1 files changed, 23 insertions, 2 deletions
diff --git a/tests/qemu-iotests/308 b/tests/qemu-iotests/308
index 2e3f8f4282..bde4aac2fa 100755
--- a/tests/qemu-iotests/308
+++ b/tests/qemu-iotests/308
@@ -230,8 +230,29 @@ echo '=== Writable export ==='
 fuse_export_add 'export-mp' "'mountpoint': '$EXT_MP', 'writable': true"
 
 # Check that writing to the read-only export fails
-$QEMU_IO -f raw -c 'write -P 42 1M 64k' "$TEST_IMG" 2>&1 \
-    | _filter_qemu_io | _filter_testdir | _filter_imgfmt
+output=$($QEMU_IO -f raw -c 'write -P 42 1M 64k' "$TEST_IMG" 2>&1 \
+             | _filter_qemu_io | _filter_testdir | _filter_imgfmt)
+
+# Expected reference output: Opening the file fails because it has no
+# write permission
+reference="Could not open 'TEST_DIR/t.IMGFMT': Permission denied"
+
+if echo "$output" | grep -q "$reference"; then
+    echo "Writing to read-only export failed: OK"
+elif echo "$output" | grep -q "write failed: Permission denied"; then
+    # With CAP_DAC_OVERRIDE (e.g. when running this test as root), the export
+    # can be opened regardless of its file permissions, but writing will then
+    # fail.  This is not the result for which we want to test, so count this as
+    # a SKIP.
+    _casenotrun "Opening RO export as R/W succeeded, perhaps because of" \
+        "CAP_DAC_OVERRIDE"
+
+    # Still, write this to the reference output to make the test pass
+    echo "Writing to read-only export failed: OK"
+else
+    echo "Writing to read-only export failed: ERROR"
+    echo "$output"
+fi
 
 # But here it should work
 $QEMU_IO -f raw -c 'write -P 42 1M 64k' "$EXT_MP" | _filter_qemu_io