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 D4A5C3F1ABE for ; Tue, 19 May 2026 11:56:32 +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=1779191794; cv=none; b=LoW94enexwZikatvpCmOuzCtngp+dSzAZm9aRTgk/XjNzaWtkunBUa4f4QmaMva6zncH3oZ+Eq5WL6X5HEzmqF/8c8B58EiM1DsyhzX3Q8HtMll1WJB5rPiAzXXummuKHIDYomvm5OE+fV0i5Ee7tCjlhanBNfCrOR/fMmasxpw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779191794; c=relaxed/simple; bh=6EHyX+t59JQk8qaGatmxGZ3pdkNuXcSnsYDgZnyNEp4=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=eYkP0mvf9xYFhAdU3moSRzh4u/okJDnlxvoQUHOZEdPGinLmmJ9qgI1Jicj6hVQQDuFw738FosG8hWDiNpc9aoDIiulu1EZYidX+Q7j0Bp87stA6zskBrD59XISVRyC0zM6hIBlQY5zNvGLmmg/yLIp01nds3O4+IiX8f7zeaS0= 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 006d021491bc7-68e924f632bso6754411eaf.0 for ; Tue, 19 May 2026 04:56:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779191792; x=1779796592; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=P1p6VfNC57KjkmyCN/S20TDWRsKpJFRMJHYp7VVD08s=; b=CQ8li9+E8SATKHZ5NAfjL8q1z0iz77u1VD3D5HIII+ms33CYRcGLmwLDB+vKiRNHk9 pEO1vrT2Wp8nFtxYwbxC98EG+U0ktHFBaPeyRGRlFAUaWx784ZYj2bAqi9eEH8ssrMdg ft/pji7rRSSJkzIyJdRk928p4QOQHr5GfH2U3qp2MbmV9XL6BdyiC0dgp9musQHkNJP4 FiNgS75oek6ByEAC/be1DTxsxPZUorUSXYFa41MbmxTc6dVQ0maRDJaRMJ7IecLOCxA9 voPAhUeYA9JFQQbOhwXtDmv6d9NSukffl3Z8/2PX2KoASScTRvDifG7TdZiaVor0i6pQ zpCg== X-Forwarded-Encrypted: i=1; AFNElJ9few5RKxzEQ/YNXUyVtNbgStZvRoPEGupmBYpwz/7txfMISnz1Td2jmOeQlO1Xjx/d42YS/g4=@vger.kernel.org X-Gm-Message-State: AOJu0Yxaqo6Gw7FxSJSsJFqhvPvy1Cz7usrShkrzDSld3H8ojMlnO9T1 1sA8GufrA1XHRJBVUmPp4d9CMZFIywXE8nhRnYUc4C8RGHdpNW80pJvGE6xBYZ2gjMEEAXgONqO Ds5BeigQ8NDMgncIMxLM6A/H8e/nVh4wyzOFF6ePbSrhHAuZSoA04y+EFNho= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a4a:e916:0:b0:68a:116a:a5e5 with SMTP id 006d021491bc7-69c9bfb0957mr12376940eaf.44.1779191791837; Tue, 19 May 2026 04:56:31 -0700 (PDT) Date: Tue, 19 May 2026 04:56:31 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a0c4fef.170a0220.25463a.022e.GAE@google.com> Subject: [syzbot] [netfilter?] BUG: using smp_processor_id() in preemptible code in cpu_mt From: syzbot To: coreteam@netfilter.org, davem@davemloft.net, edumazet@google.com, fw@strlen.de, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pabeni@redhat.com, pablo@netfilter.org, phil@nwl.cc, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 50d00ea66086 Merge branch 'bpf-follow-up-fixes-for-stack-a.. git tree: bpf-next console output: https://syzkaller.appspot.com/x/log.txt?x=17f258c8580000 kernel config: https://syzkaller.appspot.com/x/.config?x=4caf64b1ee83dac0 dashboard link: https://syzkaller.appspot.com/bug?extid=690d3e3ffa7335ac10eb 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/dbc6ccaf15bc/disk-50d00ea6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9160c9066e5c/vmlinux-50d00ea6.xz kernel image: https://storage.googleapis.com/syzbot-assets/b6f1c3abffde/bzImage-50d00ea6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+690d3e3ffa7335ac10eb@syzkaller.appspotmail.com BUG: using smp_processor_id() in preemptible [00000000] code: syz.3.1377/11941 caller is cpu_mt+0x53/0xd0 net/netfilter/xt_cpu.c:37 CPU: 1 UID: 0 PID: 11941 Comm: syz.3.1377 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 check_preemption_disabled+0xd3/0xe0 lib/smp_processor_id.c:47 cpu_mt+0x53/0xd0 net/netfilter/xt_cpu.c:37 __nft_match_eval net/netfilter/nft_compat.c:412 [inline] nft_match_eval+0x1ad/0x2b0 net/netfilter/nft_compat.c:442 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x48d/0x1ae0 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook+0x22a/0x3a0 include/linux/netfilter.h:273 NF_HOOK_COND include/linux/netfilter.h:306 [inline] ip_output+0x269/0x450 net/ipv4/ip_output.c:438 __ip_queue_xmit+0x116a/0x1bb0 net/ipv4/ip_output.c:534 sctp_packet_transmit+0x246f/0x2ac0 net/sctp/output.c:653 sctp_packet_singleton+0x234/0x340 net/sctp/outqueue.c:783 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline] sctp_outq_flush+0x50d/0x31b0 net/sctp/outqueue.c:1212 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:-1 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline] sctp_do_sm+0x54c7/0x5cf0 net/sctp/sm_sideeffect.c:1175 sctp_primitive_ASSOCIATE+0x95/0xc0 net/sctp/primitive.c:73 sctp_sendmsg_to_asoc+0x143d/0x1900 net/sctp/socket.c:1840 sctp_sendmsg+0x1b3d/0x2c10 net/sctp/socket.c:2030 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x80a/0x9f0 net/socket.c:2698 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752 __sys_sendmsg net/socket.c:2784 [inline] __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787 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: 0033:0x7ff6e519ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff6e33f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ff6e5415fa0 RCX: 00007ff6e519ce59 RDX: 00000000000480d1 RSI: 0000200000000140 RDI: 0000000000000003 RBP: 00007ff6e5232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff6e5416038 R14: 00007ff6e5415fa0 R15: 00007ffdfe9dd548 --- 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