------------[ cut here ]------------
!valid_signal(sig)
WARNING: kernel/signal.c:2174 at do_notify_parent+0xd18/0xe30 kernel/signal.c:2174, CPU#1: syz.8.5137/22752
Modules linked in:
CPU: 1 UID: 0 PID: 22752 Comm: syz.8.5137 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:do_notify_parent+0xd18/0xe30 kernel/signal.c:2174
Code: c6 05 0a 06 93 0e 01 48 c7 c7 20 36 cb 8b be a3 08 00 00 48 c7 c2 a0 37 cb 8b e8 c3 8c 17 00 e9 2e fa ff ff e8 79 3e 3b 00 90 <0f> 0b 90 45 31 e4 e9 1c ff ff ff e8 68 3e 3b 00 90 0f 0b 90 e9 db
RSP: 0018:ffffc900055f7c40 EFLAGS: 00010093
RAX: ffffffff8189d697 RBX: dffffc0000000000 RCX: ffff888027983d80
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 0000000000000040
RBP: ffffc900055f7d90 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000abefa4 R12: ffff888029566590
R13: ffff888027983d80 R14: 0000000000000080 R15: 1ffff92000abef90
FS:  0000000000000000(0000) GS:ffff88812532b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5aaac527f0 CR3: 000000000e74a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000008d24 DR6: 00000000ffff0ff0 DR7: 0000000000000600
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: 0033:0x7f5aaad9c819
Code: Unable to access opcode bytes at 0x7f5aaad9c7ef.
RSP: 002b:0000200000002198 EFLAGS: 00000246 ORIG_RAX: 000000000000003c
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007f5aaad9c819
RDX: 00007f5aaad9c819 RSI: 00002000000021c0 RDI: 000000000000000b
RBP: 00007f5aaae32c91 R08: 00002000000027c0 R09: 029606d2297a285f
R10: 00002000000027c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5aab016128 R14: 00007f5aab016090 R15: 00007ffd127a3d78
 </TASK>