------------[ cut here ]------------
WARNING: CPU: 1 PID: 6490 at net/core/skbuff.c:4398 skb_try_coalesce+0xeb7/0x1260 net/core/skbuff.c:4398
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 6490 Comm: syz-executor.3 Not tainted 4.9.194+ #0
 ffff8801c8c17030 ffffffff81b67001 0000000000000000 ffffffff82a3b3c0
 00000000ffffffff 0000000000000001 0000000000000009 ffff8801c8c17110
 ffffffff813fef3a 0000000041b58ab3 ffffffff82e32f55 ffffffff813fed61
Call Trace:
 [<00000000af991fa2>] __dump_stack lib/dump_stack.c:15 [inline]
 [<00000000af991fa2>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<0000000010faddc0>] panic+0x1d9/0x3bd kernel/panic.c:180
 [<0000000086bd86c8>] __warn.cold+0x2f/0x2f kernel/panic.c:546
 [<0000000086c8397f>] warn_slowpath_null+0x2d/0x40 kernel/panic.c:589
 [<00000000092f2e1d>] skb_try_coalesce+0xeb7/0x1260 net/core/skbuff.c:4398
 [<00000000f184b9a7>] tcp_try_coalesce+0x173/0x4e0 net/ipv4/tcp_input.c:4378
 [<00000000b0eb815d>] tcp_queue_rcv+0x129/0x5a0 net/ipv4/tcp_input.c:4630
 [<0000000089b292ec>] tcp_data_queue+0x600/0x3810 net/ipv4/tcp_input.c:4739
 [<000000006b6c13f9>] tcp_rcv_established+0x55a/0x20b0 net/ipv4/tcp_input.c:5620
 [<000000002a423c2f>] tcp_v6_do_rcv+0xcd9/0x10f0 net/ipv6/tcp_ipv6.c:1283
 [<0000000078e81148>] sk_backlog_rcv include/net/sock.h:881 [inline]
 [<0000000078e81148>] __release_sock+0x138/0x390 net/core/sock.c:2060
 [<000000005d653143>] release_sock+0x59/0x1c0 net/core/sock.c:2524
 [<00000000be162f99>] tcp_sendpage net/ipv4/tcp.c:1034 [inline]
 [<00000000be162f99>] tcp_sendpage+0x6b4/0x18f0 net/ipv4/tcp.c:1019
 [<00000000ba70c2b7>] inet_sendpage+0x223/0x520 net/ipv4/af_inet.c:783
 [<00000000599a4ad3>] kernel_sendpage+0x95/0xf0 net/socket.c:3326
 [<0000000007ae7634>] sock_sendpage+0x8b/0xc0 net/socket.c:803
 [<000000009b6e8600>] pipe_to_sendpage+0x28d/0x3d0 fs/splice.c:470
 [<000000003c673757>] splice_from_pipe_feed fs/splice.c:521 [inline]
 [<000000003c673757>] __splice_from_pipe+0x351/0x790 fs/splice.c:645
 [<000000006682e30a>] splice_from_pipe+0x108/0x170 fs/splice.c:680
 [<000000005e9449a6>] generic_splice_sendpage+0x3c/0x50 fs/splice.c:851
 [<000000004d9b94d0>] do_splice_from fs/splice.c:870 [inline]
 [<000000004d9b94d0>] direct_splice_actor+0x126/0x1a0 fs/splice.c:1037
 [<000000002899d6d4>] splice_direct_to_actor+0x2c8/0x820 fs/splice.c:992
 [<0000000081d048f1>] do_splice_direct+0x1a5/0x260 fs/splice.c:1080
 [<00000000bf76fdfd>] do_sendfile+0x503/0xc00 fs/read_write.c:1402
 [<00000000199537e3>] SYSC_sendfile64 fs/read_write.c:1463 [inline]
 [<00000000199537e3>] SyS_sendfile64+0x145/0x160 fs/read_write.c:1449
 [<00000000cc156311>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
 [<00000000c1c7585a>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Kernel Offset: disabled
Rebooting in 86400 seconds..