Unbreak Unix domain socket forwarding for root (closes: #858252).

2 files changed, 81 insertions, 0 deletions

diff --git a/debian/patches/series b/debian/patches/series
index 32f913e89..c5fc81486 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -33,3 +33,4 @@ restore-authorized_keys2.patch
 ssh-keygen-hash-corruption.patch
 ssh-keyscan-hash-port.patch
 ssh-keygen-null-deref.patch
+unbreak-unix-forwarding-for-root.patch
diff --git a/debian/patches/unbreak-unix-forwarding-for-root.patch b/debian/patches/unbreak-unix-forwarding-for-root.patch
new file mode 100644
index 000000000..8408a118a
--- /dev/null
+++ b/debian/patches/unbreak-unix-forwarding-for-root.patch
@@ -0,0 +1,80 @@
+From 904bc482ad87648a2c799c441dc6a8449f24e15a Mon Sep 17 00:00:00 2001
+From: "djm@openbsd.org" <djm@openbsd.org>
+Date: Wed, 4 Jan 2017 05:37:40 +0000
+Subject: upstream commit
+
+unbreak Unix domain socket forwarding for root; ok
+markus@
+
+Upstream-ID: 6649c76eb7a3fa15409373295ca71badf56920a2
+
+Origin: https://anongit.mindrot.org/openssh.git/commit/?id=51045869fa084cdd016fdd721ea760417c0a3bf3
+Bug-Debian: https://bugs.debian.org/858252
+Last-Update: 2017-03-30
+
+Patch-Name: unbreak-unix-forwarding-for-root.patch
+---
+ serverloop.c | 19 ++++++++++++-------
+ 1 file changed, 12 insertions(+), 7 deletions(-)
+
+diff --git a/serverloop.c b/serverloop.c
+index c4e4699d..c55d203b 100644
+--- a/serverloop.c
++++ b/serverloop.c
+@@ -468,6 +468,10 @@ server_request_direct_streamlocal(void)
+        Channel *c = NULL;
+        char *target, *originator;
+        u_short originator_port;
++       struct passwd *pw = the_authctxt->pw;
++
++       if (pw == NULL || !the_authctxt->valid)
++               fatal("server_input_global_request: no/invalid user");
+ 
+        target = packet_get_string(NULL);
+        originator = packet_get_string(NULL);
+@@ -480,7 +484,7 @@ server_request_direct_streamlocal(void)
+        /* XXX fine grained permissions */
+        if ((options.allow_streamlocal_forwarding & FORWARD_LOCAL) != 0 &&
+            !no_port_forwarding_flag && !options.disable_forwarding &&
+-           use_privsep) {
++           (pw->pw_uid == 0 || use_privsep)) {
+                c = channel_connect_to_path(target,
+                    "direct-streamlocal@openssh.com", "direct-streamlocal");
+        } else {
+@@ -702,6 +706,10 @@ server_input_global_request(int type, u_int32_t seq, void *ctxt)
+        int want_reply;
+        int r, success = 0, allocated_listen_port = 0;
+        struct sshbuf *resp = NULL;
++       struct passwd *pw = the_authctxt->pw;
++
++       if (pw == NULL || !the_authctxt->valid)
++               fatal("server_input_global_request: no/invalid user");
+ 
+        rtype = packet_get_string(NULL);
+        want_reply = packet_get_char();
+@@ -709,12 +717,8 @@ server_input_global_request(int type, u_int32_t seq, void *ctxt)
+ 
+        /* -R style forwarding */
+        if (strcmp(rtype, "tcpip-forward") == 0) {
+-               struct passwd *pw;
+                struct Forward fwd;
+ 
+-               pw = the_authctxt->pw;
+-               if (pw == NULL || !the_authctxt->valid)
+-                       fatal("server_input_global_request: no/invalid user");
+                memset(&fwd, 0, sizeof(fwd));
+                fwd.listen_host = packet_get_string(NULL);
+                fwd.listen_port = (u_short)packet_get_int();
+@@ -762,9 +766,10 @@ server_input_global_request(int type, u_int32_t seq, void *ctxt)
+                /* check permissions */
+                if ((options.allow_streamlocal_forwarding & FORWARD_REMOTE) == 0
+                    || no_port_forwarding_flag || options.disable_forwarding ||
+-                   !use_privsep) {
++                   (pw->pw_uid != 0 && !use_privsep)) {
+                        success = 0;
+-                       packet_send_debug("Server has disabled port forwarding.");
++                       packet_send_debug("Server has disabled "
++                           "streamlocal forwarding.");
+                } else {
+                        /* Start listening on the socket */
+                        success = channel_setup_remote_fwd_listener(