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BUG: KASAN: out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118
Read of size 8 at addr ffffc90018e17510 by task syz-executor.5/8758

CPU: 1 PID: 8758 Comm: syz-executor.5 Not tainted 5.8.0-rc3-next-20200703-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 csd_lock_record+0xcb/0xe0 kernel/smp.c:118
 flush_smp_call_function_queue+0x285/0x730 kernel/smp.c:391
 __sysvec_call_function_single+0x98/0x490 arch/x86/kernel/smp.c:248
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_call_function_single+0xe0/0x120 arch/x86/kernel/smp.c:243
 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:604
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4b/0x80 kernel/locking/spinlock.c:199
Code: c0 10 ff b4 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d ee 7a c8 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 db 01 63 f9 65 8b 05 44 7a 15 78 85 c0 74 02 5d
RSP: 0018:ffffc90018df6ec8 EFLAGS: 00000286
RAX: 1ffffffff1369fe2 RBX: ffff888051088000 RCX: 0000000000000006
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff87ec83ff
RBP: ffff8880ae735e00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880ae735e00
R13: ffff88808eabe0c0 R14: 0000000000000000 R15: 0000000000000001
 finish_lock_switch kernel/sched/core.c:3184 [inline]
 finish_task_switch+0x147/0x750 kernel/sched/core.c:3284
 context_switch kernel/sched/core.c:3448 [inline]
 __schedule+0x8bc/0x1e80 kernel/sched/core.c:4169
 preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:4427
 idtentry_exit_cond_resched arch/x86/entry/common.c:645 [inline]
 idtentry_exit_cond_rcu+0xc0/0xf0 arch/x86/entry/common.c:692
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:596
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:lock_acquire+0x270/0xad0 kernel/locking/lockdep.c:4962
Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 f8 06 00 00 48 83 3d 6d c1 5a 08 00 0f 84 a6 05 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7
RSP: 0018:ffffc90018df70f8 EFLAGS: 00000282
RAX: 1ffffffff1369fe0 RBX: ffff888051088000 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 93578a1fd679b66b RDI: 0000000000000282
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5a7a27
R10: fffffbfff18b4f44 R11: 0000000000000000 R12: 0000000000000002
R13: ffffffff89bc3040 R14: 0000000000000000 R15: ffff888051088000
 rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
 rcu_read_lock include/linux/rcupdate.h:634 [inline]
 sctp_v4_get_dst+0x583/0x1130 net/sctp/protocol.c:462
 sctp_transport_route+0x125/0x350 net/sctp/transport.c:297
 sctp_assoc_add_peer+0x60c/0x10b0 net/sctp/associola.c:659
 sctp_process_param net/sctp/sm_make_chunk.c:2520 [inline]
 sctp_process_init+0x21c7/0x2840 net/sctp/sm_make_chunk.c:2341
 sctp_cmd_process_init net/sctp/sm_sideeffect.c:670 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1377 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1185 [inline]
 sctp_do_sm+0x2b9f/0x4d80 net/sctp/sm_sideeffect.c:1156
 sctp_assoc_bh_rcv+0x386/0x6c0 net/sctp/associola.c:1044
 sctp_inq_push+0x1da/0x270 net/sctp/inqueue.c:80
 sctp_backlog_rcv+0x19e/0x5c0 net/sctp/input.c:344
 sk_backlog_rcv include/net/sock.h:1005 [inline]
 __release_sock+0x134/0x3a0 net/core/sock.c:2541
 release_sock+0x54/0x1b0 net/core/sock.c:3057
 sctp_wait_for_connect+0x30f/0x540 net/sctp/socket.c:9302
 __sctp_connect+0x96b/0xc00 net/sctp/socket.c:1247
 __sctp_setsockopt_connectx+0x12d/0x180 net/sctp/socket.c:1343
 sctp_setsockopt_connectx_old net/sctp/socket.c:1359 [inline]
 sctp_setsockopt net/sctp/socket.c:4713 [inline]
 sctp_setsockopt+0x1619/0x70d0 net/sctp/socket.c:4677
 __sys_setsockopt+0x24a/0x480 net/socket.c:2127
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:367
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007fcc707c5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000506160 RCX: 000000000045cb29
RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 000000000000001c R09: 0000000000000000
R10: 000000002055bfe4 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000b2b R14: 00000000004d7e20 R15: 00007fcc707c66d4


Memory state around the buggy address:
 ffffc90018e17400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90018e17480: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>ffffc90018e17500: 00 00 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00
                         ^
 ffffc90018e17580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90018e17600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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