Subject: [syzbot] [perf?] WARNING in __perf_event_overflow (2)

From: syzbot <[email-masked]>
Date: Thu, 08 May 2025 02:57:29 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    f263336a41da selftests/bpf: Add btf dedup test covering mo..
git tree:       bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16d3db68580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a9a25b7a36123454
dashboard link: https://syzkaller.appspot.com/bug?extid=2524754f17993441bf66
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11d3db68580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8b191964c33b/disk-f263336a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fde84e52fec4/vmlinux-f263336a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e2686ad850de/bzImage-f263336a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

------------[ cut here ]------------
WARNING: CPU: 1 PID: 6044 at kernel/events/core.c:10226 __perf_event_overflow+0xaf9/0xe10 kernel/events/core.c:10226
Modules linked in:
CPU: 1 UID: 0 PID: 6044 Comm: syz.1.17 Not tainted 6.15.0-rc4-syzkaller-gf263336a41da #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:__perf_event_overflow+0xaf9/0xe10 kernel/events/core.c:10226
Code: 89 3e 4c 8b 3c 24 e9 c3 fc ff ff e8 21 77 d0 ff 49 bd 00 00 00 00 00 fc ff df 4c 8b 74 24 28 e9 06 fe ff ff e8 08 77 d0 ff 90 <0f> 0b 90 e9 1b ff ff ff e8 fa 76 d0 ff 48 c7 c7 80 b3 73 8b e8 0e
RSP: 0000:ffffc90002f179c0 EFLAGS: 00010293
RAX: ffffffff81ef47c8 RBX: ffff888011140c40 RCX: ffff88802fd43c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002f17ad0 R08: ffff888011140e7f R09: 1ffff110022281cf
R10: dffffc0000000000 R11: ffffed10022281d0 R12: ffffc90002f17f58
R13: dffffc0000000000 R14: ffff888011140e78 R15: 0000000000000000
FS:  00007f2cfb8cd6c0(0000) GS:ffff8881261cc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2cfb8cd0e8 CR3: 0000000032960000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 perf_swevent_overflow kernel/events/core.c:10324 [inline]
 perf_swevent_event+0x2f4/0x5e0 kernel/events/core.c:-1
 do_perf_sw_event kernel/events/core.c:10464 [inline]
 ___perf_sw_event+0x4a1/0x700 kernel/events/core.c:10491
 __perf_sw_event+0xfa/0x1a0 kernel/events/core.c:10503
 perf_sw_event include/linux/perf_event.h:1537 [inline]
 do_user_addr_fault+0x12e4/0x1390 arch/x86/mm/fault.c:1284
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x68/0x110 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f2cfa85eb1b
Code: 00 74 24 80 3d d8 6b e8 00 00 0f b6 35 ce 6b e8 00 75 4c 80 3d c9 6b e8 00 00 75 43 40 84 f6 75 3e 66 0f 1f 44 00 00 48 89 ef <e8> 60 fa ff ff 8b 45 0c 85 c0 75 38 b9 40 42 0f 00 ba 81 00 00 00
RSP: 002b:00007f2cfb8cd0f0 EFLAGS: 00010246
RAX: 0000000000000001 RBX: 00007f2cfabb5fa8 RCX: 00007f2cfa98e969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2cfabb5fa0
RBP: 00007f2cfabb5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2cfabb5fac
R13: 0000000000000000 R14: 00007ffe3a7ce340 R15: 00007ffe3a7ce428
 </TASK>

---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email-masked].

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup