Re: [PATCH v1] erofs-utils: mkfs: fix fingerprint not set in certain modes

[Gao Xiang <hsiangkao@linux.alibaba.com>]

Hi Yuezhang,

On 2026/4/10 14:05, Yuezhang Mo wrote:
> In certain modes, such as "--tar=f --sort=none", data is written to
> the image before fingerprint calculation. In this case, ->datasource
> will be set to `EROFS_INODE_DATA_SOURCE_NONE`.
> 
> The original `erofs_set_inode_fingerprint()` function only attempts to
> read data from a local file or disk buffer; it cannot handle the
> `EROFS_INODE_DATA_SOURCE_NONE` case, causing fingerprint setting to be
> skipped.
> 
> This patch adds handling for the `EROFS_INODE_DATA_SOURCE_NONE` case,
> reading data from the image and calculating the fingerprint.
> 
> Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
> Reviewed-by: Friendy Su <friendy.su@sony.com>
> Reviewed-by: Daniel Palmer <daniel.palmer@sony.com>
> ---
>   lib/inode.c | 20 ++++++++++++++------
>   1 file changed, 14 insertions(+), 6 deletions(-)
> 
> diff --git a/lib/inode.c b/lib/inode.c
> index 2cfc6c5..51d5266 100644
> --- a/lib/inode.c
> +++ b/lib/inode.c
> @@ -1975,6 +1975,13 @@ static int erofs_set_inode_fingerprint(struct erofs_inode *inode, int fd,
>   
>   	if (!ishare_xattr_prefix_id)
>   		return 0;
> +
> +	if (inode->datasource == EROFS_INODE_DATA_SOURCE_NONE) {
> +		ret = erofs_iopen(&vf, inode);
> +		if (ret)
> +			return ret;
> +	}
> +
>   	erofs_sha256_init(&md);
>   	do {
>   		u8 buf[32768];
> @@ -2018,12 +2025,6 @@ static int erofs_mkfs_begin_nondirectory(const struct erofs_mkfs_btctx *btctx,
>   			goto out;
>   		}
>   
> -		if (S_ISREG(inode->i_mode) && inode->i_size) {
> -			ret = erofs_set_inode_fingerprint(inode, ctx.fd, ctx.fpos);
> -			if (ret < 0)
> -				return ret;
> -		}

I vaguely remembered we have to leave it here since
otherwise it may impact compressed files.

Also EROFS_INODE_DATA_SOURCE_NONE means that mkfs
dump will change nothing about that, so I suggest

apply erofs_set_inode_fingerprint() to every
EROFS_INODE_DATA_SOURCE_NONE user
(e.g. in lib/tar.c) instead.

Thanks,
Gao Xiang