diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 5664ee6..13c49af7 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3416,6 +3416,13 @@
 		goto failed_mount;
 	}
 
+	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
+		ext4_msg(sb, KERN_ERR,
+			 "Number of reserved GDT blocks insanely large: %d",
+			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
+		goto failed_mount;
+	}
+
 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
 		err = bdev_dax_supported(sb, blocksize);
 		if (err)