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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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=unavailable 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 807B6C433E0 for ; Sat, 27 Feb 2021 16:43:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5BCD364E56 for ; Sat, 27 Feb 2021 16:43:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230203AbhB0Qn2 (ORCPT ); Sat, 27 Feb 2021 11:43:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230211AbhB0QmG (ORCPT ); Sat, 27 Feb 2021 11:42:06 -0500 Received: from mail-lj1-x22b.google.com (mail-lj1-x22b.google.com [IPv6:2a00:1450:4864:20::22b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E671C06174A; Sat, 27 Feb 2021 08:41:24 -0800 (PST) Received: by mail-lj1-x22b.google.com with SMTP id k12so5244140ljg.9; Sat, 27 Feb 2021 08:41:24 -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=FsE8+G6D3CJ417+4kZs5yOR5XZsmI4X4DTVrqshFXL0ob3/OO8x5woXqypXEcutF3m oDNT7bD7lCTFMBKhv1GISBXNfg/wr40fp7Xn3eVnY8cP/niOa6cEZd33LC0rMIfrdpMJ J0MpgG+D8dCBF2hN47qaICc8AFU9xtY+g50RL5U++JMxagZKoLgoqMGh9iv7B8joDty+ SZh7PO2mU/N7Vh4mlmmKXTQq8RsMbFOq31t+wEV5QparW20FQsqL/2U9Y7DTD72pDOnB 7eDHxQnUbIxtL9lKNpqqRuFheUt/MikEWh6UEquMunAFTXNY+tdaoNo3s9JerY7ljnb+ OKgw== 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=EFXJIugqQajo8kuk7R8tza3sZxN0e9sP7rtQOUc4rN+74G4UG7icuFxP4N7Tb/FoMs OlzInRzKWY84tpNvWeYv8O+svhxvw0opJoMB7Tgp8GXj+iGW2v63xKGDob46EW6jkGcz zq5DXDrNrqbDeg8kXjHHRwMJlF7G8LshBHu9ndNLG2E5xbKmex7ERlMynjXp/mfS1jCW 2IVK2wie4NuTf3HPxDYWvfEtxuwKnJKSHodl3AKr/7hk6svDcFHwA6nhlhIOCFnyAXZC WcFRmo76MxGG5QH4LaeThKz2Og0m+pZalCeXGhxzT+u12d+tGILcS0RUQpkDrX3Gg+Uo W6DQ== X-Gm-Message-State: AOAM5319CcX6pUHm7BloqmzqKvD7Sn9kPVR8bnPGiK43z4aEh2MK+nFY 6QrhMn2eA/TjThxZaQEAqZw= X-Google-Smtp-Source: ABdhPJxFCszFUea7FawYs/6SUHk8XvOJQTlQBLwm+ULp1tyXV41NJYMQqRJshbMYfK9sLoUxG1JQoA== X-Received: by 2002:a05:651c:229:: with SMTP id z9mr4839872ljn.267.1614444082640; Sat, 27 Feb 2021 08:41:22 -0800 (PST) Received: from localhost.localdomain ([94.103.235.59]) by smtp.gmail.com with ESMTPSA id q16sm1726626lfu.153.2021.02.27.08.41.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 27 Feb 2021 08:41:22 -0800 (PST) From: Pavel Skripkin To: alobakin@pm.me Cc: linux-kernel@vger.kernel.org, davem@davemloft.net, linmiaohe@huawei.com, netdev@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 19:41:01 +0300 Message-Id: <20210227164101.19071-1-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 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