2 files changed, 10 insertions, 0 deletions

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index 0b8105b3293d..799a92bdf577 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -208,6 +208,9 @@ static int ext4_init_block_bitmap(struct super_block *sb,
         memset(bh->b_data, 0, sb->s_blocksize);
 
         bit_max = ext4_num_base_meta_clusters(sb, block_group);
+        if ((bit_max >> 3) >= bh->b_size)
+                return -EFSCORRUPTED;
+
         for (bit = 0; bit < bit_max; bit++)
                 ext4_set_bit(bit, bh->b_data);
 
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 5664ee66b301..13c49af7a06a 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3416,6 +3416,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                 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)