================================================================== BUG: KASAN: slab-out-of-bounds in ip6_dst_lookup_tail+0x196a/0x1b30 net/ipv6/ip6_output.c:1070 Read of size 8 at addr ffff88806a69183f by task syz-executor.5/13686 CPU: 0 PID: 13686 Comm: syz-executor.5 Not tainted 5.2.0-rc2+ #15 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:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 ip6_dst_lookup_tail+0x196a/0x1b30 net/ipv6/ip6_output.c:1070 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1154 ip6_datagram_dst_update+0x5d8/0xc20 net/ipv6/datagram.c:91 ip6_datagram_release_cb net/ipv6/datagram.c:132 [inline] ip6_datagram_release_cb+0x4ed/0x550 net/ipv6/datagram.c:116 release_sock+0xba/0x1c0 net/core/sock.c:2940 udpv6_destroy_sock+0x29/0x150 net/ipv6/udp.c:1546 sk_common_release+0x6b/0x330 net/core/sock.c:3151 udp_lib_close+0x16/0x20 include/net/udp.h:206 inet_release+0xe0/0x1f0 net/ipv4/af_inet.c:431 inet6_release+0x53/0x80 net/ipv6/af_inet6.c:474 __sock_release+0xce/0x2a0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412f61 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007fffd8af1a70 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412f61 RDX: 0000001b2e120000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: 000000007b5fd88f R09: 000000007b5fd893 R10: 00007fffd8af1b50 R11: 0000000000000293 R12: 000000000076c358 R13: 00000000000cc0da R14: 00000000000cc107 R15: 000000000075bf2c Allocated by task 5626: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3326 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3488 dst_alloc+0x10e/0x200 net/core/dst.c:93 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:356 ip6_rt_pcpu_alloc net/ipv6/route.c:1257 [inline] rt6_make_pcpu_route net/ipv6/route.c:1286 [inline] ip6_pol_route+0x609/0xfd0 net/ipv6/route.c:2030 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2203 __fib6_rule_action net/ipv6/fib6_rules.c:230 [inline] fib6_rule_action+0x49c/0xb40 net/ipv6/fib6_rules.c:261 fib_rules_lookup+0x34c/0xa90 net/core/fib_rules.c:304 fib6_rule_lookup+0x384/0x5a0 net/ipv6/fib6_rules.c:108 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2232 ip6_route_output include/net/ip6_route.h:89 [inline] ip6_dst_lookup_tail+0xd10/0x1b30 net/ipv6/ip6_output.c:1026 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1154 sctp_v6_get_dst+0x785/0x1d80 net/sctp/ipv6.c:278 sctp_transport_route+0x12d/0x360 net/sctp/transport.c:297 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:663 sctp_process_param net/sctp/sm_make_chunk.c:2531 [inline] sctp_process_init+0x2491/0x2b10 net/sctp/sm_make_chunk.c:2344 sctp_cmd_process_init net/sctp/sm_sideeffect.c:667 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1369 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1179 [inline] sctp_do_sm+0x3a30/0x50e0 net/sctp/sm_sideeffect.c:1150 sctp_assoc_bh_rcv+0x343/0x660 net/sctp/associola.c:1059 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80 sctp_backlog_rcv+0x196/0xbe0 net/sctp/input.c:339 sk_backlog_rcv include/net/sock.h:950 [inline] __release_sock+0x129/0x390 net/core/sock.c:2418 release_sock+0x59/0x1c0 net/core/sock.c:2934 sctp_wait_for_connect+0x316/0x540 net/sctp/socket.c:9039 __sctp_connect+0xab2/0xcd0 net/sctp/socket.c:1226 sctp_connect net/sctp/socket.c:4846 [inline] sctp_inet_connect+0x29c/0x340 net/sctp/socket.c:4862 __sys_connect+0x264/0x330 net/socket.c:1840 __do_sys_connect net/socket.c:1851 [inline] __se_sys_connect net/socket.c:1848 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1848 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3698 dst_destroy+0x29e/0x3c0 net/core/dst.c:129 dst_destroy_rcu+0x16/0x19 net/core/dst.c:142 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291 __do_softirq+0x25c/0x94c kernel/softirq.c:293 The buggy address belongs to the object at ffff88806a691700 which belongs to the cache ip6_dst_cache of size 224 The buggy address is located 95 bytes to the right of 224-byte region [ffff88806a691700, ffff88806a6917e0) The buggy address belongs to the page: page:ffffea0001a9a440 refcount:1 mapcount:0 mapping:ffff88809bda9380 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002414c48 ffffea00027ea288 ffff88809bda9380 raw: 0000000000000000 ffff88806a6910c0 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806a691700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806a691780: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff88806a691800: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ^ ffff88806a691880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806a691900: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================