diff --git a/t/t9011-svn-da.sh b/t/t9011-svn-da.sh
index ba8ce052aa..72691b9379 100755
--- a/t/t9011-svn-da.sh
+++ b/t/t9011-svn-da.sh
@@ -121,11 +121,10 @@ test_expect_success 'preimage view: reject truncated preimage' '
 	test_must_fail test-svn-fe -d preimage clear.longread 9
 '
 
-test_expect_success 'inline data' '
+test_expect_success 'forbid unconsumed inline data' '
 	printf "SVNQ%b%s%b%s" "QQQQ\003" "bar" "QQQQ\001" "x" |
 		q_to_nul >inline.clear &&
-	test-svn-fe -d preimage inline.clear 18 >actual &&
-	test_cmp empty actual
+	test_must_fail test-svn-fe -d preimage inline.clear 18 >actual
 '
 
 test_expect_success 'reject truncated inline data' '
diff --git a/vcs-svn/svndiff.c b/vcs-svn/svndiff.c
index ed1d4a08be..fb7dc22f92 100644
--- a/vcs-svn/svndiff.c
+++ b/vcs-svn/svndiff.c
@@ -208,6 +208,8 @@ static int apply_window_in_core(struct window *ctx)
 	     )
 		if (execute_one_instruction(ctx, &instructions, &data_pos))
 			return -1;
+	if (data_pos != ctx->data.len)
+		return error("invalid delta: does not copy all inline data");
 	return 0;
 }