ITS#7256 Add some necessary checks.

servers/slapd/slapmodify.c

@@ -282,7 +282,8 @@ slapmodify( int argc, char **argv )
 			e = e_tmp;
 		}
 
-		for ( n = 0; lr.lrop_mods[ n ] != NULL; n++ ) {
+		if ( lr.lrop_mods ) {
+			for ( n = 0; lr.lrop_mods && lr.lrop_mods[ n ] != NULL; n++ ) {
 				LDAPMod *mod = lr.lrop_mods[ n ];
 				Modification mods = { 0 };
 				unsigned i = 0;
@@ -327,12 +328,15 @@ slapmodify( int argc, char **argv )
 						;
 				}
 
+				if ( i != 0 )
+				{
 					mods.sm_values = SLAP_CALLOC( sizeof( struct berval ), i + 1 );
 					if ( normalize ) {
 						mods.sm_nvalues = SLAP_CALLOC( sizeof( struct berval ), i + 1 );
 					} else {
 						mods.sm_nvalues = NULL;
 					}
+				}
 				mods.sm_numvals = i;
 
 				for ( i = 0; i < mods.sm_numvals; i++ ) {
@@ -449,6 +453,7 @@ slapmodify( int argc, char **argv )
 				entry_free( e );
 				break;
 			}
+		}
 
 		if ( SLAP_LASTMOD(be) ) {
 			time_t now = slap_get_time();