samba36: fix some security problems

This Adds fixes for the following security problems based on debians patches:
CVE-2016-2125: Unconditional privilege delegation to Kerberos servers in trusted realms
CVE-2017-12163: Server memory information leak over SMB1
CVE-2017-12150: SMB1/2/3 connections may not require signing where they should
CVE-2018-1050: Denial of Service Attack on external print server.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

package/network/services/samba36/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=samba
 PKG_VERSION:=3.6.25
-PKG_RELEASE:=9
+PKG_RELEASE:=10
 
 PKG_SOURCE_URL:=https://download.samba.org/pub/samba \
 		https://download.samba.org/pub/samba/stable

package/network/services/samba36/patches/028-CVE-2016-2125-v3.6.patch

@@ -0,0 +1,59 @@
+From: =?utf-8?q?Guido_G=C3=BCnther?= <agx@sigxcpu.org>
+Date: Wed, 28 Dec 2016 19:21:49 +0100
+Subject: security-CVE-2016-2125: Don't pass GSS_C_DELEG_FLAG by default
+
+This is a backport of upstream commits
+
+   b1a056f77e793efc45df34ab7bf78fbec1bf8a59
+   b83897ae49fdee1fda73c10c7fe73362bfaba690 (code not used in wheezy)
+   3106964a640ddf6a3c08c634ff586a814f94dff8 (code not used in wheezy)
+---
+ source3/librpc/crypto/gse.c         | 1 -
+ source3/libsmb/clifsinfo.c          | 2 +-
+ source4/auth/gensec/gensec_gssapi.c | 2 +-
+ source4/scripting/bin/nsupdate-gss  | 2 +-
+ 4 files changed, 3 insertions(+), 4 deletions(-)
+
+--- a/source3/librpc/crypto/gse.c
++++ b/source3/librpc/crypto/gse.c
+@@ -162,7 +162,6 @@ static NTSTATUS gse_context_init(TALLOC_
+ 	memcpy(&gse_ctx->gss_mech, gss_mech_krb5, sizeof(gss_OID_desc));
+ 
+ 	gse_ctx->gss_c_flags = GSS_C_MUTUAL_FLAG |
+-				GSS_C_DELEG_FLAG |
+ 				GSS_C_DELEG_POLICY_FLAG |
+ 				GSS_C_REPLAY_FLAG |
+ 				GSS_C_SEQUENCE_FLAG;
+--- a/source3/libsmb/clifsinfo.c
++++ b/source3/libsmb/clifsinfo.c
+@@ -726,7 +726,7 @@ static NTSTATUS make_cli_gss_blob(TALLOC
+ 				&es->s.gss_state->gss_ctx,
+ 				srv_name,
+ 				GSS_C_NO_OID, /* default OID. */
+-				GSS_C_MUTUAL_FLAG | GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG | GSS_C_DELEG_FLAG,
++				GSS_C_MUTUAL_FLAG | GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG | GSS_C_DELEG_POLICY_FLAG,
+ 				GSS_C_INDEFINITE,	/* requested ticket lifetime. */
+ 				NULL,   /* no channel bindings */
+ 				p_tok_in,
+--- a/source4/auth/gensec/gensec_gssapi.c
++++ b/source4/auth/gensec/gensec_gssapi.c
+@@ -172,7 +172,7 @@ static NTSTATUS gensec_gssapi_start(stru
+ 	if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "mutual", true)) {
+ 		gensec_gssapi_state->want_flags |= GSS_C_MUTUAL_FLAG;
+ 	}
+-	if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation", true)) {
++	if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation", false)) {
+ 		gensec_gssapi_state->want_flags |= GSS_C_DELEG_FLAG;
+ 	}
+ 	if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "replay", true)) {
+--- a/source4/scripting/bin/nsupdate-gss
++++ b/source4/scripting/bin/nsupdate-gss
+@@ -178,7 +178,7 @@ sub negotiate_tkey($$$$)
+     my $flags = 
+ 	GSS_C_REPLAY_FLAG | GSS_C_MUTUAL_FLAG | 
+ 	GSS_C_SEQUENCE_FLAG | GSS_C_CONF_FLAG | 
+-	GSS_C_INTEG_FLAG | GSS_C_DELEG_FLAG;
++	GSS_C_INTEG_FLAG;
+ 
+ 
+     $status = GSSAPI::Cred::acquire_cred(undef, 120, undef, GSS_C_INITIATE,

package/network/services/samba36/patches/031-CVE-2017-12163-v3.6.patch

@@ -0,0 +1,136 @@
+From: =?utf-8?q?Guido_G=C3=BCnther?= <agx@sigxcpu.org>
+Date: Wed, 20 Sep 2017 20:02:03 +0200
+Subject: CVE-2017-12163: s3:smbd: Prevent client short SMB1 write from
+ writing server memory to file.
+
+BUG: https://bugzilla.samba.org/show_bug.cgi?id=13020
+
+Author: Jeremy Allison <jra@samba.org>
+Signed-off-by: Jeremy Allison <jra@samba.org>
+Signed-off-by: Stefan Metzmacher <metze@samba.org>
+---
+ source3/smbd/reply.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 50 insertions(+)
+
+--- a/source3/smbd/reply.c
++++ b/source3/smbd/reply.c
+@@ -3979,6 +3979,9 @@ void reply_writebraw(struct smb_request
+ 	}
+ 
+ 	/* Ensure we don't write bytes past the end of this packet. */
++	/*
++	 * This already protects us against CVE-2017-12163.
++	 */
+ 	if (data + numtowrite > smb_base(req->inbuf) + smb_len(req->inbuf)) {
+ 		reply_nterror(req, NT_STATUS_INVALID_PARAMETER);
+ 		error_to_writebrawerr(req);
+@@ -4080,6 +4083,11 @@ void reply_writebraw(struct smb_request
+ 			exit_server_cleanly("secondary writebraw failed");
+ 		}
+ 
++		/*
++		 * We are not vulnerable to CVE-2017-12163
++		 * here as we are guarenteed to have numtowrite
++		 * bytes available - we just read from the client.
++		 */
+ 		nwritten = write_file(req,fsp,buf+4,startpos+nwritten,numtowrite);
+ 		if (nwritten == -1) {
+ 			TALLOC_FREE(buf);
+@@ -4161,6 +4169,7 @@ void reply_writeunlock(struct smb_reques
+ 	connection_struct *conn = req->conn;
+ 	ssize_t nwritten = -1;
+ 	size_t numtowrite;
++	size_t remaining;
+ 	SMB_OFF_T startpos;
+ 	const char *data;
+ 	NTSTATUS status = NT_STATUS_OK;
+@@ -4193,6 +4202,17 @@ void reply_writeunlock(struct smb_reques
+ 	startpos = IVAL_TO_SMB_OFF_T(req->vwv+2, 0);
+ 	data = (const char *)req->buf + 3;
+ 
++	/*
++	 * Ensure client isn't asking us to write more than
++	 * they sent. CVE-2017-12163.
++	 */
++	remaining = smbreq_bufrem(req, data);
++	if (numtowrite > remaining) {
++		reply_nterror(req, NT_STATUS_INVALID_PARAMETER);
++		END_PROFILE(SMBwriteunlock);
++		return;
++	}
++
+ 	if (!fsp->print_file && numtowrite > 0) {
+ 		init_strict_lock_struct(fsp, (uint64_t)req->smbpid,
+ 		    (uint64_t)startpos, (uint64_t)numtowrite, WRITE_LOCK,
+@@ -4274,6 +4294,7 @@ void reply_write(struct smb_request *req
+ {
+ 	connection_struct *conn = req->conn;
+ 	size_t numtowrite;
++	size_t remaining;
+ 	ssize_t nwritten = -1;
+ 	SMB_OFF_T startpos;
+ 	const char *data;
+@@ -4314,6 +4335,17 @@ void reply_write(struct smb_request *req
+ 	startpos = IVAL_TO_SMB_OFF_T(req->vwv+2, 0);
+ 	data = (const char *)req->buf + 3;
+ 
++	/*
++	 * Ensure client isn't asking us to write more than
++	 * they sent. CVE-2017-12163.
++	 */
++	remaining = smbreq_bufrem(req, data);
++	if (numtowrite > remaining) {
++		reply_nterror(req, NT_STATUS_INVALID_PARAMETER);
++		END_PROFILE(SMBwrite);
++		return;
++	}
++
+ 	if (!fsp->print_file) {
+ 		init_strict_lock_struct(fsp, (uint64_t)req->smbpid,
+ 			(uint64_t)startpos, (uint64_t)numtowrite, WRITE_LOCK,
+@@ -4525,6 +4557,9 @@ void reply_write_and_X(struct smb_reques
+ 			return;
+ 		}
+ 	} else {
++		/*
++		 * This already protects us against CVE-2017-12163.
++		 */
+ 		if (smb_doff > smblen || smb_doff + numtowrite < numtowrite ||
+ 				smb_doff + numtowrite > smblen) {
+ 			reply_nterror(req, NT_STATUS_INVALID_PARAMETER);
+@@ -4894,6 +4929,7 @@ void reply_writeclose(struct smb_request
+ {
+ 	connection_struct *conn = req->conn;
+ 	size_t numtowrite;
++	size_t remaining;
+ 	ssize_t nwritten = -1;
+ 	NTSTATUS close_status = NT_STATUS_OK;
+ 	SMB_OFF_T startpos;
+@@ -4927,6 +4963,17 @@ void reply_writeclose(struct smb_request
+ 	mtime = convert_time_t_to_timespec(srv_make_unix_date3(req->vwv+4));
+ 	data = (const char *)req->buf + 1;
+ 
++	/*
++	 * Ensure client isn't asking us to write more than
++	 * they sent. CVE-2017-12163.
++	 */
++	remaining = smbreq_bufrem(req, data);
++	if (numtowrite > remaining) {
++		reply_nterror(req, NT_STATUS_INVALID_PARAMETER);
++		END_PROFILE(SMBwriteclose);
++		return;
++	}
++
+ 	if (!fsp->print_file) {
+ 		init_strict_lock_struct(fsp, (uint64_t)req->smbpid,
+ 		    (uint64_t)startpos, (uint64_t)numtowrite, WRITE_LOCK,
+@@ -5497,6 +5544,9 @@ void reply_printwrite(struct smb_request
+ 
+ 	numtowrite = SVAL(req->buf, 1);
+ 
++	/*
++	 * This already protects us against CVE-2017-12163.
++	 */
+ 	if (req->buflen < numtowrite + 3) {
+ 		reply_nterror(req, NT_STATUS_INVALID_PARAMETER);
+ 		END_PROFILE(SMBsplwr);

package/network/services/samba36/patches/032-CVE-2017-12150-v3.6.patch

@@ -0,0 +1,75 @@
+From: =?utf-8?q?Guido_G=C3=BCnther?= <agx@sigxcpu.org>
+Date: Wed, 20 Sep 2017 20:01:34 +0200
+Subject: CVE-2017-12150
+
+These are the three upstream patches
+
+  From: Stefan Metzmacher <metze@samba.org>
+  Subject: CVE-2017-12150: s3:lib: get_cmdline_auth_info_signing_state use Required for smb_encrypt
+
+  This is an addition to the fixes for CVE-2015-5296.
+
+  It applies to smb2mount -e, smbcacls -e and smbcquotas -e.
+
+  BUG: https://bugzilla.samba.org/show_bug.cgi?id=12997
+
+
+  From: Stefan Metzmacher <metze@samba.org>
+  Subject: CVE-2017-12150: libgpo: make use of Required for SMB signing in gpo_connect_server()
+
+  It's important that we use a signed connection to get the GPOs!
+
+  BUG: https://bugzilla.samba.org/show_bug.cgi?id=12997
+
+  Signed-off-by: Stefan Metzmacher <metze@samba.org>
+  Backported-by: Andreas Schneider <asn@samba.org>
+
+
+  From: Stefan Metzmacher <metze@samba.org>
+  Subject: CVE-2017-12150: s3:libsmb: only fallback to anonymous if authentication was not requested
+
+  With forced encryption or required signing we should also don't fallback.
+
+  BUG: https://bugzilla.samba.org/show_bug.cgi?id=12997
+
+---
+ libgpo/gpo_fetch.c         | 2 +-
+ source3/lib/util_cmdline.c | 3 +++
+ source3/libsmb/clidfs.c    | 2 ++
+ 3 files changed, 6 insertions(+), 1 deletion(-)
+
+--- a/libgpo/gpo_fetch.c
++++ b/libgpo/gpo_fetch.c
+@@ -151,7 +151,7 @@ static NTSTATUS gpo_connect_server(ADS_S
+ 			ads->auth.password,
+ 			CLI_FULL_CONNECTION_USE_KERBEROS |
+ 			CLI_FULL_CONNECTION_FALLBACK_AFTER_KERBEROS,
+-			Undefined);
++			Required);
+ 	if (!NT_STATUS_IS_OK(result)) {
+ 		DEBUG(10,("check_refresh_gpo: "
+ 				"failed to connect: %s\n",
+--- a/source3/lib/util_cmdline.c
++++ b/source3/lib/util_cmdline.c
+@@ -122,6 +122,9 @@ bool set_cmdline_auth_info_signing_state
+ 
+ int get_cmdline_auth_info_signing_state(const struct user_auth_info *auth_info)
+ {
++	if (auth_info->smb_encrypt) {
++		return Required;
++	}
+ 	return auth_info->signing_state;
+ }
+ 
+--- a/source3/libsmb/clidfs.c
++++ b/source3/libsmb/clidfs.c
+@@ -202,7 +202,9 @@ static struct cli_state *do_connect(TALL
+ 		/* If a password was not supplied then
+ 		 * try again with a null username. */
+ 		if (password[0] || !username[0] ||
++			force_encrypt || client_is_signing_mandatory(c) ||
+ 			get_cmdline_auth_info_use_kerberos(auth_info) ||
++			get_cmdline_auth_info_use_ccache(auth_info) ||
+ 			!NT_STATUS_IS_OK(cli_session_setup(c, "",
+ 				    		"", 0,
+ 						"", 0,

package/network/services/samba36/patches/032-CVE-2018-1050-v3-6.patch

@@ -0,0 +1,49 @@
+From 6cc45e3452194f312e04109cfdae047eb0719c7c Mon Sep 17 00:00:00 2001
+From: Jeremy Allison <jra@samba.org>
+Date: Tue, 2 Jan 2018 15:56:03 -0800
+Subject: [PATCH] CVE-2018-1050: s3: RPC: spoolss server. Protect against null
+ pointer derefs.
+
+BUG: https://bugzilla.samba.org/show_bug.cgi?id=11343
+
+Signed-off-by: Jeremy Allison <jra@samba.org>
+---
+ source3/rpc_server/spoolss/srv_spoolss_nt.c | 13 +++++++++++++
+ 1 file changed, 13 insertions(+)
+
+--- a/source3/rpc_server/spoolss/srv_spoolss_nt.c
++++ b/source3/rpc_server/spoolss/srv_spoolss_nt.c
+@@ -176,6 +176,11 @@ static void prune_printername_cache(void
+ static const char *canon_servername(const char *servername)
+ {
+ 	const char *pservername = servername;
++
++	if (servername == NULL) {
++		return "";
++	}
++
+ 	while (*pservername == '\\') {
+ 		pservername++;
+ 	}
+@@ -2080,6 +2085,10 @@ WERROR _spoolss_DeletePrinterDriver(stru
+ 		return WERR_ACCESS_DENIED;
+ 	}
+ 
++	if (r->in.architecture == NULL || r->in.driver == NULL) {
++		return WERR_INVALID_ENVIRONMENT;
++	}
++
+ 	/* check that we have a valid driver name first */
+ 
+ 	if ((version = get_version_id(r->in.architecture)) == -1)
+@@ -2225,6 +2234,10 @@ WERROR _spoolss_DeletePrinterDriverEx(st
+ 		return WERR_ACCESS_DENIED;
+ 	}
+ 
++	if (r->in.architecture == NULL || r->in.driver == NULL) {
++		return WERR_INVALID_ENVIRONMENT;
++	}
++
+ 	/* check that we have a valid driver name first */
+ 	if (get_version_id(r->in.architecture) == -1) {
+ 		/* this is what NT returns */

package/network/services/samba36/patches/200-remove_printer_support.patch

@@ -51,7 +51,7 @@
  			d_printf(_("Usage:\n"));
 --- a/source3/smbd/reply.c
 +++ b/source3/smbd/reply.c
-@@ -5208,7 +5208,11 @@ void reply_printopen(struct smb_request
+@@ -5255,7 +5255,11 @@ void reply_printopen(struct smb_request
  		return;
  	}
  
@@ -64,7 +64,7 @@
  		reply_nterror(req, NT_STATUS_ACCESS_DENIED);
  		END_PROFILE(SMBsplopen);
  		return;
-@@ -5314,7 +5318,10 @@ void reply_printqueue(struct smb_request
+@@ -5361,7 +5365,10 @@ void reply_printqueue(struct smb_request
  	   is really quite gross and only worked when there was only
  	   one printer - I think we should now only accept it if they
  	   get it right (tridge) */