[dunfell,02/20] connman: fix CVE-2022-23096-7

Message ID b8d925c1443c84500df74958aa2f75113b992453.1645452535.git.steve@sakoman.com
State Accepted, archived
Commit b8d925c1443c84500df74958aa2f75113b992453
Headers show
Series [dunfell,01/20] expat: fix CVE-2022-23990 | expand

Commit Message

Steve Sakoman Feb. 21, 2022, 2:14 p.m. UTC
An issue was discovered in the DNS proxy in Connman through 1.40.
The TCP server reply implementation lacks a check for the presence
of sufficient Header Data, leading to an out-of-bounds read (CVE-2022-23096)

An issue was discovered in the DNS proxy in Connman through 1.40.
forward_dns_reply mishandles a strnlen call, leading to an out-of-bounds
read (CVE-2022-23097)

Backport patch from:
https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=e5a313736e13c90d19085e953a26256a198e4950

CVE: CVE-2022-23096 CVE-2022-23097

Signed-off-by: Steve Sakoman
---
 .../connman/connman/CVE-2022-23096-7.patch    | 121 ++++++++++++++++++
 .../connman/connman_1.37.bb                   |   1 +
 2 files changed, 122 insertions(+)
 create mode 100644 meta/recipes-connectivity/connman/connman/CVE-2022-23096-7.patch

Patch

diff --git a/meta/recipes-connectivity/connman/connman/CVE-2022-23096-7.patch b/meta/recipes-connectivity/connman/connman/CVE-2022-23096-7.patch
new file mode 100644
index 0000000000..7f27474830
--- /dev/null
+++ b/meta/recipes-connectivity/connman/connman/CVE-2022-23096-7.patch
@@ -0,0 +1,121 @@ 
+From e5a313736e13c90d19085e953a26256a198e4950 Mon Sep 17 00:00:00 2001
+From: Daniel Wagner <wagi@monom.org>
+Date: Tue, 25 Jan 2022 10:00:24 +0100
+Subject: dnsproxy: Validate input data before using them
+
+dnsproxy is not validating various input data. Add a bunch of checks.
+
+Fixes: CVE-2022-23097
+Fixes: CVE-2022-23096
+
+Upstream-Status: Backport
+https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=e5a313736e13c90d19085e953a26256a198e4950
+
+CVE: CVE-2022-23096 CVE-2022-23097
+Signed-off-by: Steve Sakoman <steve@sakoman.com>
+
+---
+ src/dnsproxy.c | 31 ++++++++++++++++++++++++++-----
+ 1 file changed, 26 insertions(+), 5 deletions(-)
+
+diff --git a/src/dnsproxy.c b/src/dnsproxy.c
+index cdfafbc2..c027bcb9 100644
+--- a/src/dnsproxy.c
++++ b/src/dnsproxy.c
+@@ -1951,6 +1951,12 @@ static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol,
+ 
+ 	if (offset < 0)
+ 		return offset;
++	if (reply_len < 0)
++		return -EINVAL;
++	if (reply_len < offset + 1)
++		return -EINVAL;
++	if ((size_t)reply_len < sizeof(struct domain_hdr))
++		return -EINVAL;
+ 
+ 	hdr = (void *)(reply + offset);
+ 	dns_id = reply[offset] | reply[offset + 1] << 8;
+@@ -1986,23 +1992,31 @@ static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol,
+ 		 */
+ 		if (req->append_domain && ntohs(hdr->qdcount) == 1) {
+ 			uint16_t domain_len = 0;
+-			uint16_t header_len;
++			uint16_t header_len, payload_len;
+ 			uint16_t dns_type, dns_class;
+ 			uint8_t host_len, dns_type_pos;
+ 			char uncompressed[NS_MAXDNAME], *uptr;
+ 			char *ptr, *eom = (char *)reply + reply_len;
++			char *domain;
+ 
+ 			/*
+ 			 * ptr points to the first char of the hostname.
+ 			 * ->hostname.domain.net
+ 			 */
+ 			header_len = offset + sizeof(struct domain_hdr);
++			if (reply_len < header_len)
++				return -EINVAL;
++			payload_len = reply_len - header_len;
++
+ 			ptr = (char *)reply + header_len;
+ 
+ 			host_len = *ptr;
++			domain = ptr + 1 + host_len;
++			if (domain > eom)
++				return -EINVAL;
++
+ 			if (host_len > 0)
+-				domain_len = strnlen(ptr + 1 + host_len,
+-						reply_len - header_len);
++				domain_len = strnlen(domain, eom - domain);
+ 
+ 			/*
+ 			 * If the query type is anything other than A or AAAA,
+@@ -2011,6 +2025,8 @@ static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol,
+ 			 */
+ 			dns_type_pos = host_len + 1 + domain_len + 1;
+ 
++			if (ptr + (dns_type_pos + 3) > eom)
++				return -EINVAL;
+ 			dns_type = ptr[dns_type_pos] << 8 |
+ 							ptr[dns_type_pos + 1];
+ 			dns_class = ptr[dns_type_pos + 2] << 8 |
+@@ -2040,6 +2056,8 @@ static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol,
+ 				int new_len, fixed_len;
+ 				char *answers;
+ 
++				if (len > payload_len)
++					return -EINVAL;
+ 				/*
+ 				 * First copy host (without domain name) into
+ 				 * tmp buffer.
+@@ -2054,6 +2072,8 @@ static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol,
+ 				 * Copy type and class fields of the question.
+ 				 */
+ 				ptr += len + domain_len + 1;
++				if (ptr + NS_QFIXEDSZ > eom)
++					return -EINVAL;
+ 				memcpy(uptr, ptr, NS_QFIXEDSZ);
+ 
+ 				/*
+@@ -2063,6 +2083,8 @@ static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol,
+ 				uptr += NS_QFIXEDSZ;
+ 				answers = uptr;
+ 				fixed_len = answers - uncompressed;
++				if (ptr + offset > eom)
++					return -EINVAL;
+ 
+ 				/*
+ 				 * We then uncompress the result to buffer
+@@ -2257,8 +2279,7 @@ static gboolean udp_server_event(GIOChannel *channel, GIOCondition condition,
+ 
+ 	len = recv(sk, buf, sizeof(buf), 0);
+ 
+-	if (len >= 12)
+-		forward_dns_reply(buf, len, IPPROTO_UDP, data);
++	forward_dns_reply(buf, len, IPPROTO_UDP, data);
+ 
+ 	return TRUE;
+ }
+-- 
+cgit 1.2.3-1.el7
+
diff --git a/meta/recipes-connectivity/connman/connman_1.37.bb b/meta/recipes-connectivity/connman/connman_1.37.bb
index bdab4c4f18..e3ea3cd065 100644
--- a/meta/recipes-connectivity/connman/connman_1.37.bb
+++ b/meta/recipes-connectivity/connman/connman_1.37.bb
@@ -9,6 +9,7 @@  SRC_URI  = "${KERNELORG_MIRROR}/linux/network/${BPN}/${BP}.tar.xz \
             file://CVE-2021-26675.patch \
             file://CVE-2021-26676-0001.patch \
             file://CVE-2021-26676-0002.patch \
+            file://CVE-2022-23096-7.patch \
 "
 
 SRC_URI_append_libc-musl = " file://0002-resolve-musl-does-not-implement-res_ninit.patch"