syzbot

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WARNING: CPU: 1 PID: 14299 at include/net/mptcp.h:102 mptcp_skb_ext_move include/net/mptcp.h:102 [inline]
WARNING: CPU: 1 PID: 14299 at include/net/mptcp.h:102 tcp_collapse+0x1316/0x16f0 net/ipv4/tcp_input.c:5138
Modules linked in:
CPU: 1 PID: 14299 Comm: syz-executor.5 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mptcp_skb_ext_move include/net/mptcp.h:102 [inline]
RIP: 0010:tcp_collapse+0x1316/0x16f0 net/ipv4/tcp_input.c:5138
Code: e8 8f 52 ff f9 8b 1c 24 31 ff 2b 9c 24 68 01 00 00 89 de e8 cc 4a ff f9 85 db 0f 88 fd f2 ff ff e9 72 fc ff ff e8 6a 52 ff f9 <0f> 0b 48 8d 85 d8 00 00 00 48 b9 00 00 00 00 00 fc ff df 48 c1 e8
RSP: 0018:ffffc900022ff3c8 EFLAGS: 00010246
RAX: 0000000000040000 RBX: 0000000000000008 RCX: ffffc900162f1000
RDX: 0000000000040000 RSI: ffffffff8770c766 RDI: 0000000000000001
RBP: ffff8880690dba00 R08: 0000000000000001 R09: ffff888028da998b
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88805a0445e0
R13: ffff8880690dba7f R14: 0000000000000ec0 R15: ffff88805a04465f
FS:  00007f015ba44700(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a19d23fc30 CR3: 000000007266e000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcp_prune_queue net/ipv4/tcp_input.c:5295 [inline]
 tcp_try_rmem_schedule+0xbc9/0x16e0 net/ipv4/tcp_input.c:4680
 tcp_data_queue+0x17bd/0x4b10 net/ipv4/tcp_input.c:4949
 tcp_rcv_established+0x841/0x1eb0 net/ipv4/tcp_input.c:5867
 tcp_v4_do_rcv+0x5d1/0x870 net/ipv4/tcp_ipv4.c:1652
 sk_backlog_rcv include/net/sock.h:1010 [inline]
 __release_sock+0x134/0x3a0 net/core/sock.c:2523
 release_sock+0x54/0x1b0 net/core/sock.c:3053
 mptcp_sendmsg+0xf75/0x1970 net/mptcp/protocol.c:1319
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 sock_write_iter+0x289/0x3c0 net/socket.c:998
 call_write_iter include/linux/fs.h:1887 [inline]
 do_iter_readv_writev+0x46f/0x740 fs/read_write.c:740
 do_iter_write+0x188/0x670 fs/read_write.c:866
 vfs_writev+0x1aa/0x2e0 fs/read_write.c:939
 do_writev+0x27f/0x300 fs/read_write.c:982
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45deb9
Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f015ba43c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 000000000003b980 RCX: 000000000045deb9
RDX: 0000000000000004 RSI: 0000000020000440 RDI: 0000000000000003
RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 00007ffe4edb697f R14: 00007f015ba449c0 R15: 000000000118bf2c