================================================================== BUG: KASAN: slab-out-of-bounds in _decode_session6+0xf56/0x1370 net/ipv6/xfrm6_policy.c:137 Read of size 1 at addr ffff8880318ebdb9 by task kworker/u4:14/13746 CPU: 0 PID: 13746 Comm: kworker/u4:14 Not tainted 4.19.188-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'. Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 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 include/net/xfrm.h:1238 [inline] vti_tunnel_xmit+0x279/0x1850 net/ipv4/ip_vti.c:326 __netdev_start_xmit include/linux/netdevice.h:4345 [inline] netdev_start_xmit include/linux/netdevice.h:4359 [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+0x4d0/0x1640 net/sched/sch_generic.c:403 __dev_xmit_skb net/core/dev.c:3500 [inline] __dev_queue_xmit+0x1518/0x2e00 net/core/dev.c:3807 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0x113d/0x2290 net/ipv6/ip6_output.c:120 ip6_finish_output+0x795/0xe50 net/ipv6/ip6_output.c:192 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x205/0x770 net/ipv6/ip6_output.c:209 dst_output include/net/dst.h:455 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ndisc_send_skb+0xa24/0x1720 net/ipv6/ndisc.c:491 ndisc_send_rs+0x131/0x690 net/ipv6/ndisc.c:685 addrconf_rs_timer+0x384/0x6a0 net/ipv6/addrconf.c:3835 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:535 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] RIP: 0010:lock_acquire+0x1ec/0x3c0 kernel/locking/lockdep.c:3910 Code: 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 b7 01 00 00 48 83 3d 69 4e a6 08 00 0f 84 2a 01 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 65 8b RSP: 0018:ffff8880347d7c58 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3049 RBX: ffff88809fb545c0 RCX: 9c1f49bc7908dbe0 RDX: dffffc0000000000 RSI: 0000000005498b2d RDI: 0000000000000286 RBP: ffffffff89f85ea0 R08: 000000005f736fb7 R09: 0000000000000002 R10: ffff88809fb54e98 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:627 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:419 [inline] batadv_nc_worker+0x12d/0xd50 net/batman-adv/network-coding.c:730 process_one_work+0x864/0x1570 kernel/workqueue.c:2152 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 6682: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] snmp6_alloc_dev net/ipv6/addrconf.c:351 [inline] ipv6_add_dev+0x4f8/0x10b0 net/ipv6/addrconf.c:400 addrconf_notify+0x6a3/0x21f0 net/ipv6/addrconf.c:3447 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93 call_netdevice_notifiers net/core/dev.c:1762 [inline] register_netdevice+0xdd2/0x10f0 net/core/dev.c:8753 veth_newlink+0x4dd/0x930 drivers/net/veth.c:1169 rtnl_newlink+0x1030/0x15c0 net/core/rtnetlink.c:3141 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:632 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115 __sys_sendmsg net/socket.c:2153 [inline] __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8880318ea000 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 3513 bytes to the right of 4096-byte region [ffff8880318ea000, ffff8880318eb000) The buggy address belongs to the page: page:ffffea0000c63a80 count:1 mapcount:0 mapping:ffff88813bff0dc0 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0002710c88 ffffea0000a3b588 ffff88813bff0dc0 raw: 0000000000000000 ffff8880318ea000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880318ebc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880318ebd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880318ebd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880318ebe00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880318ebe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================