syzbot

Zero length message leads to an empty skb
Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4963 Comm: syz.7.134 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 42400405 (nZcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=jc)
pc : clear_rseq_cs+0xf8/0x140 kernel/rseq.c:-1
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : clear_rseq_cs+0xd8/0x140 kernel/rseq.c:242
sp : ffff80001fee7cd0
x29: ffff80001fee7cd0 x28: ffff0000d7570000 x27: 0000002000000800
x26: 1fffe0001aeae28d x25: dfff800000000000 x24: 0000000000000000
x23: 0000000000400140 x22: dfff800000000000 x21: 0000002000000800
x20: 0000000020000008 x19: 0000000000000001 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800008659ec8 x15: 0000000000000000
x14: 0000000000000000 x13: 1ffff0000282e06b x12: 0000000000080000
x11: 0000000020000008 x10: 0000ffffffffffff x9 : 0000000020000008
x8 : 0000000000000000 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 00000000fffffff2
Call trace:
 clear_rseq_cs+0xf8/0x140 kernel/rseq.c:242
 __do_sys_rseq kernel/rseq.c:410 [inline]
 __se_sys_rseq kernel/rseq.c:350 [inline]
 __arm64_sys_rseq+0x444/0x75c kernel/rseq.c:350
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: 9a9f028b d503229f aa1f03e8 f8000968 (14000003) 
---[ end trace ce50a00392dfb2e4 ]---
----------------
Code disassembly (best guess):
   0:	9a9f028b 	csel	x11, x20, xzr, eq	// eq = none
   4:	d503229f 	csdb
   8:	aa1f03e8 	mov	x8, xzr
   c:	f8000968 	sttr	x8, [x11]
* 10:	14000003 	b	0x1c <-- trapping instruction