Re: [PATCH V4] ext4: check hash version and filesystem casefolded consistent

[Eric Biggers]

On Fri, May 31, 2024 at 05:06:11PM +0800, 'Lizhi Xu' via syzkaller-bugs wrote:
> When mounting the ext4 filesystem, if the hash version and casefolded are not
> consistent, exit the mounting.
> 
> Reported-by: syzbot+340581ba9dceb7e06fb3@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Lizhi Xu <lizhi.xu@xxxxxxxxxxxxx>
> ---
>  fs/ext4/super.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index c682fb927b64..0ad326504c50 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -5262,6 +5262,11 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
>  		goto failed_mount;
>  
>  	ext4_hash_info_init(sb);
> +	if (es->s_def_hash_version == DX_HASH_SIPHASH && 
> +	    !ext4_has_feature_casefold(sb)) {
> +		err = -EINVAL;
> +		goto failed_mount;
> +	}

For the third time: you need to use the correct mailing lists.
Please follow Documentation/process/submitting-patches.rst.

- Eric