From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELsmmqiPzCRlsvl8faSyF75hru5vZQS6gmXmvKl2cgNKv77jB7os4ZH1UikwjETK7w3ETAO9 ARC-Seal: i=1; a=rsa-sha256; t=1519412242; cv=none; d=google.com; s=arc-20160816; b=FsFKoE3l6MUGUqQEOh97cM7VTCwU2lWeD2sx9tdsLigd3Wu/yGVblXFlEZVCrm+7Lw C8YMsLwysSX/vcfwJMmB+NqMiXEo9CWgD+wKZ3jjziIMwLoXr8iq6OfmwnJzBpLeLHpx gU8b3dc0OtLymteBB2wR44foejE4lYeh450LlgFRquZ8yTcsSdJkAQKxFP9exDCg8sJd 0RQ8EtDq4W4eaRAOCaxB4MmOTJYBzGmIMFtj2lY2LrFJjcB7jyDTwCafkYwpXkzelhnz KK9AXBFYa7FwuL6sOpEcRiQqp40pNBUg9GvQVHmGwRn0Lj2sPOcCo1jSeS7qW204hbM4 E4uA== 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=gj8ov2eCxDHkZimj6p2+Q0h4ARE7MW/wcrJyHG0vqeI=; b=gHKqsmt4ngVF1JN14m4NkqDI0cruTpJdIac00j8c5Xq9rEGGoSObX3EvFGecmHocgQ WzxtBg6XNNPCpTIfrv8dT21XDDZxwOb+TacaIp6mo6PsrebrjR3rebLj0gXJIXv4vLNi +kqEFKGensrEqmW6153ufIqGdDd3TJ1ajZHS91txJhJg1sqMvb4KupDygx3nK5vQMvH0 0r9cRZ+oPjEd2kRtqWc30iZ1Wsa6bcWdEFSKHZr9dE7BRlOyDbN8718ktwbAhXKGXEtT ab1Gkwun77taXY2D+Vme8N4/Kqu9Piy9UnxQNIJICplcF0cG7ieDHmLi4Go+wjovvYqp fugA== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 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 90.92.71.90 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, Eric Dumazet , syzbot , Florian Westphal , Pablo Neira Ayuso Subject: [PATCH 4.15 14/45] netfilter: x_tables: avoid out-of-bounds reads in xt_request_find_{match|target} Date: Fri, 23 Feb 2018 19:28:53 +0100 Message-Id: <20180223170717.611089900@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180223170715.197760019@linuxfoundation.org> References: <20180223170715.197760019@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?1593217537889132709?= X-GMAIL-MSGID: =?utf-8?q?1593219211556132883?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet commit da17c73b6eb74aad3c3c0654394635675b623b3e upstream. It looks like syzbot found its way into netfilter territory. Issue here is that @name comes from user space and might not be null terminated. Out-of-bound reads happen, KASAN is not happy. v2 added similar fix for xt_request_find_target(), as Florian advised. Signed-off-by: Eric Dumazet Reported-by: syzbot Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman --- net/netfilter/x_tables.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -209,6 +209,9 @@ xt_request_find_match(uint8_t nfproto, c { struct xt_match *match; + if (strnlen(name, XT_EXTENSION_MAXNAMELEN) == XT_EXTENSION_MAXNAMELEN) + return ERR_PTR(-EINVAL); + match = xt_find_match(nfproto, name, revision); if (IS_ERR(match)) { request_module("%st_%s", xt_prefix[nfproto], name); @@ -251,6 +254,9 @@ struct xt_target *xt_request_find_target { struct xt_target *target; + if (strnlen(name, XT_EXTENSION_MAXNAMELEN) == XT_EXTENSION_MAXNAMELEN) + return ERR_PTR(-EINVAL); + target = xt_find_target(af, name, revision); if (IS_ERR(target)) { request_module("%st_%s", xt_prefix[af], name);