==================================================================
BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry+0x2de/0x320 fs/ext4/dir.c:69
Read of size 2 at addr ffff8801d032a002 by task syz-executor5/7211

CPU: 1 PID: 7211 Comm: syz-executor5 Not tainted 4.16.0-rc7+ #9
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:431
 __ext4_check_dir_entry+0x2de/0x320 fs/ext4/dir.c:69
 ext4_readdir+0xd00/0x3600 fs/ext4/dir.c:237
 iterate_dir+0x1ca/0x530 fs/readdir.c:51
 SYSC_getdents64 fs/readdir.c:314 [inline]
 SyS_getdents64+0x221/0x420 fs/readdir.c:295
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x454e79
RSP: 002b:00007ff7bb679c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007ff7bb67a6d4 RCX: 0000000000454e79
RDX: 00000000200015fc RSI: 0000000020001540 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000a9 R14: 00000000006f3078 R15: 0000000000000000

Allocated by task 6196:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552
 __do_kmalloc_node mm/slab.c:3670 [inline]
 __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3684
 __kmalloc_reserve.isra.39+0x41/0xd0 net/core/skbuff.c:137
 __alloc_skb+0x13b/0x780 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:983 [inline]
 ndisc_alloc_skb+0x138/0x330 net/ipv6/ndisc.c:403
 ndisc_send_rs+0x2f4/0x670 net/ipv6/ndisc.c:669
 addrconf_rs_timer+0x363/0x6b0 net/ipv6/addrconf.c:3769
 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666
 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285

Freed by task 6196:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3486 [inline]
 kfree+0xd9/0x260 mm/slab.c:3801
 skb_free_head+0x74/0xb0 net/core/skbuff.c:550
 skb_release_data+0x58c/0x790 net/core/skbuff.c:570
 skb_release_all+0x4a/0x60 net/core/skbuff.c:627
 __kfree_skb net/core/skbuff.c:641 [inline]
 kfree_skb+0x15d/0x4c0 net/core/skbuff.c:659
 ip_tunnel_xmit+0x710/0x3550 net/ipv4/ip_tunnel.c:804
 __gre_xmit+0x546/0x8b0 net/ipv4/ip_gre.c:449
 erspan_xmit+0x779/0x22a0 net/ipv4/ip_gre.c:728
 __netdev_start_xmit include/linux/netdevice.h:4066 [inline]
 netdev_start_xmit include/linux/netdevice.h:4075 [inline]
 xmit_one net/core/dev.c:3026 [inline]
 dev_hard_start_xmit+0x24e/0xac0 net/core/dev.c:3042
 sch_direct_xmit+0x40d/0x1140 net/sched/sch_generic.c:327
 qdisc_restart net/sched/sch_generic.c:399 [inline]
 __qdisc_run+0x676/0x19b0 net/sched/sch_generic.c:410
 __dev_xmit_skb net/core/dev.c:3217 [inline]
 __dev_queue_xmit+0xb8b/0x2fc0 net/core/dev.c:3525
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3590
 neigh_hh_output include/net/neighbour.h:472 [inline]
 neigh_output include/net/neighbour.h:480 [inline]
 ip6_finish_output2+0x1492/0x23a0 net/ipv6/ip6_output.c:120
 ip6_finish_output+0x69b/0xaf0 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:277 [inline]
 ip6_output+0x1eb/0x840 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:443 [inline]
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ndisc_send_skb+0xac4/0x1370 net/ipv6/ndisc.c:491
 ndisc_send_rs+0x126/0x670 net/ipv6/ndisc.c:685
 addrconf_rs_timer+0x363/0x6b0 net/ipv6/addrconf.c:3769
 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666
 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285

The buggy address belongs to the object at ffff8801d032a040
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 62 bytes to the left of
 1024-byte region [ffff8801d032a040, ffff8801d032a440)
The buggy address belongs to the page:
page:ffffea000740ca80 count:1 mapcount:0 mapping:ffff8801d032a040 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801d032a040 0000000000000000 0000000100000007
raw: ffffea00074149a0 ffffea0006a81220 ffff8801dac00ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d0329f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801d0329f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801d032a000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                   ^
 ffff8801d032a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801d032a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================