Re: [syzbot] [perf?] WARNING in perf_event_open

syzbot
2023-12-25T11:44:23Z

syzbot has found a reproducer for the following issue on:

HEAD commit: 5abde6246522 bpf: Avoid unnecessary use of comma operator ..
git tree: bpf-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=122f1609e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=8f565e10f0b1e1fc
dashboard link: https://syzkaller.appspot.com/bug?extid=07144c543a5c002c7305
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14857e81e80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1126ac36e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a270020a37dc/disk-5abde624.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6b0eb142c0ea/vmlinux-5abde624.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d6ceb3e9bf6a/bzImage-5abde624.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+07144c543a5c002c7305@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 5061 at kernel/events/core.c:1950 perf_event_validate_size kernel/events/core.c:1950 [inline]
WARNING: CPU: 0 PID: 5061 at kernel/events/core.c:1950 __do_sys_perf_event_open+0x2748/0x2c70 kernel/events/core.c:12655
Modules linked in:
CPU: 0 PID: 5061 Comm: syz-executor128 Not tainted 6.7.0-rc5-syzkaller-01540-g5abde6246522 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:perf_event_validate_size kernel/events/core.c:1950 [inline]
RIP: 0010:__do_sys_perf_event_open+0x2748/0x2c70 kernel/events/core.c:12655
Code: ff 48 8d b8 a8 00 00 00 e8 55 07 cf 08 bf 01 00 00 00 89 c3 89 c6 e8 47 71 d5 ff 83 eb 01 0f 84 2d ed ff ff e8 c9 75 d5 ff 90 <0f> 0b 90 e9 1f ed ff ff e8 bb 75 d5 ff be 03 00 00 00 48 89 ef e8
RSP: 0018:ffffc9000398fd90 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: ffffffff81b227c9
RDX: ffff8880794c3b80 RSI: ffffffff81b227d7 RDI: 0000000000000005
RBP: ffff888017e68608 R08: 0000000000000005 R09: 0000000000000001
R10: 0000000000000000 R11: ffffffff915ec900 R12: ffff888024db5800
R13: 1ffff92000731fbd R14: ffff8880794c3b80 R15: ffff888017e68608
FS: 0000555555ca6380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000006c CR3: 0000000059a59000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fddcf7ef369
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc7c42b4a8 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007ffc7c42b688 RCX: 00007fddcf7ef369
RDX: 00000000ffffffff RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fddcf862610 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc7c42b678 R14: 0000000000000001 R15: 0000000000000001
</TASK>

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