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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 147CBC433EF for ; Mon, 14 Mar 2022 09:24:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237916AbiCNJZ5 (ORCPT ); Mon, 14 Mar 2022 05:25:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231899AbiCNJZ4 (ORCPT ); Mon, 14 Mar 2022 05:25:56 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A92572B197 for ; Mon, 14 Mar 2022 02:24:47 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4518860916 for ; Mon, 14 Mar 2022 09:24:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0CB06C340E9; Mon, 14 Mar 2022 09:24:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1647249886; bh=AgeUCg/QA7PLHvFidg9JXn7nGbLYW7vuOBG0lQU7ZLo=; h=Subject:To:Cc:From:Date:From; b=GTW3GJCOwfDgbAV4Zq1UxoqeaWrWVg8sCbXnFzLNYOrwlbZmU/uo92mxRoz7JTPJH IcTmDoRGt63eytWZCYrUaPjiKHRAIyWiYgaS9hw4d8To8lA35smZu8F5xF5Vis66AU hcFt61rVqypv3CGjMFwgXrI6x5edyXUEzEfVuKHI= Subject: FAILED: patch "[PATCH] esp: Fix possible buffer overflow in ESP transformation" failed to apply to 4.19-stable tree To: steffen.klassert@secunet.com, sec@valis.email Cc: From: Date: Mon, 14 Mar 2022 10:24:34 +0100 Message-ID: <164724987424249@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From ebe48d368e97d007bfeb76fcb065d6cfc4c96645 Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Mon, 7 Mar 2022 13:11:39 +0100 Subject: [PATCH] esp: Fix possible buffer overflow in ESP transformation The maximum message size that can be send is bigger than the maximum site that skb_page_frag_refill can allocate. So it is possible to write beyond the allocated buffer. Fix this by doing a fallback to COW in that case. v2: Avoid get get_order() costs as suggested by Linus Torvalds. Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible") Reported-by: valis Signed-off-by: Steffen Klassert diff --git a/include/net/esp.h b/include/net/esp.h index 9c5637d41d95..90cd02ff77ef 100644 --- a/include/net/esp.h +++ b/include/net/esp.h @@ -4,6 +4,8 @@ #include +#define ESP_SKB_FRAG_MAXSIZE (PAGE_SIZE << SKB_FRAG_PAGE_ORDER) + struct ip_esp_hdr; static inline struct ip_esp_hdr *ip_esp_hdr(const struct sk_buff *skb) diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index e1b1d080e908..70e6c87fbe3d 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -446,6 +446,7 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * struct page *page; struct sk_buff *trailer; int tailen = esp->tailen; + unsigned int allocsz; /* this is non-NULL only with TCP/UDP Encapsulation */ if (x->encap) { @@ -455,6 +456,10 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * return err; } + allocsz = ALIGN(skb->data_len + tailen, L1_CACHE_BYTES); + if (allocsz > ESP_SKB_FRAG_MAXSIZE) + goto cow; + if (!skb_cloned(skb)) { if (tailen <= skb_tailroom(skb)) { nfrags = 1; diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c index 7591160edce1..b0ffbcd5432d 100644 --- a/net/ipv6/esp6.c +++ b/net/ipv6/esp6.c @@ -482,6 +482,7 @@ int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info struct page *page; struct sk_buff *trailer; int tailen = esp->tailen; + unsigned int allocsz; if (x->encap) { int err = esp6_output_encap(x, skb, esp); @@ -490,6 +491,10 @@ int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info return err; } + allocsz = ALIGN(skb->data_len + tailen, L1_CACHE_BYTES); + if (allocsz > ESP_SKB_FRAG_MAXSIZE) + goto cow; + if (!skb_cloned(skb)) { if (tailen <= skb_tailroom(skb)) { nfrags = 1;