From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f77.google.com (mail-io1-f77.google.com [209.85.166.77]) (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 8CBC93A29F for ; Sat, 25 May 2024 17:37:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716658651; cv=none; b=QnlCmMWZ9qE+vQRxfPGblloGBre5/Fb3Wf0Ynvlx7SFPht1YniaItV4U1h+PNqLBjkSqFtKFutrC06j2VXoj2LvoHgbDTgloJeBcrYU0l2ZAxloL6BTVEWR8v1og5Xkl4/vsrhHmI7TIWH7pjR3yTYa3pmeG1Dqi1Goe8Oyiwf8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716658651; c=relaxed/simple; bh=dymEk7UzsFzhEBsmvHw0fIyLacTUFRLb/BoWOZz72b4=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=VAol2ZzRLfVhUp8Nx+km2E8xukAjsVFKeBQxo0zVWVhn2HXuAFuynu5ddExDhhpnkFehBwToK6+BxdlrfG5k1aFTHA+9V56vzt/Wrct92WZRfFqVWzzBiLPXTU6eoRJD9moeAOUgDf2Rji6GrlKNQ7p68VFxpwOlM0ABnGjtgkI= 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=209.85.166.77 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-io1-f77.google.com with SMTP id ca18e2360f4ac-7e92491e750so139742239f.1 for ; Sat, 25 May 2024 10:37:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1716658648; x=1717263448; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=e2gxWZWU3yuYPw5fRhn3advDM55MpASJpVtOwXu3qhs=; b=aWXr7opTqd5W2MSa3pDOFzAdTj92iU36ahazBwgRehYnAObBiQkQoNJNAL8kUbtLi5 F97BffFvGFy4yKX9pK6YQVs/t82kaEA1D/6Qbif8mS1l5ldoltjFnoa3TmcQwrE0dOCi PvJqY1CnyplAz56830nwO2Tl1+Yq1t1QhaeX0BxtIsHgmhI8M7QegF6koWSicv8o5c/j /7X0gp8d1zkLKko9Nted5ReeYF3ZT6G/sTqCs8RiH6XV+ingmQEha2L17gYLwNojJeSi 54F6OsCCCtSIHSBk8qi0sZ+lWtFh5zE0Ob24W3CZn76ZyUIDNfVoTvygebxj5D+pNVVK kXqA== X-Forwarded-Encrypted: i=1; AJvYcCWoF9+/BmyTlLEjiOLa+lFLHiGml0TSdNqxg4LUV6NLC7MHwwGwys2FuYotZkiwiRmXRcoC7I0xXyUvYLr0wiItqW1jjhD0 X-Gm-Message-State: AOJu0Yyh9krG5I28b0wSeNPSKYfpgc2V+rJaMOlYz2qotElOQzXf8kkf 02g4+3oem+zCrH7jjZ7kOBq4lAQawcOr1AhfwVtEpRW6WLZB2engRuwiIktBTVrs2a+vXncFJ+O H/vRmVBzNDH4J23iZCH1K3IWlCdtMbkjMjtaRU3FL08J0UNuKuy0Igew= X-Google-Smtp-Source: AGHT+IGTqVwNmwRseGGSTjLyWrYeU5wQgffxKA7M9u9WkDMvKNIwNoGq3kIwVhorxx9hikA4stnrTuFfYxHm1Tgsd1cww0RM5/JA Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a6b:dd07:0:b0:7e2:481e:7dbe with SMTP id ca18e2360f4ac-7e76d31577dmr17655139f.1.1716658648708; Sat, 25 May 2024 10:37:28 -0700 (PDT) Date: Sat, 25 May 2024 10:37:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000f508b006194abc11@google.com> Subject: [syzbot] [net?] WARNING: refcount bug in __netif_napi_del (3) From: syzbot To: davem@davemloft.net, edumazet@google.com, 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: 56fb6f92854f Merge tag 'drm-next-2024-05-25' of https://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14cdd544980000 kernel config: https://syzkaller.appspot.com/x/.config?x=2b8d1faad9ceb620 dashboard link: https://syzkaller.appspot.com/bug?extid=0ba117466149911217d5 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-56fb6f92.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/65ffe3ca9bb3/vmlinux-56fb6f92.xz kernel image: https://storage.googleapis.com/syzbot-assets/354ef77a71b6/bzImage-56fb6f92.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0ba117466149911217d5@syzkaller.appspotmail.com ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 3 PID: 1086 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Modules linked in: CPU: 3 PID: 1086 Comm: kworker/u32:5 Not tainted 6.9.0-syzkaller-12277-g56fb6f92854f #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Workqueue: netns cleanup_net RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28 Code: ff 89 de e8 48 53 0f fd 84 db 0f 85 66 ff ff ff e8 9b 58 0f fd c6 05 56 0f 4d 0b 01 90 48 c7 c7 20 57 8f 8b e8 87 db d1 fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 78 58 0f fd 0f b6 1d 31 0f 4d 0b 31 RSP: 0018:ffffc90006c879d0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81510229 RDX: ffff888020412440 RSI: ffffffff81510236 RDI: 0000000000000001 RBP: ffffe8ffad34d889 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: ffffe8ffad34d889 R13: 0000000000000000 R14: 0000000000000005 R15: ffffe8ffad34d7a5 FS: 0000000000000000(0000) GS:ffff88802c300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f5e79000 CR3: 0000000061526000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __refcount_sub_and_test include/linux/refcount.h:275 [inline] __refcount_dec_and_test include/linux/refcount.h:307 [inline] refcount_dec_and_test include/linux/refcount.h:325 [inline] skb_unref include/linux/skbuff.h:1224 [inline] __kfree_skb_reason net/core/skbuff.c:1195 [inline] kfree_skb_reason+0x1e8/0x210 net/core/skbuff.c:1222 kfree_skb include/linux/skbuff.h:1257 [inline] flush_gro_hash net/core/dev.c:6682 [inline] __netif_napi_del net/core/dev.c:6697 [inline] __netif_napi_del+0x311/0x570 net/core/dev.c:6688 gro_cells_destroy net/core/gro_cells.c:117 [inline] gro_cells_destroy+0x10a/0x4d0 net/core/gro_cells.c:106 ip_tunnel_dev_free+0x19/0x60 net/ipv4/ip_tunnel.c:1100 netdev_run_todo+0x775/0x1250 net/core/dev.c:10692 cleanup_net+0x591/0xbf0 net/core/net_namespace.c:636 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 --- 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