From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f80.google.com (mail-oo1-f80.google.com [209.85.161.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CED2337756C for ; Mon, 20 Apr 2026 14:13:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776694412; cv=none; b=adktj+8YU3rTuoH4rZFzk4yDQ2h2YUJuOOLD2Qs6NzicS66LDEX6cKbp3TLzRtxBT/HhaWl3If1WGw0KFLQw5OGfS1xdF0vXf2qxxsLyVsSZAY3oHB82ZBCpePQ6JwfPgZ6LAnSLn5vlHkT3Oz4UK8fcw+9JirBMtXI4KRtzm6w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776694412; c=relaxed/simple; bh=4P7tjYeFwzDriQN7839r2lcY7V+saoSEVnCBR8gEMj0=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=WALTjRte2Jn1gIqH79ysTfVjMZAAgI5223KcAjQXFWjwybNEmGqhhJaUFWsKE/RO8BtRKVGqO0GUp2NRhF2r5TM8jz5wqUmHC+VkIUooElBYLvR52m8mhb3iJdP0rNAU/rO6RJJvdPyqvK04I9HesqfLB6ItNF5265cSd0fIjHg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.161.80 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo1-f80.google.com with SMTP id 006d021491bc7-68bf09fdb30so2378332eaf.3 for ; Mon, 20 Apr 2026 07:13:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776694410; x=1777299210; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=Pz5IG1ReLdvDb8TqqFXwRlQy6RDGxX98ZSQADPiXJ2I=; b=P23qoPUVk+xHGUFYGrcctFPOiWInWkcIRm8MG7RGpvoxiUtcQntTzOdnHDsccZ4UCu KLBVGZnOOXcp/hl+yK3RZc2/6ICQdyqgBw51SN26DTAeOJT+KcAFaqicvBfR8WhYUqq5 V/P57nAOsaIaOLhmaNlZxPeT1N8o2FIC4jaJKJX7zrjcUbt/NAejOVSKEsqX3M36TqDj U38eD5FmOolgXbSYiwB8QHkTXDXXTAidIm6pCcglwu7dVzRYKPqunjhVFEhHLFVvJkkM ElbTPlAaOmeRQDitGTbtijAzMI6nAPWB9+uxaA5eYRl6woYSM20ODXEQjWNj8kBkfS7j JOqw== X-Forwarded-Encrypted: i=1; AFNElJ82sWGxgUV1ZrkQaN2OXAQE+TVYpzQQaBJ0rj+/e01I4vWb1mq9MdeUIHYlyag4DPcFYS3uX+dDHlaYz4s=@vger.kernel.org X-Gm-Message-State: AOJu0Yxib4WOH3HIL+DGE7BXieM496q6VjMlq+ODBwwtQqz85gDgqVoB NVlipe//xL7L2oHNLR5NgoiyjGQ88NstgWfwCE6bm/IBMBXcR1bMcSRoCOYCgpnNbJf0u+HEzxJ pMvD0V3Tx78OEfetxMf9gKzphIn/gwoZcE/V+JzXoDxQyX93QM5aOfXbPZ0g= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:2083:b0:67b:bd89:90ed with SMTP id 006d021491bc7-69462f0f2c2mr7857438eaf.41.1776694409738; Mon, 20 Apr 2026 07:13:29 -0700 (PDT) Date: Mon, 20 Apr 2026 07:13:29 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69e63489.a00a0220.17a17.0005.GAE@google.com> Subject: [syzbot] [bpf?] KCSAN: data-race in bpf_obj_memcpy / bpf_obj_memcpy From: syzbot To: andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org, daniel@iogearbox.net, eddyz87@gmail.com, jolsa@kernel.org, linux-kernel@vger.kernel.org, martin.lau@linux.dev, memxor@gmail.com, song@kernel.org, syzkaller-bugs@googlegroups.com, yonghong.song@linux.dev Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: c1f49dea2b8f Merge tag 'mm-hotfixes-stable-2026-04-19-00-1.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10ec34ce580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d3740f7f69b18f59 dashboard link: https://syzkaller.appspot.com/bug?extid=44044637ef892e79ca2b compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/4ed91de40e47/disk-c1f49dea.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/7353bf53627b/vmlinux-c1f49dea.xz kernel image: https://storage.googleapis.com/syzbot-assets/ab6db1fcd59d/bzImage-c1f49dea.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+44044637ef892e79ca2b@syzkaller.appspotmail.com netlink: 676 bytes leftover after parsing attributes in process `syz.4.735'. ================================================================== BUG: KCSAN: data-race in bpf_obj_memcpy / bpf_obj_memcpy write to 0xffffe8ffffa24c00 of 1404 bytes by task 6603 on cpu 0: bpf_obj_memcpy+0x13c/0x1a0 include/linux/bpf.h:-1 copy_map_value include/linux/bpf.h:557 [inline] bpf_percpu_array_update+0x1e1/0x2d0 kernel/bpf/arraymap.c:443 bpf_map_update_value+0x260/0x570 kernel/bpf/syscall.c:275 generic_map_update_batch+0x52d/0x680 kernel/bpf/syscall.c:2025 bpf_map_do_batch+0x25c/0x380 kernel/bpf/syscall.c:5689 __sys_bpf+0x6a2/0x7e0 kernel/bpf/syscall.c:-1 __do_sys_bpf kernel/bpf/syscall.c:6361 [inline] __se_sys_bpf kernel/bpf/syscall.c:6359 [inline] __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:6359 x64_sys_call+0x10cb/0x3020 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f write to 0xffffe8ffffa24c00 of 1404 bytes by task 6604 on cpu 1: bpf_obj_memcpy+0x13c/0x1a0 include/linux/bpf.h:-1 copy_map_value include/linux/bpf.h:557 [inline] bpf_percpu_array_update+0x1e1/0x2d0 kernel/bpf/arraymap.c:443 bpf_map_update_value+0x260/0x570 kernel/bpf/syscall.c:275 generic_map_update_batch+0x52d/0x680 kernel/bpf/syscall.c:2025 bpf_map_do_batch+0x25c/0x380 kernel/bpf/syscall.c:5689 __sys_bpf+0x6a2/0x7e0 kernel/bpf/syscall.c:-1 __do_sys_bpf kernel/bpf/syscall.c:6361 [inline] __se_sys_bpf kernel/bpf/syscall.c:6359 [inline] __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:6359 x64_sys_call+0x10cb/0x3020 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 6604 Comm: syz.4.735 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 ================================================================== --- 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 syzkaller@googlegroups.com. 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 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