syzbot

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WARNING: CPU: 1 PID: 2227 at net/ipv4/tcp.c:1737 tcp_recvmsg+0x209b/0x2d10 net/ipv4/tcp.c:1737()
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 2227 Comm: syz-executor958 Not tainted 4.4.174+ #4
 0000000000000000 4af592cdacfb77d0 ffff8801d2f67808 ffffffff81aad1a1
 0000000000000000 ffffffff82835ee0 ffffffff82a85940 00000000000006c9
 ffffffff823f4dab ffff8801d2f678e8 ffffffff813a48c2 0000000041b58ab3
Call Trace:
 [<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff813a48c2>] panic+0x1b9/0x37b kernel/panic.c:112
 [<ffffffff813a4ab9>] warn_slowpath_common kernel/panic.c:455 [inline]
 [<ffffffff813a4ab9>] warn_slowpath_common.cold+0x20/0x20 kernel/panic.c:435
 [<ffffffff810d3aaa>] warn_slowpath_null+0x2a/0x30 kernel/panic.c:492
 [<ffffffff823f4dab>] tcp_recvmsg+0x209b/0x2d10 net/ipv4/tcp.c:1737
 [<ffffffff824a86ae>] inet_recvmsg+0x23e/0x4d0 net/ipv4/af_inet.c:786
 [<ffffffff821d8d9f>] sock_recvmsg_nosec net/socket.c:740 [inline]
 [<ffffffff821d8d9f>] sock_recvmsg net/socket.c:748 [inline]
 [<ffffffff821d8d9f>] sock_recvmsg+0x8f/0xc0 net/socket.c:743
 [<ffffffff821da5e7>] ___sys_recvmsg+0x257/0x530 net/socket.c:2129
 [<ffffffff821dd5b5>] __sys_recvmsg+0xc5/0x160 net/socket.c:2175
 [<ffffffff821dd67d>] SYSC_recvmsg net/socket.c:2187 [inline]
 [<ffffffff821dd67d>] SyS_recvmsg+0x2d/0x50 net/socket.c:2182
 [<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
Kernel Offset: disabled
Rebooting in 86400 seconds..