diff -Nru shadow-4.5/debian/changelog shadow-4.5/debian/changelog
--- shadow-4.5/debian/changelog	2019-03-22 19:05:38.000000000 +0000
+++ shadow-4.5/debian/changelog	2019-08-21 10:25:16.000000000 +0000
@@ -1,3 +1,10 @@
+shadow (1:4.5-1ubuntu2.1) bionic; urgency=medium
+
+  * debian/patches/1014_extrausers_delgroup.patch
+    - add --extrausers option to "groupdel" (LP: #1840375)
+
+ -- Michael Vogt <michael.vogt@ubuntu.com>  Wed, 21 Aug 2019 12:25:16 +0200
+
 shadow (1:4.5-1ubuntu2) bionic; urgency=medium
 
   * debian/patches/1013_extrausers_deluser.patch
diff -Nru shadow-4.5/debian/patches/1014_extrausers_delgroup.patch shadow-4.5/debian/patches/1014_extrausers_delgroup.patch
--- shadow-4.5/debian/patches/1014_extrausers_delgroup.patch	1970-01-01 00:00:00.000000000 +0000
+++ shadow-4.5/debian/patches/1014_extrausers_delgroup.patch	2019-08-21 10:24:23.000000000 +0000
@@ -0,0 +1,62 @@
+Index: shadow-4.5/src/groupdel.c
+===================================================================
+--- shadow-4.5.orig/src/groupdel.c
++++ shadow-4.5/src/groupdel.c
+@@ -84,6 +84,12 @@ static void open_files (void);
+ static void group_busy (gid_t gid);
+ static void process_flags (int argc, char **argv);
+ 
++#ifndef EXTRAUSERS_OPT
++#define EXTRAUSERS_OPT 100000
++#endif
++
++static bool use_extrausers = false;
++
+ /*
+  * usage - display usage message and exit
+  */
+@@ -98,6 +104,7 @@ static /*@noreturn@*/void usage (int sta
+ 	(void) fputs (_("  -h, --help                    display this help message and exit\n"), usageout);
+ 	(void) fputs (_("  -R, --root CHROOT_DIR         directory to chroot into\n"), usageout);
+ 	(void) fputs (_("  -f, --force                   delete group even if it is the primary group of a user\n"), usageout);
++        (void) fputs (_("      --extrausers              Use the extra users database\n"), usageout);
+ 	(void) fputs ("\n", usageout);
+ 	exit (status);
+ }
+@@ -320,6 +327,7 @@ static void process_flags (int argc, cha
+ 	static struct option long_options[] = {
+ 		{"help", no_argument,       NULL, 'h'},
+ 		{"root", required_argument, NULL, 'R'},
++		{"extrausers", no_argument, NULL, EXTRAUSERS_OPT},
+ 		{NULL, 0, NULL, '\0'}
+ 	};
+ 
+@@ -334,6 +342,9 @@ static void process_flags (int argc, cha
+ 		case 'f':
+ 			check_group_busy = false;
+ 			break;
++		case EXTRAUSERS_OPT:
++			use_extrausers = true;
++			break;
+ 		default:
+ 			usage (E_USAGE);
+ 		}
+@@ -474,6 +485,18 @@ int main (int argc, char **argv)
+ 		group_busy (group_id);
+ 	}
+ 
++        if (use_extrausers) {
++               pw_setdbname (EXTRAUSERS_PASSWD_FILE);
++               spw_setdbname (EXTRAUSERS_SHADOW_FILE);
++               gr_setdbname (EXTRAUSERS_GROUP_FILE);
++               /* TODO expose this information in other tools */
++               sub_uid_setdbname(EXTRAUSERS_SUBUID_FILE);
++               sub_gid_setdbname(EXTRAUSERS_SUBGID_FILE);
++#ifdef SHADOWGRP
++               sgr_setdbname (EXTRAUSERS_SHADOWGROUP_FILE);
++#endif
++        }
++
+ 	/*
+ 	 * Do the hard stuff - open the files, delete the group entries,
+ 	 * then close and update the files.
diff -Nru shadow-4.5/debian/patches/series shadow-4.5/debian/patches/series
--- shadow-4.5/debian/patches/series	2019-03-22 19:05:38.000000000 +0000
+++ shadow-4.5/debian/patches/series	2019-08-21 10:25:04.000000000 +0000
@@ -18,4 +18,5 @@
 1011_extrausers_toggle.patch
 1012_extrausers_chfn.patch
 1013_extrausers_deluser.patch
+1014_extrausers_delgroup.patch
 2000_fix-su-pam-env-handling