Re: [PATCH 7/7] ext4: set the type of max_zeroout to unsigned int to avoid overflow

Zhang Yi
2024-01-27T02:12:10Z

On 2024/1/26 16:57, Baokun Li wrote:
> The max_zeroout is of type int and the s_extent_max_zeroout_kb is of
> type uint, and the s_extent_max_zeroout_kb can be freely modified via
> the sysfs interface. When the block size is 1024, max_zeroout may
> overflow, so declare it as unsigned int to avoid overflow.
>
> Signed-off-by: Baokun Li <libaokun1@huawei.com>

Looks good to me.

Reviewed-by: Zhang Yi <yi.zhang@huawei.com>

> ---
> fs/ext4/extents.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
> index 01299b55a567..8653b13e8248 100644
> --- a/fs/ext4/extents.c
> +++ b/fs/ext4/extents.c
> @@ -3425,10 +3425,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
> struct ext4_extent zero_ex1, zero_ex2;
> struct ext4_extent *ex, *abut_ex;
> ext4_lblk_t ee_block, eof_block;
> - unsigned int ee_len, depth, map_len = map->m_len;
> - int allocated = 0, max_zeroout = 0;
> - int err = 0;
> - int split_flag = EXT4_EXT_DATA_VALID2;
> + unsigned int ee_len, depth, map_len = map->m_len, max_zeroout = 0;
> + int err = 0, allocated = 0, split_flag = EXT4_EXT_DATA_VALID2;
>
> ext_debug(inode, "logical block %llu, max_blocks %u\n",
> (unsigned long long)map->m_lblk, map_len);
>