IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
==================================================================
BUG: KASAN: out-of-bounds in napi_frags_skb net/core/dev.c:5758 [inline]
BUG: KASAN: out-of-bounds in napi_gro_frags+0x880/0x940 net/core/dev.c:5765
Read of size 2 at addr ffff888094e485d6 by task syz-executor.2/7151

CPU: 0 PID: 7151 Comm: syz-executor.2 Not tainted 4.20.0-rc2+ #1
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+0x16b/0x224 lib/dump_stack.c:113
 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:443
 napi_frags_skb net/core/dev.c:5758 [inline]
 napi_gro_frags+0x880/0x940 net/core/dev.c:5765
 tun_get_user+0x2208/0x3460 drivers/net/tun.c:1952
 tun_chr_write_iter+0xaf/0x150 drivers/net/tun.c:1997
 call_write_iter include/linux/fs.h:1857 [inline]
 do_iter_readv_writev+0x4ae/0x960 fs/read_write.c:680
 do_iter_write+0x12a/0x510 fs/read_write.c:959
 vfs_writev+0x16f/0x2d0 fs/read_write.c:1004
 do_writev+0xda/0x260 fs/read_write.c:1039
 __do_sys_writev fs/read_write.c:1112 [inline]
 __se_sys_writev fs/read_write.c:1109 [inline]
 __x64_sys_writev+0x70/0xb0 fs/read_write.c:1109
 do_syscall_64+0xd0/0x4d0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459131
Code: 75 14 b8 14 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 b9 fb ff c3 48 83 ec 08 e8 fa 2c 00 00 48 89 04 24 b8 14 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 43 2d 00 00 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fa44f7bfba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000020000d85 RCX: 0000000000459131
RDX: 0000000000000003 RSI: 00007fa44f7bfc00 RDI: 00000000000000f0
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 00007fa44f7c09d0 R11: 0000000000000293 R12: 00007fa44f7c06d4
R13: 00000000004c7d21 R14: 00000000004de160 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea0002539200 count:1 mapcount:-512 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 dead000000000100 dead000000000200 0000000000000000
raw: 0000000000000000 0000000000000000 00000001fffffdff ffff888090388740
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff888090388740

Memory state around the buggy address:
 ffff888094e48480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888094e48500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888094e48580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                    ^
 ffff888094e48600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888094e48680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================