device syz5 entered promiscuous mode
netlink: 152 bytes leftover after parsing attributes in process `syz-executor1'.
==================================================================
BUG: KASAN: use-after-free in __tcp_hdrlen include/linux/tcp.h:35 [inline]
BUG: KASAN: use-after-free in tcp_hdrlen include/linux/tcp.h:40 [inline]
BUG: KASAN: use-after-free in qdisc_pkt_len_init net/core/dev.c:3171 [inline]
BUG: KASAN: use-after-free in __dev_queue_xmit+0x22b6/0x2300 net/core/dev.c:3477
Read of size 2 at addr ffff8801d648a338 by task syz-executor5/9673

CPU: 0 PID: 9673 Comm: syz-executor5 Not tainted 4.15.0-rc6-next-20180105+ #89
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+0x137/0x198 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+0x23b/0x360 mm/kasan/report.c:412
 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:431
 __tcp_hdrlen include/linux/tcp.h:35 [inline]
 tcp_hdrlen include/linux/tcp.h:40 [inline]
 qdisc_pkt_len_init net/core/dev.c:3171 [inline]
 __dev_queue_xmit+0x22b6/0x2300 net/core/dev.c:3477
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3566
 packet_snd net/packet/af_packet.c:2944 [inline]
 packet_sendmsg+0x31d5/0x5720 net/packet/af_packet.c:2969
 sock_sendmsg_nosec net/socket.c:628 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:638
 sock_write_iter+0x21d/0x3a0 net/socket.c:907
 call_write_iter include/linux/fs.h:1775 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x550/0x740 fs/read_write.c:482
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xd4/0x1a0 fs/read_write.c:581
 entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x452ac9
RSP: 002b:00007fb37f476c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000071bf58 RCX: 0000000000452ac9
RDX: 00000000000000a6 RSI: 0000000020bb8f5a RDI: 0000000000000015
RBP: 000000000000054c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f5fc0
R13: 00000000ffffffff R14: 00007fb37f4776d4 R15: 0000000000000007

Allocated by task 3444:
 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:3669 [inline]
 __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3683
 __kmalloc_reserve.isra.39+0x41/0xe0 net/core/skbuff.c:137
 __alloc_skb+0xf0/0x5a0 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:983 [inline]
 alloc_skb_with_frags+0xac/0x500 net/core/skbuff.c:5151
 sock_alloc_send_pskb+0x5ab/0x730 net/core/sock.c:2088
 unix_dgram_sendmsg+0x372/0x1050 net/unix/af_unix.c:1682
 sock_sendmsg_nosec net/socket.c:628 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:638
 SYSC_sendto+0x2e0/0x360 net/socket.c:1719
 SyS_sendto+0x40/0x50 net/socket.c:1687
 entry_SYSCALL_64_fastpath+0x23/0x9a

Freed by task 1774:
 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:3485 [inline]
 kfree+0xd9/0x260 mm/slab.c:3800
 skb_free_head+0x74/0xb0 net/core/skbuff.c:550
 skb_release_data+0x442/0x5e0 net/core/skbuff.c:570
 skb_release_all+0x4a/0x60 net/core/skbuff.c:627
 __kfree_skb net/core/skbuff.c:641 [inline]
 consume_skb+0x9e/0x2e0 net/core/skbuff.c:701
 skb_free_datagram+0x1a/0xe0 net/core/datagram.c:329
 unix_dgram_recvmsg+0x866/0xde0 net/unix/af_unix.c:2184
 sock_recvmsg_nosec net/socket.c:801 [inline]
 sock_recvmsg+0xc9/0x110 net/socket.c:808
 SYSC_recvfrom+0x1fc/0x350 net/socket.c:1771
 SyS_recvfrom+0x40/0x50 net/socket.c:1743
 entry_SYSCALL_64_fastpath+0x23/0x9a

The buggy address belongs to the object at ffff8801d648a280
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 184 bytes inside of
 512-byte region [ffff8801d648a280, ffff8801d648a480)
The buggy address belongs to the page:
page:ffffea0007592280 count:1 mapcount:0 mapping:ffff8801d648a000 index:0xffff8801d648a500
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801d648a000 ffff8801d648a500 0000000100000004
raw: ffffea00075af3e0 ffffea00074de3a0 ffff8801db000940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d648a200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801d648a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801d648a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff8801d648a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801d648a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================