[syzbot] [mptcp?] WARNING in mptcp_check_listen_stop

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 2513974cc3e1 Merge branch 'stmmac-bug-fixes'
git tree: net
console output: https://syzkaller.appspot.com/x/log.txt?x=1237863ee80000
kernel config: https://syzkaller.appspot.com/x/.config?x=b50bd31249191be8
dashboard link: https://syzkaller.appspot.com/bug?extid=5a01c3a666e726bc8752
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fbf7f04433a8/disk-2513974c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f839967d18d6/vmlinux-2513974c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/10f6c15a1f15/bzImage-2513974c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5a01c3...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 27574 at net/mptcp/protocol.c:2999 mptcp_check_listen_stop.part.0+0x17b/0x240 net/mptcp/protocol.c:2999
Modules linked in:
CPU: 0 PID: 27574 Comm: syz-executor.2 Not tainted 6.7.0-rc4-syzkaller-00167-g2513974cc3e1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:mptcp_check_listen_stop.part.0+0x17b/0x240 net/mptcp/protocol.c:2999
Code: 00 00 00 0f b6 45 12 88 44 24 20 44 0f b6 6c 24 20 bf 0a 00 00 00 44 89 ee e8 c1 66 24 f7 41 80 fd 0a 74 2b e8 86 6b 24 f7 90 <0f> 0b 90 e8 7d 6b 24 f7 48 b8 00 00 00 00 00 fc ff df 49 c7 04 04
RSP: 0018:ffffc9001500fce0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88803f651880 RCX: ffffffff8a63221f
RDX: ffff8880545f1dc0 RSI: ffffffff8a63222a RDI: 0000000000000001
RBP: ffff888025953400 R08: 0000000000000001 R09: 000000000000000a
R10: 0000000000000007 R11: 0000000000000002 R12: 1ffff92002a01f9c
R13: 0000000000000007 R14: ffff88803f651892 R15: 000000000000000a
FS: 0000555556b7b480(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31f25000 CR3: 0000000027e0c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
mptcp_check_listen_stop net/mptcp/protocol.c:3032 [inline]
__mptcp_close+0x888/0xa10 net/mptcp/protocol.c:3020
mptcp_close+0x28/0xf0 net/mptcp/protocol.c:3087
inet_release+0x132/0x270 net/ipv4/af_inet.c:433
inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:485
__sock_release+0xae/0x260 net/socket.c:659
sock_close+0x1c/0x20 net/socket.c:1419
__fput+0x270/0xbb0 fs/file_table.c:394
__fput_sync+0x47/0x50 fs/file_table.c:475
__do_sys_close fs/open.c:1590 [inline]
__se_sys_close fs/open.c:1575 [inline]
__x64_sys_close+0x87/0xf0 fs/open.c:1575
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f398e47ba9a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007ffcd1957d90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f398e47ba9a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f398e59d980 R08: 0000001b32320000 R09: 0000000000000033
R10: 000000008a82179f R11: 0000000000000293 R12: 00000000002addf7
R13: ffffffffffffffff R14: 00007f398e000000 R15: 00000000002adab6
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 2513974cc3e1 Merge branch 'stmmac-bug-fixes'
git tree: net

console+strace: https://syzkaller.appspot.com/x/log.txt?x=116337fae80000

kernel config: https://syzkaller.appspot.com/x/.config?x=b50bd31249191be8
dashboard link: https://syzkaller.appspot.com/bug?extid=5a01c3a666e726bc8752
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1119061ee80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=110ca006e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fbf7f04433a8/disk-2513974c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f839967d18d6/vmlinux-2513974c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/10f6c15a1f15/bzImage-2513974c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5a01c3...@syzkaller.appspotmail.com

------------[ cut here ]------------

WARNING: CPU: 0 PID: 5075 at net/mptcp/protocol.c:2999 mptcp_check_listen_stop.part.0+0x17b/0x240 net/mptcp/protocol.c:2999
Modules linked in:
CPU: 0 PID: 5075 Comm: syz-executor686 Not tainted 6.7.0-rc4-syzkaller-00167-g2513974cc3e1 #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:mptcp_check_listen_stop.part.0+0x17b/0x240 net/mptcp/protocol.c:2999
Code: 00 00 00 0f b6 45 12 88 44 24 20 44 0f b6 6c 24 20 bf 0a 00 00 00 44 89 ee e8 c1 66 24 f7 41 80 fd 0a 74 2b e8 86 6b 24 f7 90 <0f> 0b 90 e8 7d 6b 24 f7 48 b8 00 00 00 00 00 fc ff df 49 c7 04 04

RSP: 0018:ffffc900039efb50 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff8880187b8000 RCX: ffffffff8a63221f
RDX: ffff8880137a0000 RSI: ffffffff8a63222a RDI: 0000000000000001
RBP: ffff888018b30000 R08: 0000000000000001 R09: 000000000000000a
R10: 0000000000000007 R11: 0000000000000002 R12: 1ffff9200073df6a
R13: 0000000000000007 R14: ffff8880187b8012 R15: 000000000000000a
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f8ccb1dd0f0 CR3: 000000000cd77000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
mptcp_check_listen_stop net/mptcp/protocol.c:3032 [inline]
__mptcp_close+0x888/0xa10 net/mptcp/protocol.c:3020
mptcp_close+0x28/0xf0 net/mptcp/protocol.c:3087
inet_release+0x132/0x270 net/ipv4/af_inet.c:433
inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:485
__sock_release+0xae/0x260 net/socket.c:659
sock_close+0x1c/0x20 net/socket.c:1419
__fput+0x270/0xbb0 fs/file_table.c:394

task_work_run+0x14d/0x240 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xa92/0x2ae0 kernel/exit.c:871
do_group_exit+0xd4/0x2a0 kernel/exit.c:1021
__do_sys_exit_group kernel/exit.c:1032 [inline]
__se_sys_exit_group kernel/exit.c:1030 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1030

do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

RIP: 0033:0x7f8ccb161d79
Code: Unable to access opcode bytes at 0x7f8ccb161d4f.
RSP: 002b:00007ffce6b9dbd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8ccb161d79
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007f8ccb1dc290 R08: ffffffffffffffb8 R09: 00007ffce6b9ddf8
R10: 00007ffce6b9ddf8 R11: 0000000000000246 R12: 00007f8ccb1dc290
R13: 0000000000000000 R14: 00007f8ccb1dcce0 R15: 00007f8ccb133b40
</TASK>


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[Paolo Abeni]

On Wed, 2023-12-13 at 10:53 -0800, syzbot wrote:
> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 2513974cc3e1 Merge branch 'stmmac-bug-fixes'
> git tree: net
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=116337fae80000
> kernel config: https://syzkaller.appspot.com/x/.config?x=b50bd31249191be8
> dashboard link: https://syzkaller.appspot.com/bug?extid=5a01c3a666e726bc8752
> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1119061ee80000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=110ca006e80000

It looks like tcp_diag_destroy is closing the listener subflow, while
the mptcp stack is not expecting anyone to touch it while in listener
status. I guess we can relax the mptcp_check_listen_stop checks.

/P

[syzbot]

syzbot has bisected this issue to:

commit 57fc0f1ceaa4016354cf6f88533e20b56190e41a
Author: Paolo Abeni <pab...@redhat.com>
Date: Tue Jun 20 16:24:23 2023 +0000

mptcp: ensure listener is unhashed before updating the sk status

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1279cb71e80000
start commit: 2513974cc3e1 Merge branch 'stmmac-bug-fixes'
git tree: net
final oops: https://syzkaller.appspot.com/x/report.txt?x=1179cb71e80000
console output: https://syzkaller.appspot.com/x/log.txt?x=1679cb71e80000

kernel config: https://syzkaller.appspot.com/x/.config?x=b50bd31249191be8
dashboard link: https://syzkaller.appspot.com/bug?extid=5a01c3a666e726bc8752

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1119061ee80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=110ca006e80000

Reported-by: syzbot+5a01c3...@syzkaller.appspotmail.com
Fixes: 57fc0f1ceaa4 ("mptcp: ensure listener is unhashed before updating the sk status")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection