From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f49.google.com (mail-ot1-f49.google.com [209.85.210.49]) (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 B8645481D3 for ; Mon, 5 Feb 2024 18:59:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.49 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707159583; cv=none; b=cICG1lNrXN1k/UeKBWzDKSW6hhSlC+IPLSF4vN50Qk1D0xbXPzS2rnA70s+pm11i/s+g7Z3gK8+RVfl9RJGbDJ62hHecPURVRg8/a6/QUCCdYkZKvwepZkGnguHbojKlZ8DZi4FZGp7+kEpTjaxtlSVErrLDDNwDwOskoyhx/uA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707159583; c=relaxed/simple; bh=L6J91ZwtQxJs7VebFqQJ1XGDU9Pzok5b5HvYlaSib1c=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: Mime-Version:Content-Type; b=aalIuPzTXRcSqwWipaLoc/ufojnhWZ6Miu5ivFgUpCKoAEerfncPYTFzUE6T5pB/Bib17HI0FbO5Qeqv0AYgkGx2lG1yAtxKjrvxssrqFfvAqbFE+//aZpk+CYFgwLRrU2JIXM57RRqUOMzc1BjxIETh7Xtb2eiJgzc4k/WYfk0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=THAfD0+k; arc=none smtp.client-ip=209.85.210.49 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="THAfD0+k" Received: by mail-ot1-f49.google.com with SMTP id 46e09a7af769-6e118b528aeso2336473a34.1 for ; Mon, 05 Feb 2024 10:59:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1707159581; x=1707764381; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=SNVfzD3OEZrVNN2/snO06E/YiW0rpsU7ImFMjbgDBjI=; b=THAfD0+kpodaJyayeNEUkTBmAFqH4o6VPxQViY8XKxjkfuxqgagIiXLEIV7AxzRM6t h/NP5C0Xw/Afa85qb9UrvuasQUiXJDf86U1a1BQgMXwPSDTxSgIcd0fsW7Xlv6GCjsn5 y8p9cEiEbY+uWYCzNf66QvDus1nUvXeXALjvUyknwUo6/l7FkssFk5kuRAbnSTiMmrQK 94BwLZkyeaKR4GqSwVdI2J+C9T4dhQ93OtwZx5rRLMkBrBInRomhcMQw1imlaUaCzUQ/ 2G8NGmA5RGQMEbY7N9PE9y5a/Gpo27m9uLPd0gUspR1VnQ8dFhnMWOp497WPkMAcgNZn kCjw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707159581; x=1707764381; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=SNVfzD3OEZrVNN2/snO06E/YiW0rpsU7ImFMjbgDBjI=; b=CqPVEOBsm3DxA1b30CgAE8fX4A/x0KJ5jsWPmzh4seG+89/SFJaLCuYc4Rg0upCdad jb0JPFzxfFzr3+SexlBk3nYIfcoxCrM6HTrHM5ft3eyebALyN9pVLsRKS8bvMSG0A0/r c6TLDTtGeVVsBUEaGSaIG73hda+zenRynbMS17PgOwVQpwkm9KE2SDeTk+O0kpTzEnwZ zmPvnaAQwSW48QRNPt09vLgDLkxJoPqIFRhxZFFdigGwzrIuM5r1+ViKOraUEQ6qWupo ks6C/TE/BKKVkKtilnxDgbTmA26+51QdAVFsRi12HO7AH2obRj5uaXQ7R2z6RiAFQqsK 6POw== X-Gm-Message-State: AOJu0Ywk8Qdkx+vGKFwEscpuDQTw5ulEd3VSbCZkynhe0WKy/CPEzXeL M8Yh15D8K+u0bVlJy15e0Ga4lss9fqjgDVgdIvm36aMTJsxNTyn4 X-Google-Smtp-Source: AGHT+IFqyHkKIXTArzvlDRQ01POz0ruzb4OpNJVci+uSkhGXP4fcbdAKskwaYNGlYz6fz5Sinh88Fg== X-Received: by 2002:a05:6830:3111:b0:6dd:e530:8c12 with SMTP id b17-20020a056830311100b006dde5308c12mr708861ots.4.1707159580704; Mon, 05 Feb 2024 10:59:40 -0800 (PST) X-Forwarded-Encrypted: i=0; AJvYcCXRJwECdsJeN0+PZjSbEzLzpUEv7bFv9/el9vYT2UJ3nwho5OnV68durLiBKNGHs+7rMg82SJGEBk08BP7yPr9Y4jCuXuwgdZQiPmkIqayZmrHFIF5sjLV/ZD52aFMyhOeS4xs2l45PQ1h1ZGLWUGj68B00dgCnCt0qLITYnFGjSFb/0uxcOP+zTL7JyRT/ZyJGclNTisTRNpYFmg4QDHcyPVPyu6XGG3nOUfzxtk0oCdocyTN1NiNEFnN9xhA15BKaK4VG1ie9m6Xg Received: from localhost (131.65.194.35.bc.googleusercontent.com. [35.194.65.131]) by smtp.gmail.com with ESMTPSA id ku23-20020a05622a0a9700b0042c20fcbac1sm201517qtb.41.2024.02.05.10.59.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Feb 2024 10:59:40 -0800 (PST) Date: Mon, 05 Feb 2024 13:59:40 -0500 From: Willem de Bruijn To: Eric Dumazet , "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , syzbot+c5da1f087c9e4ec6c933@syzkaller.appspotmail.com, Willem de Bruijn Message-ID: <65c1301c2fc9c_7b2e029449@willemb.c.googlers.com.notmuch> In-Reply-To: <20240205171004.1059724-1-edumazet@google.com> References: <20240205171004.1059724-1-edumazet@google.com> Subject: Re: [PATCH net] ppp_async: limit MRU to 64K Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Eric Dumazet wrote: > syzbot triggered a warning [1] in __alloc_pages(): > > WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp) > > Willem fixed a similar issue in commit c0a2a1b0d631 ("ppp: limit MRU to 64K") > > Adopt the same sanity check for ppp_async_ioctl(PPPIOCSMRU) > > [1]: > > WARNING: CPU: 1 PID: 11 at mm/page_alloc.c:4543 __alloc_pages+0x308/0x698 mm/page_alloc.c:4543 > Modules linked in: > CPU: 1 PID: 11 Comm: kworker/u4:0 Not tainted 6.8.0-rc2-syzkaller-g41bccc98fb79 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 > Workqueue: events_unbound flush_to_ldisc > pstate: 204000c5 (nzCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : __alloc_pages+0x308/0x698 mm/page_alloc.c:4543 > lr : __alloc_pages+0xc8/0x698 mm/page_alloc.c:4537 > sp : ffff800093967580 > x29: ffff800093967660 x28: ffff8000939675a0 x27: dfff800000000000 > x26: ffff70001272ceb4 x25: 0000000000000000 x24: ffff8000939675c0 > x23: 0000000000000000 x22: 0000000000060820 x21: 1ffff0001272ceb8 > x20: ffff8000939675e0 x19: 0000000000000010 x18: ffff800093967120 > x17: ffff800083bded5c x16: ffff80008ac97500 x15: 0000000000000005 > x14: 1ffff0001272cebc x13: 0000000000000000 x12: 0000000000000000 > x11: ffff70001272cec1 x10: 1ffff0001272cec0 x9 : 0000000000000001 > x8 : ffff800091c91000 x7 : 0000000000000000 x6 : 000000000000003f > x5 : 00000000ffffffff x4 : 0000000000000000 x3 : 0000000000000020 > x2 : 0000000000000008 x1 : 0000000000000000 x0 : ffff8000939675e0 > Call trace: > __alloc_pages+0x308/0x698 mm/page_alloc.c:4543 > __alloc_pages_node include/linux/gfp.h:238 [inline] > alloc_pages_node include/linux/gfp.h:261 [inline] > __kmalloc_large_node+0xbc/0x1fc mm/slub.c:3926 > __do_kmalloc_node mm/slub.c:3969 [inline] > __kmalloc_node_track_caller+0x418/0x620 mm/slub.c:4001 > kmalloc_reserve+0x17c/0x23c net/core/skbuff.c:590 > __alloc_skb+0x1c8/0x3d8 net/core/skbuff.c:651 > __netdev_alloc_skb+0xb8/0x3e8 net/core/skbuff.c:715 > netdev_alloc_skb include/linux/skbuff.h:3235 [inline] > dev_alloc_skb include/linux/skbuff.h:3248 [inline] > ppp_async_input drivers/net/ppp/ppp_async.c:863 [inline] > ppp_asynctty_receive+0x588/0x186c drivers/net/ppp/ppp_async.c:341 > tty_ldisc_receive_buf+0x12c/0x15c drivers/tty/tty_buffer.c:390 > tty_port_default_receive_buf+0x74/0xac drivers/tty/tty_port.c:37 > receive_buf drivers/tty/tty_buffer.c:444 [inline] > flush_to_ldisc+0x284/0x6e4 drivers/tty/tty_buffer.c:494 > process_one_work+0x694/0x1204 kernel/workqueue.c:2633 > process_scheduled_works kernel/workqueue.c:2706 [inline] > worker_thread+0x938/0xef4 kernel/workqueue.c:2787 > kthread+0x288/0x310 kernel/kthread.c:388 > ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Reported-and-tested-by: syzbot+c5da1f087c9e4ec6c933@syzkaller.appspotmail.com > Signed-off-by: Eric Dumazet > Cc: Willem de Bruijn Reviewed-by: Willem de Bruijn