diff --git a/samba-3.4.5-cifs_upcall.patch b/samba-3.4.5-cifs_upcall.patch
new file mode 100644
index 0000000..7cbc0e0
--- /dev/null
+++ b/samba-3.4.5-cifs_upcall.patch
@@ -0,0 +1,61 @@
+From efc2e996e3348392f1fd5c0ec7feae4f869fb8f9 Mon Sep 17 00:00:00 2001
+From: Jeff Layton <jlayton@redhat.com>
+Date: Tue, 16 Feb 2010 09:16:42 -0500
+Subject: [PATCH] cifs.upcall: allocate a talloc context for smb_krb5_unparse_name
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+cifs.upcall calls smb_krb5_unparse_name with a NULL talloc context.
+Older versions of this function though will conditionally use
+SMB_REALLOC instead of TALLOC_REALLOC when a NULL context is passed
+in. To make it more consistent, just spawn a talloc context that
+we can pass into this function.
+
+Resolves:
+https://bugzilla.redhat.com/show_bug.cgi?id=565446
+https://bugzilla.samba.org/show_bug.cgi?id=6868
+
+Reported-by: Ludek Finstrle <luf@seznam.cz>
+Signed-off-by: Jeff Layton <jlayton@redhat.com>
+Signed-off-by: Günther Deschner <gd@samba.org>
+(cherry picked from commit a8cc2fa09ed43a167f62711bef363a5ac335dc78)
+---
+ source3/client/cifs.upcall.c |    5 ++++-
+ 1 files changed, 4 insertions(+), 1 deletions(-)
+
+diff --git a/source3/client/cifs.upcall.c b/source3/client/cifs.upcall.c
+index 1617e0e..d573e76 100644
+--- a/source3/client/cifs.upcall.c
++++ b/source3/client/cifs.upcall.c
+@@ -55,6 +55,7 @@ get_tgt_time(const char *ccname) {
+ 	krb5_principal principal;
+ 	time_t credtime = 0;
+ 	char *realm = NULL;
++	TALLOC_CTX *mem_ctx;
+ 
+ 	if (krb5_init_context(&context)) {
+ 		syslog(LOG_DEBUG, "%s: unable to init krb5 context", __func__);
+@@ -86,9 +87,10 @@ get_tgt_time(const char *ccname) {
+ 		goto err_ccstart;
+ 	}
+ 
++	mem_ctx = talloc_init("cifs.upcall");
+ 	while (!credtime && !krb5_cc_next_cred(context, ccache, &cur, &creds)) {
+ 		char *name;
+-		if (smb_krb5_unparse_name(NULL, context, creds.server, &name)) {
++		if (smb_krb5_unparse_name(mem_ctx, context, creds.server, &name)) {
+ 			syslog(LOG_DEBUG, "%s: unable to unparse name", __func__);
+ 			goto err_endseq;
+ 		}
+@@ -101,6 +103,7 @@ get_tgt_time(const char *ccname) {
+ 		TALLOC_FREE(name);
+         }
+ err_endseq:
++	TALLOC_FREE(mem_ctx);
+         krb5_cc_end_seq_get(context, ccache, &cur);
+ err_ccstart:
+ 	krb5_free_principal(context, principal);
+-- 
+1.6.6
+
diff --git a/samba.spec b/samba.spec
index e367bec..0884ef8 100644
--- a/samba.spec
+++ b/samba.spec
@@ -1,4 +1,4 @@
-%define main_release 55
+%define main_release 56
 %define samba_version 3.4.5
 %define tdb_version 1.1.3
 %define talloc_version 1.3.0
@@ -47,6 +47,7 @@ Patch107: samba-3.2.0pre1-grouppwd.patch
 Patch200: samba-3.2.5-inotify.patch
 Patch201: samba-3.4.5-pdbedit.patch
 Patch202: samba-3.4.5-CVE-2009-3297-mount_cifs.patch
+Patch203: samba-3.4.5-cifs_upcall.patch
 
 Requires(pre): samba-common = %{epoch}:%{samba_version}-%{release}
 Requires: pam >= 0:0.64
@@ -206,6 +207,7 @@ cp %{SOURCE11} packaging/Fedora/
 %patch200 -p0 -b .inotify
 %patch201 -p1 -b .pdbedit
 %patch202 -p1 -b .CVE-2009-3297-mount_cifs
+%patch203 -p1 -b .cifs_upcall
 
 mv %samba_source/VERSION %samba_source/VERSION.orig
 sed -e 's/SAMBA_VERSION_VENDOR_SUFFIX=$/&\"%{samba_release}\"/' < %samba_source/VERSION.orig > %samba_source/VERSION
@@ -658,6 +660,10 @@ exit 0
 %{_datadir}/pixmaps/samba/logo-small.png
 
 %changelog
+* Wed Feb 17 2010 Guenther Deschner <gdeschner@redhat.com> - 3.4.5-56
+- Fix crash in cifs.upcall
+- resolves: #565446
+
 * Wed Jan 26 2010 Guenther Deschner <gdeschner@redhat.com> - 3.4.5-55
 - Security Release, fixes CVE-2009-3297
 - resolves: #532940