kernel BUG at include/linux/mm.h:LINE! (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    7170e6045a6a strparser: Add __strp_unpause and use it in k..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=114236af800000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a601a80fec461d44
dashboard link: https://syzkaller.appspot.com/bug?extid=3225ce21c0e9929bb9cf
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=10f44fdf800000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=110f636f800000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3225ce21c0e9929bb9cf@xxxxxxxxxxxxxxxxxxxxxxxxx

flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffff80
raw: ffffea0006b29220 ffff88021fffac18 0000000000000003 0000000000000000
page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) <= 0)
------------[ cut here ]------------
kernel BUG at include/linux/mm.h:853!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4545 Comm: syz-executor492 Not tainted 4.17.0-rc7+ #82
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:get_page include/linux/mm.h:853 [inline]
RIP: 0010:do_tcp_sendpages+0x1879/0x1e60 net/ipv4/tcp.c:1002
RSP: 0018:ffff8801c2a06f88 EFLAGS: 00010203
RAX: 0000000000000000 RBX: ffff8801d972d580 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81a66c25 RDI: ffffed0038540de0
RBP: ffff8801c2a071e8 R08: ffff8801b11d2480 R09: 0000000000000006
R10: ffff8801b11d2480 R11: 0000000000000000 R12: 000000000000301d
R13: ffffea0006b2621c R14: ffff8801ae5a6040 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020008000 CR3: 0000000008c6a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tls_push_sg+0x25b/0x860 net/tls/tls_main.c:126
 tls_push_record+0xae5/0x13e0 net/tls/tls_sw.c:266
 tls_sw_push_pending_record+0x22/0x30 net/tls/tls_sw.c:276
 tls_handle_open_record net/tls/tls_main.c:164 [inline]
 tls_sk_proto_close+0x734/0xad0 net/tls/tls_main.c:264
 inet_release+0x104/0x1f0 net/ipv4/af_inet.c:427
 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:459
 sock_release+0x96/0x1b0 net/socket.c:594
 sock_close+0x16/0x20 net/socket.c:1149
 __fput+0x34d/0x890 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x1e4/0x290 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x1aee/0x2730 kernel/exit.c:865
 do_group_exit+0x16f/0x430 kernel/exit.c:968
 __do_sys_exit_group kernel/exit.c:979 [inline]
 __se_sys_exit_group kernel/exit.c:977 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43f368
RSP: 002b:00007ffd03500578 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f368
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004bf448 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000
Code: ff ff 41 89 86 cc 08 00 00 e8 e4 07 05 00 e9 2c eb ff ff e8 ca 4b 27  
fb 48 8b bd b8 fd ff ff 48 c7 c6 40 0c 54 88 e8 77 72 54 fb <0f> 0b 48 89  
85 b8 fd ff ff e8 a9 4b 27 fb 48 8b 85 b8 fd ff ff
RIP: get_page include/linux/mm.h:853 [inline] RSP: ffff8801c2a06f88
RIP: do_tcp_sendpages+0x1879/0x1e60 net/ipv4/tcp.c:1002 RSP:  
ffff8801c2a06f88
---[ end trace 500a6e4fab99629c ]---


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