================================================================== BUG: KASAN: null-ptr-deref in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] BUG: KASAN: null-ptr-deref in atomic_fetch_add_unless include/linux/atomic.h:575 [inline] BUG: KASAN: null-ptr-deref in atomic_add_unless include/linux/atomic.h:597 [inline] BUG: KASAN: null-ptr-deref in dst_hold_safe include/net/dst.h:308 [inline] BUG: KASAN: null-ptr-deref in ip6_hold_safe+0xca/0x620 net/ipv6/route.c:1023 Read of size 4 at addr 0000000000000076 by task syz-executor0/11107 CPU: 0 PID: 11107 Comm: syz-executor0 Not tainted 5.0.0-rc3+ #23 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+0x1db/0x2d0 lib/dump_stack.c:113 kasan_report.cold+0x5/0x40 mm/kasan/report.c:321 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:100 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] atomic_fetch_add_unless include/linux/atomic.h:575 [inline] atomic_add_unless include/linux/atomic.h:597 [inline] dst_hold_safe include/net/dst.h:308 [inline] ip6_hold_safe+0xca/0x620 net/ipv6/route.c:1023 rt6_get_pcpu_route net/ipv6/route.c:1243 [inline] ip6_pol_route+0x3a3/0x1490 net/ipv6/route.c:1892 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2068 fib6_rule_lookup+0x12f/0x870 net/ipv6/fib6_rules.c:118 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2097 ip6_route_output include/net/ip6_route.h:88 [inline] ip6_dst_lookup_tail+0xe18/0x1d50 net/ipv6/ip6_output.c:958 ip6_dst_lookup_flow+0xca/0x270 net/ipv6/ip6_output.c:1086 sctp_v6_get_dst+0x7d5/0x2240 net/sctp/ipv6.c:292 sctp_transport_route+0x132/0x370 net/sctp/transport.c:311 sctp_assoc_add_peer+0x5f7/0x10e0 net/sctp/associola.c:678 sctp_process_param net/sctp/sm_make_chunk.c:2543 [inline] sctp_process_init+0xe63/0x2910 net/sctp/sm_make_chunk.c:2356 sctp_sf_do_5_1B_init+0x908/0xf80 net/sctp/sm_statefuns.c:416 sctp_do_sm+0x197/0x7020 net/sctp/sm_sideeffect.c:1188 sctp_endpoint_bh_rcv+0x471/0x9b0 net/sctp/endpointola.c:456 sctp_inq_push+0x288/0x3a0 net/sctp/inqueue.c:95 sctp_rcv+0x2cef/0x4010 net/sctp/input.c:271 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1062 ip6_protocol_deliver_rcu+0x3aa/0x1940 net/ipv6/ip6_input.c:394 audit: type=1804 audit(1548544008.445:44): pid=11127 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor1" name="/root/syzkaller-testdir272181357/syzkaller.vNYm9q/140/memory.events" dev="sda1" ino=16888 res=1 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+0xf9/0x600 net/ipv6/ip6_input.c:443 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x177/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ipv6_rcv+0x113/0x650 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x160/0x210 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+0x76d/0x1930 net/core/dev.c:6412 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:696 [inline] ip6_finish_output2+0xca9/0x28e0 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+0x23c/0xa00 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+0xee1/0x24a0 net/ipv6/ip6_output.c:275 sctp_v6_xmit+0x3bf/0x780 net/sctp/ipv6.c:232 sctp_packet_transmit+0x1e49/0x3be0 net/sctp/output.c:641 audit: type=1804 audit(1548544008.445:45): pid=11124 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor1" name="/root/syzkaller-testdir272181357/syzkaller.vNYm9q/140/memory.events" dev="sda1" ino=16888 res=1 sctp_packet_singleton net/sctp/outqueue.c:787 [inline] sctp_outq_flush_ctrl.constprop.0+0x7c9/0xe50 net/sctp/outqueue.c:918 sctp_outq_flush+0x290/0x3580 net/sctp/outqueue.c:1200 audit: type=1804 audit(1548544008.445:46): pid=11127 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor1" name="/root/syzkaller-testdir272181357/syzkaller.vNYm9q/140/memory.events" dev="sda1" ino=16888 res=1 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+0x624/0x7020 net/sctp/sm_sideeffect.c:1191 sctp_primitive_ASSOCIATE+0x9d/0xd0 net/sctp/primitive.c:88 __sctp_connect+0x999/0xd90 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:4380 [inline] sctp_setsockopt+0x22c2/0x6f80 net/sctp/socket.c:4344 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3016 __sys_setsockopt+0x1b0/0x3a0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458099 Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa555222c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000458099 RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000006 RBP: 000000000073bfa0 R08: 000000000000001c R09: 0000000000000000 R10: 000000002055bfe4 R11: 0000000000000246 R12: 00007fa5552236d4 R13: 00000000004ccb50 R14: 00000000004da770 R15: 00000000ffffffff ==================================================================