linux-kernel - [syzbot] [bpf?] WARNING in maybe_exit

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Message-ID: <68c85acd.050a0220.2ff435.03a4.GAE@google.com>
Date: Mon, 15 Sep 2025 11:28:29 -0700
From: syzbot <syzbot+3afc814e8df1af64b653@...kaller.appspotmail.com>
To: andrii@...nel.org, ast@...nel.org, bpf@...r.kernel.org, 
	daniel@...earbox.net, eddyz87@...il.com, haoluo@...gle.com, 
	john.fastabend@...il.com, jolsa@...nel.org, kpsingh@...nel.org, 
	linux-kernel@...r.kernel.org, martin.lau@...ux.dev, sdf@...ichev.me, 
	song@...nel.org, syzkaller-bugs@...glegroups.com, yonghong.song@...ux.dev
Subject: [syzbot] [bpf?] WARNING in maybe_exit_scc

Hello,

syzbot found the following issue on:

HEAD commit:    f83ec76bf285 Linux 6.17-rc6
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=137d0e42580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8f01d8629880e620
dashboard link: https://syzkaller.appspot.com/bug?extid=3afc814e8df1af64b653
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=104a947c580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14467b62580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/be9b26c66bc1/disk-f83ec76b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/53dc5627e608/vmlinux-f83ec76b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/398506a67fd8/bzImage-f83ec76b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3afc814e8df1af64b653@...kaller.appspotmail.com

------------[ cut here ]------------
verifier bug: scc exit: no visit info for call chain (1)(1)
WARNING: CPU: 1 PID: 6013 at kernel/bpf/verifier.c:1949 maybe_exit_scc+0x768/0x8d0 kernel/bpf/verifier.c:1949
Modules linked in:
CPU: 1 UID: 0 PID: 6013 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:maybe_exit_scc+0x768/0x8d0 kernel/bpf/verifier.c:1949
Code: ff ff e8 cb 8e e7 ff c6 05 0a b5 bf 0e 01 90 48 89 ee 48 89 df e8 f8 41 fb ff 48 c7 c7 a0 9b b5 8b 48 89 c6 e8 59 33 a6 ff 90 <0f> 0b 90 90 e9 4e ff ff ff e8 0a ee 4d 00 e9 7f f9 ff ff 4c 8b 4c
RSP: 0018:ffffc900041bf500 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff888079840000 RCX: ffffffff817a4388
RDX: ffff88807d3f8000 RSI: ffffffff817a4395 RDI: 0000000000000001
RBP: ffff888079846328 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 1ffff92000837ea7
R13: 0000000000000000 R14: ffff88805cf87400 R15: dffffc0000000000
FS:  000055557c9b5500(0000) GS:ffff8881247b2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557c9b5808 CR3: 0000000073b4d000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 update_branch_counts kernel/bpf/verifier.c:2040 [inline]
 do_check kernel/bpf/verifier.c:20135 [inline]
 do_check_common+0x20cc/0xb410 kernel/bpf/verifier.c:23264
 do_check_main kernel/bpf/verifier.c:23347 [inline]
 bpf_check+0x869f/0xc670 kernel/bpf/verifier.c:24707
 bpf_prog_load+0xe41/0x2490 kernel/bpf/syscall.c:2979
 __sys_bpf+0x4a3f/0x4de0 kernel/bpf/syscall.c:6029
 __do_sys_bpf kernel/bpf/syscall.c:6139 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6137 [inline]
 __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:6137
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd1d078eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffee0400aa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fd1d09d5fa0 RCX: 00007fd1d078eba9
RDX: 0000000000000048 RSI: 00002000000017c0 RDI: 0000000000000005
RBP: 00007fd1d0811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd1d09d5fa0 R14: 00007fd1d09d5fa0 R15: 0000000000000003
 </TASK>


---
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