From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0148EC433DB for ; Sat, 27 Feb 2021 16:40:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD57964E55 for ; Sat, 27 Feb 2021 16:40:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230163AbhB0Qjo (ORCPT ); Sat, 27 Feb 2021 11:39:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230195AbhB0QiX (ORCPT ); Sat, 27 Feb 2021 11:38:23 -0500 Received: from mail-lj1-x235.google.com (mail-lj1-x235.google.com [IPv6:2a00:1450:4864:20::235]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA55AC06174A for ; Sat, 27 Feb 2021 08:37:37 -0800 (PST) Received: by mail-lj1-x235.google.com with SMTP id y12so1329180ljj.12 for ; Sat, 27 Feb 2021 08:37:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2kJ+akVZdN0RZerG3cR+FK9vS9Cr6lCvITb5oXS64J4=; b=fPC02Kq35e/J7JRhNeEX/kO4FeLGB5X3MuEYAHzuDzB7pKmHWsAO/Lmu0Ovypd/hzY 0VCrqTUWIS+3lvEuBaj8sTtL4aLSGsFjMIQWM8K2dYqjus5t38jykw2Ij1jDiic9vgKh ZgSPd6LKTymKLwui4UfQoPTLBMTal4wS65DaHPMYaLqpX8CZz7c4lCVY8FekV3oodGOF tNCu2JsNSq+z7m79lj/c/lQoDEkamvIkQtK2sY6GyDNULUeRu2g/tO54LrpKJoO3qB0A mID0UpaTNqvYqs4w9Bj7LTuObwJTyQybomqixHpxlTiB9Dr8OTaz1N6kSz7lP14VeWvy ltMQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2kJ+akVZdN0RZerG3cR+FK9vS9Cr6lCvITb5oXS64J4=; b=ObOynHlgOnWO1Ca6w8NTCRZiI6pVr6dl8OZLvGsbk2VpWfWuOyuflUrjEx7IXImtVR yAfTeDd+INjmu8ux1Xb2rU0yA1M908scZBSzJScoxpYLJfOiC/jCD+MF6oBSiY+FwFRR S0GH0fYsApRsvH18tBz4Ihb1+pn0q+9AtojnydqTmbxHVFZgA44mL/XOaLWQqUmhS9nb yLM2ZjU7q0v0NTV5K94aO3UKvURhEAIVLeCym2OKjtE6TV23fM35y/rQ9FkhxEekD88v QTQsYDJM7Kh/7CWlJaGkclj20pnH8gd4niGOaFWb1f/MG41J8239HSPfFujbxRj9PYnW BF/A== X-Gm-Message-State: AOAM532iQNIRF2R6DjvjPTAJHGyl0Fle6PX5+qgWRmAgt2if2S+1wFPM Vsw1AThCB56zDyd/xWglh+tzCFfuR+RJ1zrG1W8= X-Google-Smtp-Source: ABdhPJzopzD6I8JNOzZrBvGXbsHaTcPjgQUeh8KBRiKlw9oaXfsXjdj0nJqZB4FFc8tna0qI+LzsHw== X-Received: by 2002:a2e:5c02:: with SMTP id q2mr4606350ljb.81.1614443856122; Sat, 27 Feb 2021 08:37:36 -0800 (PST) Received: from localhost.localdomain ([94.103.235.59]) by smtp.gmail.com with ESMTPSA id c19sm1421401ljk.60.2021.02.27.08.37.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 27 Feb 2021 08:37:35 -0800 (PST) From: Pavel Skripkin Cc: linux-kernel@vger.kernel.org, Pavel Skripkin , syzbot+80dccaee7c6630fa9dcf@syzkaller.appspotmail.com Subject: [PATCH v2] net/core/skbuff: fix passing wrong size to __alloc_skb Date: Sat, 27 Feb 2021 19:35:19 +0300 Message-Id: <20210227163519.18229-1-paskripkin@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210227110306.13360-1-alobakin@pm.me> References: <20210227110306.13360-1-alobakin@pm.me> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot found WARNING in __alloc_pages_nodemask()[1] when order >= MAX_ORDER. It was caused by __netdev_alloc_skb(), which doesn't check len value after adding NET_SKB_PAD. Order will be >= MAX_ORDER and passed to __alloc_pages_nodemask() if size > KMALLOC_MAX_SIZE. Same happens in __napi_alloc_skb. static void *kmalloc_large_node(size_t size, gfp_t flags, int node) { struct page *page; void *ptr = NULL; unsigned int order = get_order(size); ... page = alloc_pages_node(node, flags, order); ... [1] WARNING in __alloc_pages_nodemask+0x5f8/0x730 mm/page_alloc.c:5014 Call Trace: __alloc_pages include/linux/gfp.h:511 [inline] __alloc_pages_node include/linux/gfp.h:524 [inline] alloc_pages_node include/linux/gfp.h:538 [inline] kmalloc_large_node+0x60/0x110 mm/slub.c:3999 __kmalloc_node_track_caller+0x319/0x3f0 mm/slub.c:4496 __kmalloc_reserve net/core/skbuff.c:150 [inline] __alloc_skb+0x4e4/0x5a0 net/core/skbuff.c:210 __netdev_alloc_skb+0x70/0x400 net/core/skbuff.c:446 netdev_alloc_skb include/linux/skbuff.h:2832 [inline] qrtr_endpoint_post+0x84/0x11b0 net/qrtr/qrtr.c:442 qrtr_tun_write_iter+0x11f/0x1a0 net/qrtr/tun.c:98 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x791/0xa30 fs/read_write.c:605 ksys_write+0x12d/0x250 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported-by: syzbot+80dccaee7c6630fa9dcf@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Change-Id: I480a6d6f818a4c0a387db0cd3f230b68a7daeb16 --- net/core/skbuff.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 785daff48030..a35ba145a060 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -443,6 +443,9 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len, if (len <= SKB_WITH_OVERHEAD(1024) || len > SKB_WITH_OVERHEAD(PAGE_SIZE) || (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) { + if (unlikely(len > KMALLOC_MAX_SIZE)) + return NULL; + skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX, NUMA_NO_NODE); if (!skb) goto skb_fail; @@ -517,6 +520,9 @@ struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len, if (len <= SKB_WITH_OVERHEAD(1024) || len > SKB_WITH_OVERHEAD(PAGE_SIZE) || (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) { + if (unlikely(len > KMALLOC_MAX_SIZE)) + return NULL; + skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX, NUMA_NO_NODE); if (!skb) goto skb_fail; -- 2.25.1