diff --git a/lib/ext2fs/fileio.c b/lib/ext2fs/fileio.c
index 1f7002cd..ae5cbf17 100644
--- a/lib/ext2fs/fileio.c
+++ b/lib/ext2fs/fileio.c
@@ -389,6 +389,18 @@ errcode_t ext2fs_file_set_size2(ext2_file_t file, ext2_off64_t size)
 	old_truncate = ((old_size + file->fs->blocksize - 1) >>
 		      EXT2_BLOCK_SIZE_BITS(file->fs->super)) + 1;
 
+	/* If we're writing a large file, set the large_file flag */
+	if (LINUX_S_ISREG(file->inode.i_mode) &&
+	    EXT2_I_SIZE(&file->inode) > 0x7FFFFFFULL &&
+	    (!EXT2_HAS_RO_COMPAT_FEATURE(file->fs->super,
+					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE) ||
+	     file->fs->super->s_rev_level == EXT2_GOOD_OLD_REV)) {
+		file->fs->super->s_feature_ro_compat |=
+				EXT2_FEATURE_RO_COMPAT_LARGE_FILE;
+		ext2fs_update_dynamic_rev(file->fs);
+		ext2fs_mark_super_dirty(file->fs);
+	}
+
 	file->inode.i_size = size & 0xffffffff;
 	file->inode.i_size_high = (size >> 32);
 	if (file->ino) {