diff --git a/tests/qemu-iotests/026 b/tests/qemu-iotests/026
index 3430029ed6..d89729697f 100755
--- a/tests/qemu-iotests/026
+++ b/tests/qemu-iotests/026
@@ -215,6 +215,27 @@ _make_test_img 64M
 $QEMU_IO -c "write 0 1M" -c "write 0 1M" "$BLKDBG_TEST_IMG" | _filter_qemu_io
 _check_test_img
 
+echo
+echo === Avoid freeing preallocated zero clusters on failure ===
+echo
+
+cat > "$TEST_DIR/blkdebug.conf" <<EOF
+[inject-error]
+event = "write_aio"
+errno = "5"
+once = "on"
+EOF
+
+_make_test_img $CLUSTER_SIZE
+# Create a preallocated zero cluster
+$QEMU_IO -c "write 0 $CLUSTER_SIZE" -c "write -z 0 $CLUSTER_SIZE" "$TEST_IMG" \
+    | _filter_qemu_io
+# Try to overwrite it (prompting an I/O error from blkdebug), thus
+# triggering the alloc abort code
+$QEMU_IO -c "write 0 $CLUSTER_SIZE" "$BLKDBG_TEST_IMG" | _filter_qemu_io
+
+_check_test_img
+
 # success, all done
 echo "*** done"
 rm -f $seq.full
diff --git a/tests/qemu-iotests/026.out b/tests/qemu-iotests/026.out
index ff0817b6f2..83989996ff 100644
--- a/tests/qemu-iotests/026.out
+++ b/tests/qemu-iotests/026.out
@@ -643,4 +643,14 @@ write failed: Input/output error
 wrote 1048576/1048576 bytes at offset 0
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 No errors were found on the image.
+
+=== Avoid freeing preallocated zero clusters on failure ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1024
+wrote 1024/1024 bytes at offset 0
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 1024/1024 bytes at offset 0
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+write failed: Input/output error
+No errors were found on the image.
 *** done
diff --git a/tests/qemu-iotests/026.out.nocache b/tests/qemu-iotests/026.out.nocache
index 495d013007..9359d26d7e 100644
--- a/tests/qemu-iotests/026.out.nocache
+++ b/tests/qemu-iotests/026.out.nocache
@@ -651,4 +651,14 @@ write failed: Input/output error
 wrote 1048576/1048576 bytes at offset 0
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 No errors were found on the image.
+
+=== Avoid freeing preallocated zero clusters on failure ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1024
+wrote 1024/1024 bytes at offset 0
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 1024/1024 bytes at offset 0
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+write failed: Input/output error
+No errors were found on the image.
 *** done