diff --git a/nbdkit.spec b/nbdkit.spec
index 8569d36..448b003 100644
--- a/nbdkit.spec
+++ b/nbdkit.spec
@@ -45,8 +45,8 @@ ExclusiveArch:  x86_64
 %global source_directory 1.23-development
 
 Name:           nbdkit
-Version:        1.23.10
-Release:        2%{?dist}
+Version:        1.23.12
+Release:        1%{?dist}
 Summary:        NBD server
 
 License:        BSD
@@ -578,6 +578,7 @@ Requires:       %{name}-server%{?_isa} = %{version}-%{release}
 Provides:       %{name}-blocksize-filter = %{version}-%{release}
 Provides:       %{name}-cache-filter = %{version}-%{release}
 Provides:       %{name}-cacheextents-filter = %{version}-%{release}
+Provides:       %{name}-checkwrite-filter = %{version}-%{release}
 Provides:       %{name}-cow-filter = %{version}-%{release}
 Provides:       %{name}-ddrescue-filter = %{version}-%{release}
 Provides:       %{name}-delay-filter = %{version}-%{release}
@@ -618,6 +619,8 @@ nbdkit-cache-filter        Server-side cache.
 
 nbdkit-cacheextents-filter Cache extents.
 
+nbdkit-checkwrite-filter   Check writes match contents of plugin.
+
 nbdkit-cow-filter          Copy-on-write overlay for read-only plugins.
 
 nbdkit-ddrescue-filter     Filter for serving from ddrescue dump.
@@ -1130,6 +1133,7 @@ export LIBGUESTFS_TRACE=1
 %{_libdir}/%{name}/filters/nbdkit-blocksize-filter.so
 %{_libdir}/%{name}/filters/nbdkit-cache-filter.so
 %{_libdir}/%{name}/filters/nbdkit-cacheextents-filter.so
+%{_libdir}/%{name}/filters/nbdkit-checkwrite-filter.so
 %{_libdir}/%{name}/filters/nbdkit-cow-filter.so
 %{_libdir}/%{name}/filters/nbdkit-ddrescue-filter.so
 %{_libdir}/%{name}/filters/nbdkit-delay-filter.so
@@ -1160,6 +1164,7 @@ export LIBGUESTFS_TRACE=1
 %{_mandir}/man1/nbdkit-blocksize-filter.1*
 %{_mandir}/man1/nbdkit-cache-filter.1*
 %{_mandir}/man1/nbdkit-cacheextents-filter.1*
+%{_mandir}/man1/nbdkit-checkwrite-filter.1*
 %{_mandir}/man1/nbdkit-cow-filter.1*
 %{_mandir}/man1/nbdkit-ddrescue-filter.1*
 %{_mandir}/man1/nbdkit-delay-filter.1*
@@ -1260,6 +1265,13 @@ export LIBGUESTFS_TRACE=1
 
 
 %changelog
+* Tue Dec 29 2020 Richard W.M. Jones <rjones@redhat.com> - 1.23.12-1
+- New upstream development version 1.23.12.
+
+* Tue Dec 22 2020 Richard W.M. Jones <rjones@redhat.com> - 1.23.11-1
+- New upstream development version 1.23.11.
+- New nbdkit-checkwrite-filter.
+
 * Thu Dec 10 2020 Richard W.M. Jones <rjones@redhat.com> - 1.23.10-2
 - Avoid boto3 dependency on RHEL.
 
diff --git a/sources b/sources
index 7120420..5c1815c 100644
--- a/sources
+++ b/sources
@@ -1,2 +1,2 @@
-SHA512 (nbdkit-1.23.10.tar.gz) = b1121dda040084e09a09af44415452f83eba1ed85f4f57c3c7386621872bc5c3914f1eb08b9f7592bff1533ae16a190f45a432a53215ea49e000f68abfd9b954
-SHA512 (nbdkit-1.23.10.tar.gz.sig) = cb252fc2058fa856672e890a233f36da71e1fe4eac4e38c83b2837ec79efb3379e8b161e7f89067c75462bcfae9a7fb1521b48eff8dfeacb9f69676171e6293a
+SHA512 (nbdkit-1.23.12.tar.gz) = 7080ed8571c408a8a680f7cd095054f7d2eb770400489149be9659bf8bece59b6efc65e9a6062a14c48227c9c02ad490fc4122a0ead6adfac51bb2d9727e01f2
+SHA512 (nbdkit-1.23.12.tar.gz.sig) = 0a4841e14d7ba62b3d34f2d7d258d92b6bfd47992974d048af4a7e91366d7d167fa2ad554f1a396066291861d37a1850b976f845cb89ac0582f1d1c15565bacc