Subject: [syzbot] [bpf?] [net?] WARNING in sock_map_close (2)

From: syzbot <[email-masked]>
Date: Thu, 22 Aug 2024 06:19:27 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    d785ed945de6 net: wwan: t7xx: PCIe reset rescan
git tree:       net-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15d43b05980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7229118d88b4a71b
dashboard link: https://syzkaller.appspot.com/bug?extid=8dbe3133b840c470da0e
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=13621239980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12378c33980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9b04b4f2471c/disk-d785ed94.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2db64580639d/vmlinux-d785ed94.xz
kernel image: https://storage.googleapis.com/syzbot-assets/04e43f8b9f9b/bzImage-d785ed94.xz

The issue was bisected to:

commit 4a4cd70369f162f819b7855b0eabcb2db21f01f4
Author: James Chapman <[email-masked]>
Date:   Mon Jul 29 15:38:04 2024 +0000

    l2tp: don't set sk_user_data in tunnel socket

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=157a0791980000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=177a0791980000
console output: https://syzkaller.appspot.com/x/log.txt?x=137a0791980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]
Fixes: 4a4cd70369f1 ("l2tp: don't set sk_user_data in tunnel socket")

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5225 at net/core/sock_map.c:1699 sock_map_close+0x399/0x3d0 net/core/sock_map.c:1699
Modules linked in:
CPU: 0 UID: 0 PID: 5225 Comm: syz-executor110 Not tainted 6.11.0-rc3-syzkaller-00508-gd785ed945de6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:sock_map_close+0x399/0x3d0 net/core/sock_map.c:1699
Code: 48 89 df e8 e9 a3 5a f8 4c 8b 23 eb 05 e8 8f 5e f3 f7 e8 ba ea ff ff 4c 89 ef e8 82 e1 da ff e9 47 ff ff ff e8 78 5e f3 f7 90 <0f> 0b 90 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc
RSP: 0018:ffffc900035b7b10 EFLAGS: 00010293
RAX: ffffffff89a02af8 RBX: ffffffff95312d30 RCX: ffff88802424da00
RDX: 0000000000000000 RSI: ffffffff8c0ad560 RDI: ffffffff8c606900
RBP: 0000000000000000 R08: ffffffff937328e7 R09: 1ffffffff26e651c
R10: dffffc0000000000 R11: fffffbfff26e651d R12: ffffffff89a02760
R13: ffff88802fc0a800 R14: dffffc0000000000 R15: ffffffff89a02791
FS:  0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff975386110 CR3: 000000000e734000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 inet_release+0x17d/0x200 net/ipv4/af_inet.c:437
 __sock_release net/socket.c:659 [inline]
 sock_close+0xbc/0x240 net/socket.c:1421
 __fput+0x24a/0x8a0 fs/file_table.c:422
 task_work_run+0x24f/0x310 kernel/task_work.c:228
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2f/0x27f0 kernel/exit.c:882
 do_group_exit+0x207/0x2c0 kernel/exit.c:1031
 __do_sys_exit_group kernel/exit.c:1042 [inline]
 __se_sys_exit_group kernel/exit.c:1040 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff97530ad09
Code: Unable to access opcode bytes at 0x7ff97530acdf.
RSP: 002b:00007ffc8457e748 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff97530ad09
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 00007ff9753852b0 R08: ffffffffffffffb8 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 00007ff9753852b0
R13: 0000000000000000 R14: 00007ff975385d00 R15: 00007ff9752dbf60
 </TASK>

---
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