Subject: [syzbot] [mptcp?] WARNING in __mptcp_clean_una

From: syzbot <[email-masked]>
Date: Fri, 16 Feb 2024 09:37:23 -0800

Hello,

syzbot found the following issue on:

HEAD commit:    4f5e5092fdbf Merge tag 'net-6.8-rc5' of git://git.kernel.o..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=129f6398180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1d7c92dd8d5c7a1e
dashboard link: https://syzkaller.appspot.com/bug?extid=5b3e7c7a0b77f0c03b0d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14fc9c8a180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17d0cc1c180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d430539932db/disk-4f5e5092.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6369586e33b7/vmlinux-4f5e5092.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9c1e38f80254/bzImage-4f5e5092.xz

The issue was bisected to:

commit 3f83d8a77eeeb47011b990fd766a421ee64f1d73
Author: Paolo Abeni <[email-masked]>
Date:   Thu Feb 8 18:03:51 2024 +0000

    mptcp: fix more tx path fields initialization

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=160a83a4180000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=150a83a4180000
console output: https://syzkaller.appspot.com/x/log.txt?x=110a83a4180000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]
Fixes: 3f83d8a77eee ("mptcp: fix more tx path fields initialization")

------------[ cut here ]------------
WARNING: CPU: 1 PID: 27 at net/mptcp/protocol.c:1001 __mptcp_clean_una+0xb89/0xd70 net/mptcp/protocol.c:1001
Modules linked in:
CPU: 1 PID: 27 Comm: kworker/1:1 Not tainted 6.8.0-rc4-syzkaller-00180-g4f5e5092fdbf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: events mptcp_worker
RIP: 0010:__mptcp_clean_una+0xb89/0xd70 net/mptcp/protocol.c:1001
Code: 8d 0d a5 f6 e9 7d fc ff ff 44 89 f1 80 e1 07 38 c1 0f 8c 87 fc ff ff 4c 89 f7 e8 72 0d a5 f6 e9 7a fc ff ff e8 98 f0 42 f6 90 <0f> 0b 90 49 bc 00 00 00 00 00 fc ff df e9 29 f7 ff ff 44 89 f1 80
RSP: 0018:ffffc90000a2f860 EFLAGS: 00010293
RAX: ffffffff8b507ba8 RBX: ffff888024ee3ab8 RCX: ffff8880192e9dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a2f950 R08: ffffffff8b507228 R09: fffff52000145f24
R10: dffffc0000000000 R11: fffff52000145f24 R12: dffffc0000000000
R13: 1ffff11004a6e000 R14: 0000000000000000 R15: ffff888025370000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8a82c561d0 CR3: 000000007d8b6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __mptcp_clean_una_wakeup+0x7f/0x340 net/mptcp/protocol.c:1049
 mptcp_clean_una_wakeup net/mptcp/protocol.c:1056 [inline]
 __mptcp_retrans+0xbf/0xb20 net/mptcp/protocol.c:2587
 mptcp_worker+0xd13/0x1610 net/mptcp/protocol.c:2739
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706
 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787
 kthread+0x2ef/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

---
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