[Android 5.15] kernel BUG in pskb_expand_head

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a71626bd56a5 Merge 5.15.189 into android13-5.15-lts
git tree: android13-5.15-lts
console+strace: https://syzkaller.appspot.com/x/log.txt?x=14961b82580000
kernel config: https://syzkaller.appspot.com/x/.config?x=99aab5d4da474d05
dashboard link: https://syzkaller.appspot.com/bug?extid=30e65637741adeefd34e
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12961b82580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11e980a2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c25f40277cd0/disk-a71626bd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3e31c472cf40/vmlinux-a71626bd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a11f9fac7b36/bzImage-a71626bd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+30e656...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:1727!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 39 Comm: kworker/1:1 Not tainted 5.15.189-syzkaller-00079-ga71626bd56a5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events sk_psock_backlog
RIP: 0010:pskb_expand_head+0x11a5/0x11d0 net/core/skbuff.c:1727
Code: 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c de f3 ff ff 4c 89 e7 e8 8c 9a f6 fd e9 d1 f3 ff ff e8 42 22 b8 fd 0f 0b e8 3b 22 b8 fd <0f> 0b 48 8b 4d d0 80 e1 07 80 c1 03 38 c1 0f 8c b2 fa ff ff 48 8b
RSP: 0018:ffffc9000028fa08 EFLAGS: 00010293
RAX: ffffffff83b08d95 RBX: dffffc0000000000 RCX: ffff8881087862c0
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffffc9000028faa8 R08: dffffc0000000000 R09: ffffed1024290a6e
R10: ffffed1024290a6e R11: 1ffff11024290a6d R12: 0000000000000e80
R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000008080
FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009000 CR3: 000000010d8d9000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__pskb_pull_tail+0xb1/0x1480 net/core/skbuff.c:2281
__skb_linearize include/linux/skbuff.h:3529 [inline]
skb_linearize include/linux/skbuff.h:3541 [inline]
sk_psock_skb_ingress_enqueue+0x67/0x410 net/core/skmsg.c:539
sk_psock_skb_ingress net/core/skmsg.c:583 [inline]
sk_psock_handle_skb net/core/skmsg.c:621 [inline]
sk_psock_backlog+0xa72/0x1230 net/core/skmsg.c:686
process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
kthread+0x411/0x500 kernel/kthread.c:337
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Modules linked in:
---[ end trace d7ef24e870b91c11 ]---
RIP: 0010:pskb_expand_head+0x11a5/0x11d0 net/core/skbuff.c:1727
Code: 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c de f3 ff ff 4c 89 e7 e8 8c 9a f6 fd e9 d1 f3 ff ff e8 42 22 b8 fd 0f 0b e8 3b 22 b8 fd <0f> 0b 48 8b 4d d0 80 e1 07 80 c1 03 38 c1 0f 8c b2 fa ff ff 48 8b
RSP: 0018:ffffc9000028fa08 EFLAGS: 00010293
RAX: ffffffff83b08d95 RBX: dffffc0000000000 RCX: ffff8881087862c0
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: ffffc9000028faa8 R08: dffffc0000000000 R09: ffffed1024290a6e
R10: ffffed1024290a6e R11: 1ffff11024290a6d R12: 0000000000000e80
R13: 0000000000000000 R14: 0000000000000002 R15: 0000000000008080
FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009000 CR3: 000000000660f000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.