------------[ cut here ]------------
!valid_signal(sig)
WARNING: kernel/signal.c:2174 at do_notify_parent+0xd18/0xe30 kernel/signal.c:2174, CPU#1: syz.0.31/5966
Modules linked in:
CPU: 1 UID: 0 PID: 5966 Comm: syz.0.31 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:do_notify_parent+0xd18/0xe30 kernel/signal.c:2174
Code: c6 05 20 23 90 0e 01 48 c7 c7 e0 3a cb 8b be a3 08 00 00 48 c7 c2 60 3c cb 8b e8 c3 8c 17 00 e9 2e fa ff ff e8 59 50 3b 00 90 <0f> 0b 90 45 31 e4 e9 1c ff ff ff e8 48 50 3b 00 90 0f 0b 90 e9 db
RSP: 0018:ffffc900033a7c40 EFLAGS: 00010093
RAX: ffffffff818a5bc7 RBX: dffffc0000000000 RCX: ffff888077f91ec0
RDX: 0000000000000000 RSI: 0000000000000091 RDI: 0000000000000040
RBP: ffffc900033a7d90 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000674fa4 R12: ffff888028d74890
R13: ffff888077f91ec0 R14: 0000000000000091 R15: 1ffff92000674f90
FS:  0000000000000000(0000) GS:ffff888125390000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000000 CR3: 0000000032f52000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 exit_notify kernel/exit.c:757 [inline]
 do_exit+0x13f1/0x22c0 kernel/exit.c:987
 __do_sys_exit kernel/exit.c:1084 [inline]
 __se_sys_exit kernel/exit.c:1082 [inline]
 __x64_sys_exit+0x40/0x40 kernel/exit.c:1082
 x64_sys_call+0x2231/0x2240 arch/x86/include/generated/asm/syscalls_64.h:61
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fedb379cdd9
Code: Unable to access opcode bytes at 0x7fedb379cdaf.
RSP: 002b:00007fff5f4639a8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c
RAX: ffffffffffffffda RBX: 00007fedb3a15fa0 RCX: 00007fedb379cdd9
RDX: 000055557a722808 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fedb3832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fedb3a15fac R14: 00007fedb3a15fa0 R15: 00007fedb3a15fa0
 </TASK>