diff --git a/fs/incfs/vfs.c b/fs/incfs/vfs.c
index c6f21b1cd501..da6524b1aa93 100644
--- a/fs/incfs/vfs.c
+++ b/fs/incfs/vfs.c
@@ -648,6 +648,7 @@ static void notify_unlink(struct dentry *dentry, const char *file_id_str,
 static void maybe_delete_incomplete_file(struct file *f,
 					 struct data_file *df)
 {
+	struct backing_file_context *bfc;
 	struct mount_info *mi = df->df_mount_info;
 	char *file_id_str = NULL;
 	struct dentry *incomplete_file_dentry = NULL;
@@ -657,6 +658,22 @@ static void maybe_delete_incomplete_file(struct file *f,
 	if (atomic_read(&df->df_data_blocks_written) < df->df_data_block_count)
 		goto out;
 
+	/* Truncate file to remove any preallocated space */
+	bfc = df->df_backing_file_context;
+	if (bfc) {
+		struct file *f = bfc->bc_file;
+
+		if (f) {
+			loff_t size = i_size_read(file_inode(f));
+
+			error = vfs_truncate(&f->f_path, size);
+			if (error)
+				/* No useful action on failure */
+				pr_warn("incfs: Failed to truncate complete file: %d\n",
+					error);
+		}
+	}
+
 	/* This is best effort - there is no useful action to take on failure */
 	file_id_str = file_id_to_str(df->df_id);
 	if (!file_id_str)
diff --git a/tools/testing/selftests/filesystems/incfs/incfs_test.c b/tools/testing/selftests/filesystems/incfs/incfs_test.c
index 6e036e10215e..d48b65ea9aae 100644
--- a/tools/testing/selftests/filesystems/incfs/incfs_test.c
+++ b/tools/testing/selftests/filesystems/incfs/incfs_test.c
@@ -2,6 +2,8 @@
 /*
  * Copyright 2018 Google LLC
  */
+#define _GNU_SOURCE
+
 #include <alloca.h>
 #include <dirent.h>
 #include <errno.h>
@@ -4116,6 +4118,46 @@ static int mmap_test(const char *mount_dir)
 	return result;
 }
 
+static int truncate_test(const char *mount_dir)
+{
+	int result = TEST_FAILURE;
+	char *backing_dir = NULL;
+	int cmd_fd = -1;
+	struct test_file file = {
+		  .name = "file",
+		  .size = INCFS_DATA_FILE_BLOCK_SIZE,
+	};
+	char *backing_file = NULL;
+	int fd = -1;
+	struct stat st;
+
+	TEST(backing_dir = create_backing_dir(mount_dir), backing_dir);
+	TESTEQUAL(mount_fs(mount_dir, backing_dir, 0), 0);
+	TEST(cmd_fd = open_commands_file(mount_dir), cmd_fd != -1);
+	TESTEQUAL(emit_file(cmd_fd, NULL, file.name, &file.id, file.size, NULL),
+		  0);
+	TEST(backing_file = concat_file_name(backing_dir, file.name),
+	     backing_file);
+	TEST(fd = open(backing_file, O_RDWR | O_CLOEXEC), fd != -1);
+	TESTEQUAL(stat(backing_file, &st), 0);
+	TESTCOND(st.st_blocks < 128);
+	TESTEQUAL(fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 1 << 24), 0);
+	TESTEQUAL(stat(backing_file, &st), 0);
+	TESTCOND(st.st_blocks > 32768);
+	TESTEQUAL(emit_test_file_data(mount_dir, &file), 0);
+	TESTEQUAL(stat(backing_file, &st), 0);
+	TESTCOND(st.st_blocks < 128);
+
+	result = TEST_SUCCESS;
+out:
+	close(fd);
+	free(backing_file);
+	close(cmd_fd);
+	umount(mount_dir);
+	free(backing_dir);
+	return result;
+}
+
 static char *setup_mount_dir()
 {
 	struct stat st;
@@ -4233,6 +4275,7 @@ int main(int argc, char *argv[])
 		MAKE_TEST(verity_test),
 		MAKE_TEST(enable_verity_test),
 		MAKE_TEST(mmap_test),
+		MAKE_TEST(truncate_test),
 	};
 #undef MAKE_TEST