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WARNING: CPU: 0 PID: 9749 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x674/0x830 net/ipv4/af_inet.c:156
Modules linked in:
CPU: 0 PID: 9749 Comm: kworker/0:4 Not tainted 5.11.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events mptcp_worker
RIP: 0010:inet_sock_destruct+0x674/0x830 net/ipv4/af_inet.c:156
Code: 4c 89 e7 e8 6e 1f 6b ff e9 09 fd ff ff e8 24 f2 ee f9 0f 0b e9 43 fe ff ff e8 18 f2 ee f9 0f 0b e9 94 fe ff ff e8 0c f2 ee f9 <0f> 0b e9 cf fe ff ff e8 00 f2 ee f9 0f 0b e9 0a ff ff ff e8 d4 ad
RSP: 0000:ffffc90015d0fa38 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 000000000016d520 RCX: 0000000000000000
RDX: ffff88805a261bc0 RSI: ffffffff8783d674 RDI: 0000000000000003
RBP: ffff888021c0e46c R08: 0000000000000000 R09: ffff888021c0e46f
R10: ffffffff8783d542 R11: 0000000000000000 R12: ffff888021c0e200
R13: ffff888021c0e350 R14: 0000000000000003 R15: ffff888021c0e638
FS:  0000000000000000(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4e99ba0eb0 CR3: 00000000283e5000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __sk_destruct+0x4b/0x900 net/core/sock.c:1778
 sk_destruct+0xbd/0xe0 net/core/sock.c:1822
 __sk_free+0xef/0x3d0 net/core/sock.c:1833
 sk_free+0x78/0xa0 net/core/sock.c:1844
 sock_put include/net/sock.h:1797 [inline]
 __mptcp_close_ssk+0x36d/0x460 net/mptcp/protocol.c:2154
 __mptcp_destroy_sock+0x349/0x790 net/mptcp/protocol.c:2553
 mptcp_worker+0x7da/0x1960 net/mptcp/protocol.c:2295
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296