================================================================== BUG: KASAN: use-after-free in __list_add_valid+0x8f/0xac lib/list_debug.c:26 Read of size 8 at addr ffff8881c0f9d470 by task syz-executor1/15344 CPU: 0 PID: 15344 Comm: syz-executor1 Not tainted 4.20.0-rc6+ #336 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __list_add_valid+0x8f/0xac lib/list_debug.c:26 __list_add include/linux/list.h:60 [inline] list_add_tail include/linux/list.h:93 [inline] neigh_alloc net/core/neighbour.c:395 [inline] ___neigh_create+0x14b7/0x2600 net/core/neighbour.c:553 __neigh_create+0x30/0x40 net/core/neighbour.c:640 neigh_create include/net/neighbour.h:319 [inline] __neigh_lookup_errno include/net/neighbour.h:529 [inline] arp_req_set+0x59d/0xaa0 net/ipv4/arp.c:1066 arp_ioctl+0x48b/0xae0 net/ipv4/arp.c:1230 inet_ioctl+0x237/0x360 net/ipv4/af_inet.c:932 sock_do_ioctl+0xeb/0x420 net/socket.c:950 sock_ioctl+0x313/0x690 net/socket.c:1074 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457659 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb301764c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457659 RDX: 0000000020000080 RSI: 0000000000008955 RDI: 0000000000000003 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb3017656d4 R13: 00000000004c2710 R14: 00000000004d4688 R15: 00000000ffffffff Allocated by task 14954: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 kmalloc include/linux/slab.h:546 [inline] kzalloc include/linux/slab.h:741 [inline] sctp_transport_new+0x126/0x870 net/sctp/transport.c:111 sctp_assoc_add_peer+0x2de/0x10d0 net/sctp/associola.c:637 sctp_process_param net/sctp/sm_make_chunk.c:2543 [inline] sctp_process_init+0xfba/0x29c0 net/sctp/sm_make_chunk.c:2356 sctp_sf_do_5_1D_ce+0x4ae/0x1500 net/sctp/sm_statefuns.c:782 sctp_do_sm+0x1c1/0x7190 net/sctp/sm_sideeffect.c:1188 sctp_endpoint_bh_rcv+0x465/0x960 net/sctp/endpointola.c:456 sctp_inq_push+0x280/0x370 net/sctp/inqueue.c:95 sctp_rcv+0x2e50/0x4170 net/sctp/input.c:271 ip_protocol_deliver_rcu+0xb5/0xa10 net/ipv4/ip_input.c:208 ip_local_deliver_finish+0x243/0x390 net/ipv4/ip_input.c:234 NF_HOOK include/linux/netfilter.h:289 [inline] ip_local_deliver+0x1e9/0x750 net/ipv4/ip_input.c:255 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0x1f9/0x300 net/ipv4/ip_input.c:414 NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0xed/0x600 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4971 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5081 process_backlog+0x24e/0x7a0 net/core/dev.c:5911 napi_poll net/core/dev.c:6334 [inline] net_rx_action+0x7fa/0x19b0 net/core/dev.c:6400 __do_softirq+0x308/0xb7e kernel/softirq.c:292 Freed by task 16: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 sctp_transport_destroy_rcu+0x4a/0x60 net/sctp/transport.c:163 __rcu_reclaim kernel/rcu/rcu.h:240 [inline] rcu_do_batch kernel/rcu/tree.c:2437 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2716 [inline] rcu_process_callbacks+0x100a/0x1ac0 kernel/rcu/tree.c:2697 __do_softirq+0x308/0xb7e kernel/softirq.c:292 The buggy address belongs to the object at ffff8881c0f9d200 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 624 bytes inside of 1024-byte region [ffff8881c0f9d200, ffff8881c0f9d600) The buggy address belongs to the page: page:ffffea000703e700 count:1 mapcount:0 mapping:ffff8881da800ac0 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000010200(slab|head) raw: 02fffc0000010200 ffffea000703e608 ffffea00070d7688 ffff8881da800ac0 raw: 0000000000000000 ffff8881c0f9c000 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881c0f9d300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881c0f9d380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881c0f9d400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881c0f9d480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881c0f9d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================