From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f207.google.com (mail-oi1-f207.google.com [209.85.167.207]) (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 478C8390CAB for ; Wed, 24 Jun 2026 07:20:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782285634; cv=none; b=h7T/iTQHkXFJqj7AdBrQTz2XwK5xlxLcqGzHhiIW07l22NI51MGSNIaBFoJft5UwjnjT0RTnOe5qZOUVGwh1WtILkLbgDlt9qAgIKtZ8GaRlPHZFLrCPKKfLHMxQs540/iACL0YQ/ORlhEqQr7Zf/UxEgrayX0+d8t4fJBOWyfE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782285634; c=relaxed/simple; bh=/mXRt1KgB2yMYu4eVE5/zbBtVw4HiXvrXoJ6kF5tXWo=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=GbRCSnL3z6sMgKbtvp+wMcWl37xb5CT8+dSnebA9zj/ZyeNQHcBinbHk73dLSplToq1Vvaz+B8D5s0oLTQSks6PwQp/ipgpzPPgBPdCO8tClgTA6uBmp/i6qjwq9dkAEKvRVQpCfAGpzcdcdqyqQjeTW2RRgoWltOMOGylLApU8= 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=209.85.167.207 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-oi1-f207.google.com with SMTP id 5614622812f47-486a2231742so1057451b6e.1 for ; Wed, 24 Jun 2026 00:20:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782285628; x=1782890428; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=efjZMiDv/qOd8uxrTrxuiqmStDg8HEmf+X6Ut6FB9Io=; b=iMclIFo5qS+LTlwYLGpglyOererTgAWqoDI2tnVQG03wcm83nYN60Wk5XRmyaG6Ukx rrB+WBz+H1RKFH670MChbOc7e43IrHxdKEU82w9AS5m0gIxF8J/mMWnfrA+SyoeED39r gi31jDGPDI/atrr6gpUhR5GwwEW390vrtMP7xS5dUuVHR6z9c/EzelhOWzXDsjWCA9gX DJfVwWUBYC5SAVbtunqAiL3Hmc3aGU3aS/ObDQArXF4AQEwBlwMZTL/P1lNA52dwhK8x bUMOcJQfzaCz+l+wWXzud7inFrSJmCxOU5SrmHRPvU2MPVDDXWQjh+yhFxVvBlj31OGQ w9kg== X-Forwarded-Encrypted: i=1; AFNElJ+QZeSj4Zs7xl94rH9R5iX7d2mNwkHYXfoqdNH9mSkSpqocSs18EC4fdlMe3T6toq/idZw4RQE=@vger.kernel.org X-Gm-Message-State: AOJu0YxwlPPMTsszn39KlrQVpRwnPF32LzFUn/YwV5WjD4jdIZYfKr7p eqmdnh8FMOfNKizT2gHnJzJTGG2DZSA+7hRTQXFkImrRh3cUlDh8Ne1A5IuVea4e5Mf8EOu/5AI WMy2zrh311LF2fILzv9ouoFDceXe7uj7HrjxyEoM/un5BWEiONh6yN1LDXNM= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:3a0e:b0:48a:b0cb:6589 with SMTP id 5614622812f47-48ee2f56a73mr4407274b6e.13.1782285627826; Wed, 24 Jun 2026 00:20:27 -0700 (PDT) Date: Wed, 24 Jun 2026 00:20:27 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a3b853b.52ae72c2.136ac7.000c.GAE@google.com> Subject: [syzbot] [net?] WARNING in qdisc_pkt_len_segs_init From: syzbot To: davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 9c87e61e3c57 Merge tag 'bpf-next-7.2' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10d2901c580000 kernel config: https://syzkaller.appspot.com/x/.config?x=9a9f723a32776544 dashboard link: https://syzkaller.appspot.com/bug?extid=d5d0d598a4cfdfafdc3b compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/5489ff1c0660/disk-9c87e61e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/bcdabd5a8fea/vmlinux-9c87e61e.xz kernel image: https://storage.googleapis.com/syzbot-assets/fa77e3b769c6/bzImage-9c87e61e.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d5d0d598a4cfdfafdc3b@syzkaller.appspotmail.com ------------[ cut here ]------------ len > ((int)(~0U >> 1)) WARNING: ./include/linux/skbuff.h:2866 at pskb_may_pull_reason include/linux/skbuff.h:2866 [inline], CPU#0: syz.0.5520/24128 WARNING: ./include/linux/skbuff.h:2866 at pskb_may_pull include/linux/skbuff.h:2884 [inline], CPU#0: syz.0.5520/24128 WARNING: ./include/linux/skbuff.h:2866 at qdisc_pkt_len_segs_init+0x4b4/0xa30 net/core/dev.c:4138, CPU#0: syz.0.5520/24128 Modules linked in: CPU: 0 UID: 0 PID: 24128 Comm: syz.0.5520 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:pskb_may_pull_reason include/linux/skbuff.h:2866 [inline] RIP: 0010:pskb_may_pull include/linux/skbuff.h:2884 [inline] RIP: 0010:qdisc_pkt_len_segs_init+0x4b4/0xa30 net/core/dev.c:4138 Code: 00 00 02 00 31 ff e8 1b 3d 49 f8 81 e3 00 00 02 00 0f 85 fd 00 00 00 e8 ca 38 49 f8 45 89 e7 e9 2c ff ff ff e8 bd 38 49 f8 90 <0f> 0b 90 e9 ee fd ff ff 44 89 e7 89 de e8 6a 3a 49 f8 41 39 dc 0f RSP: 0018:ffffc90000007660 EFLAGS: 00010246 RAX: ffffffff897ccc53 RBX: 0000000000000003 RCX: ffff8880761b8000 RDX: 0000000000000100 RSI: 00000000fffffffa RDI: 0000000000000000 RBP: ffff888034a70b40 R08: ffff88807bd48067 R09: 1ffff1100f7a900c R10: dffffc0000000000 R11: ffffed100f7a900d R12: 00000000fffffffa R13: dffffc0000000000 R14: 1ffff1100694e183 R15: ffff888068a29b98 FS: 00007f26d46806c0(0000) GS:ffff888125272000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000010000 CR3: 00000000894be000 CR4: 00000000003526f0 DR0: 0000000000000006 DR1: 0000000000000000 DR2: 000000007fffdff5 DR3: 0000800000000005 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: sch_handle_ingress net/core/dev.c:4479 [inline] __netif_receive_skb_core+0x13aa/0x30b0 net/core/dev.c:6057 __netif_receive_skb_list_core+0x24d/0x830 net/core/dev.c:6281 __netif_receive_skb_list net/core/dev.c:6348 [inline] netif_receive_skb_list_internal+0x995/0xcf0 net/core/dev.c:6439 gro_normal_list include/net/gro.h:523 [inline] gro_flush_normal include/net/gro.h:531 [inline] napi_complete_done+0x299/0x730 net/core/dev.c:6807 gro_cell_poll+0x5ab/0x5d0 net/core/gro_cells.c:74 __napi_poll+0xaa/0x330 net/core/dev.c:7729 napi_poll net/core/dev.c:7792 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7949 handle_softirqs+0x225/0x840 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] tun_rx_batched+0x616/0x790 drivers/net/tun.c:-1 tun_get_user+0x2b04/0x4350 drivers/net/tun.c:1986 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:2032 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f26d379ce59 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:00007f26d4680028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f26d3a15fa0 RCX: 00007f26d379ce59 RDX: 000000000000fdef RSI: 00002000000002c0 RDI: 000000000000000a RBP: 00007f26d3832d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f26d3a16038 R14: 00007f26d3a15fa0 R15: 00007f26d3b3fa48 --- 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