main/libssh2: fix for CVE-2019-17498

fixes #10883

2 files changed, 78 insertions, 2 deletions

diff --git a/main/libssh2/APKBUILD b/main/libssh2/APKBUILD
index c87aa6ae9f..6f3b458dd8 100644
--- a/main/libssh2/APKBUILD
+++ b/main/libssh2/APKBUILD
@@ -8,10 +8,13 @@ arch="all"
 license="BSD-3-Clause"
 makedepends="openssl-dev zlib-dev"
 subpackages="$pkgname-dbg $pkgname-static $pkgname-dev $pkgname-doc"
-source="http://www.libssh2.org/download/libssh2-$pkgver.tar.gz"
+source="https://www.libssh2.org/download/libssh2-$pkgver.tar.gz
+        CVE-2019-17498.patch"
 builddir="$srcdir"/libssh2-$pkgver
 
 # security fixes:
+#   1.9.0-r1:
+#     - CVE-2019-17498
 #   1.9.0-r0:
 #     - CVE-2019-13115
 #   1.8.1-r0:
@@ -57,4 +60,5 @@ static() {
         mv "$pkgdir"/usr/lib/*.a "$subpkgdir"/usr/lib
 }
 
-sha512sums="41a3ebcf84e32eab69b7411ffb0a3b6e6db71491c968602b17392cfe3490ef00239726ec28acb3d25bf0ed62700db7f4d0bb5a9175618f413865f40badca6e17  libssh2-1.9.0.tar.gz"
+sha512sums="41a3ebcf84e32eab69b7411ffb0a3b6e6db71491c968602b17392cfe3490ef00239726ec28acb3d25bf0ed62700db7f4d0bb5a9175618f413865f40badca6e17  libssh2-1.9.0.tar.gz
+fedd840ec8459409c80ef3984f3539e09c0730fb1a7ccc8034e3e03618590a5c0589b7dff132c813b148be9f5b784d3cd50830c502d419af77ce86e848297813  CVE-2019-17498.patch"
diff --git a/main/libssh2/CVE-2019-17498.patch b/main/libssh2/CVE-2019-17498.patch
new file mode 100644
index 0000000000..e858cca186
--- /dev/null
+++ b/main/libssh2/CVE-2019-17498.patch
@@ -0,0 +1,72 @@
+From 1c6fa92b77e34d089493fe6d3e2c6c8775858b94 Mon Sep 17 00:00:00 2001
+From: Will Cosgrove <will@panic.com>
+Date: Thu, 29 Aug 2019 15:24:22 -0700
+Subject: [PATCH] fixed type issue, updated SSH_MSG_DISCONNECT
+
+SSH_MSG_DISCONNECT now also uses  _libssh2_get API.
+---
+ src/packet.c | 40 +++++++++++++++-------------------------
+ 1 file changed, 15 insertions(+), 25 deletions(-)
+
+diff --git a/src/packet.c b/src/packet.c
+index 8908b2c5..97f0cdd4 100644
+--- a/src/packet.c
++++ b/src/packet.c
+@@ -419,8 +419,8 @@ _libssh2_packet_add(LIBSSH2_SESSION * session, unsigned char *data,
+                     size_t datalen, int macstate)
+ {
+     int rc = 0;
+-    char *message = NULL;
+-    char *language = NULL;
++    unsigned char *message = NULL;
++    unsigned char *language = NULL;
+     size_t message_len = 0;
+     size_t language_len = 0;
+     LIBSSH2_CHANNEL *channelp = NULL;
+@@ -472,33 +472,23 @@ _libssh2_packet_add(LIBSSH2_SESSION * session, unsigned char *data,
+ 
+         case SSH_MSG_DISCONNECT:
+             if(datalen >= 5) {
+-                size_t reason = _libssh2_ntohu32(data + 1);
++                uint32_t reason = 0;
++                struct string_buf buf;
++                buf.data = (unsigned char *)data;
++                buf.dataptr = buf.data;
++                buf.len = datalen;
++                buf.dataptr++; /* advance past type */
+ 
+-                if(datalen >= 9) {
+-                    message_len = _libssh2_ntohu32(data + 5);
++                _libssh2_get_u32(&buf, &reason);
++                _libssh2_get_string(&buf, &message, &message_len);
++                _libssh2_get_string(&buf, &language, &language_len);
+ 
+-                    if(message_len < datalen-13) {
+-                        /* 9 = packet_type(1) + reason(4) + message_len(4) */
+-                        message = (char *) data + 9;
+-
+-                        language_len =
+-                            _libssh2_ntohu32(data + 9 + message_len);
+-                        language = (char *) data + 9 + message_len + 4;
+-
+-                        if(language_len > (datalen-13-message_len)) {
+-                            /* bad input, clear info */
+-                            language = message = NULL;
+-                            language_len = message_len = 0;
+-                        }
+-                    }
+-                    else
+-                        /* bad size, clear it */
+-                        message_len = 0;
+-                }
+                 if(session->ssh_msg_disconnect) {
+-                    LIBSSH2_DISCONNECT(session, reason, message,
+-                                       message_len, language, language_len);
++                    LIBSSH2_DISCONNECT(session, reason, (const char *)message,
++                                       message_len, (const char *)language,
++                                       language_len);
+                 }
++
+                 _libssh2_debug(session, LIBSSH2_TRACE_TRANS,
+                                "Disconnect(%d): %s(%s)", reason,
+                                message, language);