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BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0xfac/0x1120 net/ipv4/ip_options.c:196
Write of size 1 at addr ffff888095807093 by task syz-executor.5/9089

CPU: 1 PID: 9089 Comm: syz-executor.5 Not tainted 5.1.0-rc5+ #146
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:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_store1_noabort+0x17/0x20 mm/kasan/generic_report.c:134
 __ip_options_echo+0xfac/0x1120 net/ipv4/ip_options.c:196
 __icmp_send+0x725/0x1400 net/ipv4/icmp.c:695
 ipv4_link_failure+0x29f/0x550 net/ipv4/route.c:1219
 dst_link_failure include/net/dst.h:416 [inline]
 vti6_xmit net/ipv6/ip6_vti.c:514 [inline]
 vti6_tnl_xmit+0x10d4/0x1c0c net/ipv6/ip6_vti.c:553
 __netdev_start_xmit include/linux/netdevice.h:4431 [inline]
 netdev_start_xmit include/linux/netdevice.h:4445 [inline]
 xmit_one net/core/dev.c:3292 [inline]
 dev_hard_start_xmit+0x18f/0x960 net/core/dev.c:3308
 __dev_queue_xmit+0x2a9d/0x36c0 net/core/dev.c:3881
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3914
 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527
 neigh_output include/net/neighbour.h:511 [inline]
 ip_finish_output2+0x8ff/0x24e0 net/ipv4/ip_output.c:227
 ip_finish_output+0x734/0xd50 net/ipv4/ip_output.c:314
 NF_HOOK_COND include/linux/netfilter.h:285 [inline]
 ip_output+0x21f/0x670 net/ipv4/ip_output.c:402
 dst_output include/net/dst.h:433 [inline]
 NF_HOOK include/linux/netfilter.h:296 [inline]
 raw_send_hdrinc net/ipv4/raw.c:432 [inline]
 raw_sendmsg+0x1d2b/0x2f20 net/ipv4/raw.c:663
 inet_sendmsg+0x147/0x5e0 net/ipv4/af_inet.c:802
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 sock_write_iter+0x27c/0x3e0 net/socket.c:988
 call_write_iter include/linux/fs.h:1866 [inline]
 new_sync_write+0x4c7/0x760 fs/read_write.c:474
 __vfs_write+0xe4/0x110 fs/read_write.c:487
 vfs_write+0x20c/0x580 fs/read_write.c:549
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458c29
Code: ad b8 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdbe9862d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29
RDX: 0000000000000014 RSI: 00000000200002c0 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001d27914
R13: 00000000004c8623 R14: 00000000004ded68 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea00025601c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 ffffffff02560101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888095806f80: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2
 ffff888095807000: f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888095807080: 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff888095807100: 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00 00 00 00
 ffff888095807180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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