From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELstgCR9hr7QDg437intQILsfKSHifgaHqSkSNyHE5dIMfCFxun2x07wbCqCFgDobnk5w6oV ARC-Seal: i=1; a=rsa-sha256; t=1521214340; cv=none; d=google.com; s=arc-20160816; b=Mg5HbO6uOYYQNMCv1Hc1TetNPbpj9CJezAnQH38v83BJIbB59mHixIUT6fnGo0Fzqa szrLE2nr0V+428vwoxK+PgmfdUDqc5E6iWoMMhLE7WxnlF4Ka66drbI7tl11yfVQkRrO Y+8UD6Efq7MaYkiOHl2SbGej4gpNp6XgaGPsNNnYP976iz7WDqM0pUPNwOkY9l9aPc6W IkDQ3sAcxfophp0Tn95kbtf08KZ2mc3EcBBeZDU8CrDE1hyvkyxOvTLa3xkoQQddqw4N mQY5RwfsLeh8GARfohZ+zAA35KN/3LqavXPXKRPXcqTynWgQNVxkedrUBcQpX6dKLonh TF8g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=7ouNjhqoCzSXQArjlUPp4t52NNJU82baUjdc1rBNHKo=; b=sA7tNkVVkgCKoM9SaBCv2U1HbstLmIPqGyfLEGXvDYnbSqZbIYGrN52TF6jochxORk 3HSUOjR8yRDES1/q+EMyj9EVUh21i30vXV4srNFtlVeOVowM/X9Z0SC/LeFGOM5XWb77 teA7ZblzRiv7vaLdFKoO6idpBFQ7/f4bb34KQpzxzQJHotAOREiOQxZNl4W+sNBTIAK/ 8k/Nz5Q3a6CdpBDXNlX41yP65NeOkYbTE1b/grrpLWMx/oCnxU3cdaETGpmWt62eQFdB /rRbozft6FVhB/sRkngcfV6Xjr2f5VFc4alX/XqByHsZrDyhsA/uSL5pdYvCDsKqLoO5 BSRA== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Florian Westphal , Pablo Neira Ayuso Subject: [PATCH 4.9 60/86] netfilter: ipv6: fix use-after-free Write in nf_nat_ipv6_manip_pkt Date: Fri, 16 Mar 2018 16:23:23 +0100 Message-Id: <20180316152321.434548741@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180316152317.167709497@linuxfoundation.org> References: <20180316152317.167709497@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1595108478397273655?= X-GMAIL-MSGID: =?utf-8?q?1595108848363083660?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Westphal commit b078556aecd791b0e5cb3a59f4c3a14273b52121 upstream. l4proto->manip_pkt() can cause reallocation of skb head so pointer to the ipv6 header must be reloaded. Reported-and-tested-by: Fixes: 58a317f1061c89 ("netfilter: ipv6: add IPv6 NAT support") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c @@ -99,6 +99,10 @@ static bool nf_nat_ipv6_manip_pkt(struct !l4proto->manip_pkt(skb, &nf_nat_l3proto_ipv6, iphdroff, hdroff, target, maniptype)) return false; + + /* must reload, offset might have changed */ + ipv6h = (void *)skb->data + iphdroff; + manip_addr: if (maniptype == NF_NAT_MANIP_SRC) ipv6h->saddr = target->src.u3.in6;