On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks. This may
caused the superblock being corrupted with zero blocks count.
Fixes: 1c6bd7173d66
Signed-off-by: Jerry Lee <jerrylee@qnap.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 3.7+
n_desc_blocks = o_desc_blocks +
le16_to_cpu(es->s_reserved_gdt_blocks);
n_group = n_desc_blocks * EXT4_DESC_PER_BLOCK(sb);
- n_blocks_count = n_group * EXT4_BLOCKS_PER_GROUP(sb);
+ n_blocks_count = (ext4_fsblk_t)n_group *
+ EXT4_BLOCKS_PER_GROUP(sb);
n_group--; /* set to last group number */
}