================================================================== BUG: KASAN: slab-out-of-bounds in rt6_nexthop include/net/ip6_route.h:267 [inline] BUG: KASAN: slab-out-of-bounds in ip6_dst_lookup_tail+0x1882/0x1b30 net/ipv6/ip6_output.c:1009 Read of size 4 at addr ffff8880a46bbbaa by task syz-executor.0/21575 CPU: 1 PID: 21575 Comm: syz-executor.0 Not tainted 5.0.0+ #135 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 rt6_nexthop include/net/ip6_route.h:267 [inline] ip6_dst_lookup_tail+0x1882/0x1b30 net/ipv6/ip6_output.c:1009 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1092 sctp_v6_get_dst+0x785/0x1d80 net/sctp/ipv6.c:293 sctp_transport_route+0x132/0x370 net/sctp/transport.c:312 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:678 sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline] sctp_process_init+0x249f/0x2b20 net/sctp/sm_make_chunk.c:2361 sctp_sf_do_5_1B_init+0x8ba/0xe50 net/sctp/sm_statefuns.c:416 sctp_do_sm+0x124/0x53e0 net/sctp/sm_sideeffect.c:1188 sctp_endpoint_bh_rcv+0x451/0x950 net/sctp/endpointola.c:458 sctp_inq_push+0x1ea/0x290 net/sctp/inqueue.c:95 sctp_rcv+0x2818/0x3570 net/sctp/input.c:271 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1063 ip6_protocol_deliver_rcu+0x303/0x16c0 net/ipv6/ip6_input.c:394 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:443 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x1e7/0x320 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 process_backlog+0x206/0x750 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x4fa/0x1070 net/core/dev.c:6412 __do_softirq+0x266/0x95a kernel/softirq.c:293 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:338 do_softirq kernel/softirq.c:330 [inline] __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:190 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:684 [inline] ip6_finish_output2+0xbcf/0x2550 net/ipv6/ip6_output.c:121 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip6_xmit+0xe41/0x20c0 net/ipv6/ip6_output.c:275 sctp_v6_xmit+0x313/0x660 net/sctp/ipv6.c:232 sctp_packet_transmit+0x1bc4/0x36f0 net/sctp/output.c:641 sctp_packet_singleton net/sctp/outqueue.c:787 [inline] sctp_outq_flush_ctrl.constprop.0+0x6d4/0xd50 net/sctp/outqueue.c:918 sctp_outq_flush+0xe8/0x2780 net/sctp/outqueue.c:1200 sctp_outq_uncork+0x6c/0x80 net/sctp/outqueue.c:772 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1820 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1220 [inline] sctp_do_sm+0x559/0x53e0 net/sctp/sm_sideeffect.c:1191 sctp_primitive_ASSOCIATE+0x9d/0xd0 net/sctp/primitive.c:88 __sctp_connect+0x8cd/0xce0 net/sctp/socket.c:1226 __sctp_setsockopt_connectx+0x133/0x1a0 net/sctp/socket.c:1349 sctp_setsockopt_connectx_old net/sctp/socket.c:1365 [inline] sctp_setsockopt net/sctp/socket.c:4656 [inline] sctp_setsockopt+0x22cc/0x6d20 net/sctp/socket.c:4620 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3120 __sys_setsockopt+0x180/0x280 net/socket.c:2046 __do_sys_setsockopt net/socket.c:2057 [inline] __se_sys_setsockopt net/socket.c:2054 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2054 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458209 Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f901ee5cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000458209 RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000005 RBP: 000000000073bf00 R08: 000000000000001c R09: 0000000000000000 R10: 000000002055bfe4 R11: 0000000000000246 R12: 00007f901ee5d6d4 R13: 00000000004ccd38 R14: 00000000004daae0 R15: 00000000ffffffff Allocated by task 7807: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:436 [inline] slab_alloc mm/slab.c:3392 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3554 dst_alloc+0x10e/0x200 net/core/dst.c:109 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:355 ip6_rt_pcpu_alloc net/ipv6/route.c:1225 [inline] rt6_make_pcpu_route net/ipv6/route.c:1255 [inline] ip6_pol_route+0x743/0x1040 net/ipv6/route.c:1909 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2082 fib6_rule_lookup+0x128/0x560 net/ipv6/fib6_rules.c:118 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2111 ip6_route_output include/net/ip6_route.h:88 [inline] ip6_dst_lookup_tail+0xd10/0x1b30 net/ipv6/ip6_output.c:964 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1092 sctp_v6_get_dst+0x785/0x1d80 net/sctp/ipv6.c:293 sctp_transport_route+0x132/0x370 net/sctp/transport.c:312 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:678 sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline] sctp_process_init+0x249f/0x2b20 net/sctp/sm_make_chunk.c:2361 sctp_sf_do_5_1B_init+0x8ba/0xe50 net/sctp/sm_statefuns.c:416 sctp_do_sm+0x124/0x53e0 net/sctp/sm_sideeffect.c:1188 sctp_endpoint_bh_rcv+0x451/0x950 net/sctp/endpointola.c:458 sctp_inq_push+0x1ea/0x290 net/sctp/inqueue.c:95 sctp_rcv+0x2818/0x3570 net/sctp/input.c:271 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1063 ip6_protocol_deliver_rcu+0x303/0x16c0 net/ipv6/ip6_input.c:394 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:443 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x1e7/0x320 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 process_backlog+0x206/0x750 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x4fa/0x1070 net/core/dev.c:6412 __do_softirq+0x266/0x95a kernel/softirq.c:293 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8880a46bbac0 which belongs to the cache ip6_dst_cache of size 224 The buggy address is located 10 bytes to the right of 224-byte region [ffff8880a46bbac0, ffff8880a46bbba0) The buggy address belongs to the page: page:ffffea000291aec0 count:1 mapcount:0 mapping:ffff88821692f980 index:0xffff8880a46bb840 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002492cc8 ffffea0002840b88 ffff88821692f980 raw: ffff8880a46bb840 ffff8880a46bb0c0 0000000100000005 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a46bba80: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff8880a46bbb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880a46bbb80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a46bbc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a46bbc80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================