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,URIBL_BLOCKED,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 28572C433DB for ; Fri, 26 Feb 2021 19:12:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E81FC64E21 for ; Fri, 26 Feb 2021 19:12:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230288AbhBZTMX (ORCPT ); Fri, 26 Feb 2021 14:12:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55582 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229967AbhBZTMO (ORCPT ); Fri, 26 Feb 2021 14:12:14 -0500 Received: from mail-lj1-x22f.google.com (mail-lj1-x22f.google.com [IPv6:2a00:1450:4864:20::22f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A469AC061574; Fri, 26 Feb 2021 11:11:33 -0800 (PST) Received: by mail-lj1-x22f.google.com with SMTP id 2so7276791ljr.5; Fri, 26 Feb 2021 11:11:33 -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:mime-version :content-transfer-encoding; bh=IBtIidwVwaIktxepbeCDx/8gfJLnxmhlZEhvJa7e2JM=; b=MoI9sH+xS+N7OBJbwDA0LImxeRrpl7LUczU+TJTygbMNzB22Qdr1WjaavoIxuqpExh ThwGYWvP7XH/yISb2ieM1zg3qlTQItUxEVDiShJB7FQw3d/R7WHAXXHQfPzowbJhQ2eH f/MsMF4UpF4lfPb/3BSVyltleh5h/W34iFaHJ4v/YZw/7tmRABEGfNBG83CwEUymXj8A Wz9AWiHaRd2A0m2LUMxeQE1ertmO8ALzETCNLAyqjY/qL6yL9hDrYFy7sv7bOORmLxoA hHl8RRqffc48Vp3sb+XewfvCvope5o2n0LwyjhmI8fLRkQlpNZ0b7QhVt3bJR4UcKUFG aCAw== 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:mime-version :content-transfer-encoding; bh=IBtIidwVwaIktxepbeCDx/8gfJLnxmhlZEhvJa7e2JM=; b=iDay+iHIZIl+uRZVsQ2tOcicB3tNUmag+lkCgb3MeowOoxcMC8Ng8DrTZcHI9kGOQX xWXD8SJE7plzShgrDyHlMGu9iPY18rmTAJks0RjhEq+mhciI34s5+4rbXmVrqOoy+84z l5/6s6X0i9J4KXVI46GBSuq89Cwly6otxjYBEaePXcyuQOfxc+uAvg/QNaFdJCqI1ig4 8LZmCA+K/ZyWOD2GoDkFJqQpwBAVp1/AYdWd2BQhU9VtBSxc5BitRww/Uc66//A7FzJ4 UPuGYvxlbMTi1eVgZw5N4fYxtG1ah5JnjfDl+T7KiiLsZK5AbL5OPoS0j7G3tOz6oeUH kRSw== X-Gm-Message-State: AOAM533XmSqqpyfNc2yTcrjPmoiwRtJ6ZlvLolkoIgNZVeAsj7904gtE ZLzvw86znKDBoYKZZfMNpUM= X-Google-Smtp-Source: ABdhPJysY0omAmg5k2/lT1pUubT7iOOiWMSX8eFbJyo1D/LcaV3cOa42Hj1XnztgLuDez6RV12a+Cw== X-Received: by 2002:a2e:7f1b:: with SMTP id a27mr2411804ljd.225.1614366692167; Fri, 26 Feb 2021 11:11:32 -0800 (PST) Received: from localhost.localdomain ([94.103.235.59]) by smtp.gmail.com with ESMTPSA id n7sm1472506lfu.123.2021.02.26.11.11.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Feb 2021 11:11:31 -0800 (PST) From: Pavel Skripkin To: davem@davemloft.net, kuba@kernel.org, linmiaohe@huawei.com Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pavel Skripkin , syzbot+80dccaee7c6630fa9dcf@syzkaller.appspotmail.com Subject: [PATCH] net/core/skbuff.c: __netdev_alloc_skb fix when len is greater than KMALLOC_MAX_SIZE Date: Fri, 26 Feb 2021 22:11:06 +0300 Message-Id: <20210226191106.554553-1-paskripkin@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@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. 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 | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 785daff48030..dc28c8f7bf5f 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 (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