAGS: 00000286
RAX: 9c08edf9297fe000 RBX: ffff88802b589dc0 RCX: 9c08edf9297fe000
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a48c0
RBP: 1ffff11017207613 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 1ffff110172075c1
R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000
 finish_task_switch+0x12f/0x650 kernel/sched/core.c:4921
 context_switch kernel/sched/core.c:5052 [inline]
 __schedule+0x11cb/0x4350 kernel/sched/core.c:6395
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:435
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:qlist_free_all+0x2d/0x90 mm/kasan/quarantine.c:176
Code: 56 41 55 41 54 53 4c 8b 3f 4d 85 ff 74 6d 49 89 f6 48 89 fb 49 bc 00 00 00 00 00 ea ff ff eb 1a 4c 01 e0 48 8b 70 18 4d 8b 2f <4c> 89 ff e8 db 03 00 00 4d 89 ef 4d 85 ed 74 2a 4c 89 f6 4d 85 f6
RSP: 0018:ffffc90003d17b00 EFLAGS: 00000282
RAX: ffffea0001e80e40 RBX: ffffc90003d17b30 RCX: ffffea0001e83440
RDX: 0000000000000000 RSI: ffff888140005000 RDI: 0000000000000000
RBP: ffffc90003d17d88 R08: ffff88801bfde600 R09: 0000000080070003
R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffea0000000000
R13: ffff888089f46000 R14: 0000000000000000 R15: ffff88807a039460
 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 __kmalloc_track_caller+0x187/0x330 mm/slub.c:4930
 memdup_sockptr include/linux/sockptr.h:74 [inline]
 sctp_setsockopt+0x7d/0xf80 net/sctp/socket.c:4597
 __sys_setsockopt+0x2bf/0x3d0 net/socket.c:2213
 __do_sys_setsockopt net/socket.c:2224 [inline]
 __se_sys_setsockopt net/socket.c:2221 [inline]
 __x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2221
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1ff498b159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1ff2be3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f1ff4c12fa0 RCX: 00007f1ff498b159
RDX: 0000000000000014 RSI: 0000000000000084 RDI: 0000000000000004
RBP: 00007f1ff4a2206b R08: 0000000000000008 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1ff4c13038 R14: 00007f1ff4c12fa0 R15: 00007fff6a733778
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/19 23:02 linux-5.15.y 0248c33e835e 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sctp_setsockopt
2026/07/17 11:54 linux-5.15.y c86c4726e7f0 7f27c57a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sctp_setsockopt
2026/05/28 16:13 linux-5.15.y 241d66fa280c 681715f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sctp_setsockopt
* Struck through repros no longer work on HEAD.