[Android 6.1] BUG: unable to handle kernel NULL pointer dereference in sk_psock_verdict_data_ready

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 8481b97df54a BACKPORT: erofs: fix infinite loop due to a r..
git tree: android14-6.1
console output: https://syzkaller.appspot.com/x/log.txt?x=109ba042180000
kernel config: https://syzkaller.appspot.com/x/.config?x=54c503ca94c7e582
dashboard link: https://syzkaller.appspot.com/bug?extid=cff23e68b26608c779a9
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=1705f042180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1380fcec180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fe2cdba69a33/disk-8481b97d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/96ee1ff8a428/vmlinux-8481b97d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c8af4d97f7c0/bzImage-8481b97d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cff23e...@syzkaller.appspotmail.com

BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1209af067 P4D 1209af067 PUD 1209c6067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 440 Comm: syz-executor288 Not tainted 6.1.68-syzkaller-00011-g8481b97df54a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc90001117908 EFLAGS: 00010246
RAX: 1ffff110238c5a97 RBX: ffff88811c62d4b8 RCX: ffff88811ff8a880
RDX: 0000000000000000 RSI: ffff88811c62d400 RDI: ffff88811c474000
RBP: ffffc90001117930 R08: ffffffff841c1357 R09: ffff888100b99980
R10: 0000000000000010 R11: dffffc0000000001 R12: 0000000000000004
R13: dffffc0000000000 R14: ffff88811c474000 R15: dffffc0000000000
FS: 00007f2673a496c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001209c9000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
sk_psock_verdict_data_ready+0x129/0x160 net/core/skmsg.c:1219
unix_stream_sendmsg+0x8fd/0x1070 net/unix/af_unix.c:2245
sock_sendmsg_nosec net/socket.c:716 [inline]
__sock_sendmsg net/socket.c:728 [inline]
____sys_sendmsg+0x5dc/0x9d0 net/socket.c:2499
___sys_sendmsg net/socket.c:2553 [inline]
__sys_sendmsg+0x2a9/0x390 net/socket.c:2582
__do_sys_sendmsg net/socket.c:2591 [inline]
__se_sys_sendmsg net/socket.c:2589 [inline]
__x64_sys_sendmsg+0x7f/0x90 net/socket.c:2589
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f2673aca729
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2673a49218 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2673b54368 RCX: 00007f2673aca729
RDX: 0000000000040000 RSI: 0000000020000980 RDI: 0000000000000003
RBP: 00007f2673b54360 R08: 00007ffc219bb827 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2673b5436c
R13: 00007f2673b21074 R14: 656c6c616b7a7973 R15: 00007ffc219bb828
</TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc90001117908 EFLAGS: 00010246
RAX: 1ffff110238c5a97 RBX: ffff88811c62d4b8 RCX: ffff88811ff8a880
RDX: 0000000000000000 RSI: ffff88811c62d400 RDI: ffff88811c474000
RBP: ffffc90001117930 R08: ffffffff841c1357 R09: ffff888100b99980
R10: 0000000000000010 R11: dffffc0000000001 R12: 0000000000000004
R13: dffffc0000000000 R14: ffff88811c474000 R15: dffffc0000000000
FS: 00007f2673a496c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001209c9000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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