netlink: 4 bytes leftover after parsing attributes in process `syz-executor.3'. bridge5: port 1(syz_tun) entered blocking state bridge5: port 1(syz_tun) entered disabled state ================================================================== device syz_tun entered promiscuous mode BUG: KASAN: slab-out-of-bounds in _decode_session6+0xf56/0x1370 net/ipv6/xfrm6_policy.c:137 Read of size 1 at addr ffff88809365bdc8 by task syz-executor.3/11975 CPU: 1 PID: 11975 Comm: syz-executor.3 Not tainted 4.19.130-syzkaller #0 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+0x1fc/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430 _decode_session6+0xf56/0x1370 net/ipv6/xfrm6_policy.c:137 __xfrm_decode_session+0x5a/0x130 net/xfrm/xfrm_policy.c:2299 xfrm_decode_session_reverse include/net/xfrm.h:1244 [inline] icmpv6_route_lookup+0x2fb/0x460 net/ipv6/icmp.c:372 icmp6_send+0x150d/0x2230 net/ipv6/icmp.c:555 icmpv6_send+0xde/0x210 net/ipv6/ip6_icmp.c:43 ip6_link_failure+0x26/0x4e0 net/ipv6/route.c:2297 dst_link_failure include/net/dst.h:430 [inline] ip6_tnl_xmit+0x474/0x3500 net/ipv6/ip6_tunnel.c:1227 ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1381 [inline] ip6_tnl_start_xmit+0x924/0x1dd0 net/ipv6/ip6_tunnel.c:1407 __netdev_start_xmit include/linux/netdevice.h:4314 [inline] netdev_start_xmit include/linux/netdevice.h:4323 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 sch_direct_xmit+0x2d6/0xf50 net/sched/sch_generic.c:332 qdisc_restart net/sched/sch_generic.c:395 [inline] __qdisc_run+0x4d0/0x1630 net/sched/sch_generic.c:403 __dev_xmit_skb net/core/dev.c:3500 [inline] __dev_queue_xmit+0x1516/0x2df0 net/core/dev.c:3810 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0x113d/0x2290 net/ipv6/ip6_output.c:120 ip6_fragment+0x132b/0x32a0 net/ipv6/ip6_output.c:846 ip6_finish_output+0x80b/0xc00 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x205/0x770 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:447 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ip6_xmit+0xdbf/0x20a0 net/ipv6/ip6_output.c:275 sctp_v6_xmit+0x32d/0x640 net/sctp/ipv6.c:229 sctp_packet_transmit+0x1bf6/0x3270 net/sctp/output.c:641 sctp_packet_singleton net/sctp/outqueue.c:791 [inline] sctp_outq_flush_ctrl.constprop.0+0x6d3/0xc40 net/sctp/outqueue.c:922 sctp_outq_flush net/sctp/outqueue.c:1204 [inline] sctp_outq_uncork+0x10b/0x200 net/sctp/outqueue.c:776 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1815 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x4d5/0x4e50 net/sctp/sm_sideeffect.c:1170 sctp_primitive_ASSOCIATE+0x98/0xc0 net/sctp/primitive.c:88 __sctp_connect+0x903/0xd40 net/sctp/socket.c:1244 __sctp_setsockopt_connectx+0x123/0x180 net/sctp/socket.c:1367 sctp_setsockopt_connectx net/sctp/socket.c:1399 [inline] sctp_setsockopt net/sctp/socket.c:4344 [inline] sctp_setsockopt+0x2c88/0x4b60 net/sctp/socket.c:4301 __sys_setsockopt+0x14d/0x240 net/socket.c:1901 __do_sys_setsockopt net/socket.c:1912 [inline] __se_sys_setsockopt net/socket.c:1909 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:1909 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45cb19 Code: 0d 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff201eccc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000505f80 RCX: 000000000045cb19 RDX: 000000000000006e RSI: 0000000000000084 RDI: 000000000000000b RBP: 000000000078bf00 R08: 000000000000001c R09: 0000000000000000 R10: 0000000020000180 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000b26 R14: 00000000004d7d38 R15: 00007ff201ecd6d4 Allocated by task 6453: __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node+0x4c/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:557 [inline] kvmalloc_node+0x61/0xf0 mm/util.c:423 kvmalloc include/linux/mm.h:577 [inline] kvmalloc_array include/linux/mm.h:595 [inline] alloc_fdtable+0xcd/0x280 fs/file.c:115 dup_fd+0x6a2/0xbf0 fs/file.c:310 copy_files kernel/fork.c:1394 [inline] copy_process.part.0+0x1e7c/0x7f40 kernel/fork.c:1885 copy_process kernel/fork.c:1694 [inline] _do_fork+0x22f/0xf30 kernel/fork.c:2207 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2584 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline] rcu_process_callbacks+0x8ff/0x18b0 kernel/rcu/tree.c:2881 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292 The buggy address belongs to the object at ffff88809365b200 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 968 bytes to the right of 2048-byte region [ffff88809365b200, ffff88809365ba00) The buggy address belongs to the page: page:ffffea00024d9680 count:1 mapcount:0 mapping:ffff88812c39cc40 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea0002996c08 ffffea0002a5d388 ffff88812c39cc40 raw: 0000000000000000 ffff88809365a100 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809365bc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809365bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809365bd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88809365be00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809365be80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================