Re: [PATCH v3 6/7] btrfs-progs: check: update inline extent length checking

Qu Wenruo <[email protected]> Wed, 8 Jul 2026 08:13:30 +0930
Newsgroups org.kernel.vger.linux-fscrypt,org.kernel.vger.linux-btrfs,org.kernel.vger.linux-kernel
Message-ID <[email protected]>

在 2026/7/7 23:57, Daniel Vacek 写道:
> From: Sweet Tea Dorminy <[email protected]>
> 
> As part of the encryption changes, encrypted inline file extents record
> their actual data length in ram_bytes, like compressed inline file
> extents, while the item's length records the actual size. As such,
> encrypted inline extents must be treated like compressed ones for
> inode length consistency checking.
> 
> Signed-off-by: Sweet Tea Dorminy <[email protected]>
> Signed-off-by: Daniel Vacek <[email protected]>
> ---
>   check/main.c | 31 +++++++++++++++++--------------
>   1 file changed, 17 insertions(+), 14 deletions(-)
> 
> diff --git a/check/main.c b/check/main.c
> index 9447b01e..cadcfef0 100644
> --- a/check/main.c
> +++ b/check/main.c
> @@ -1720,9 +1720,7 @@ static int process_file_extent(struct btrfs_root *root,
>   	u64 disk_bytenr = 0;
>   	u64 extent_offset = 0;
>   	u64 mask = gfs_info->sectorsize - 1;
> -	u32 max_inline_size = min_t(u32, mask,
> -				BTRFS_MAX_INLINE_DATA_SIZE(gfs_info));
> -	u8 compression;
> +	u8 compression, encryption;
>   	int extent_type;
>   	int ret;
>   
> @@ -1747,25 +1745,30 @@ static int process_file_extent(struct btrfs_root *root,
>   	fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
>   	extent_type = btrfs_file_extent_type(eb, fi);
>   	compression = btrfs_file_extent_compression(eb, fi);
> +	encryption  = btrfs_file_extent_encryption(eb, fi);
>   
>   	if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
> -		num_bytes = btrfs_file_extent_ram_bytes(eb, fi);
> -		if (num_bytes == 0)
> +		u32 max_inline_size = min_t(u32, mask,
> +					BTRFS_MAX_INLINE_DATA_SIZE(gfs_info));
> +		u64 num_disk_bytes = btrfs_file_extent_inline_item_len(eb, slot);
> +		u64 num_decoded_bytes = btrfs_file_extent_ram_bytes(eb, fi);
> +		if (num_decoded_bytes == 0)
>   			rec->errors |= I_ERR_BAD_FILE_EXTENT;
> -		if (compression) {
> -			if (btrfs_file_extent_inline_item_len(eb, slot) >
> -			    max_inline_size ||
> -			    num_bytes > gfs_info->sectorsize)
> +		if (compression || encryption) {
> +			if (encryption)
> +				max_inline_size = min_t(u32, gfs_info->sectorsize,
> +					BTRFS_MAX_INLINE_DATA_SIZE(gfs_info));

The change looks good to me now.

However I'm just curious, is it possible to limit the encrypted data 
size to sectorsize-1?

Or it is some fscrypt limit internal requiring a power-of-2 size or just 
lack of interface?

Anyway I won't object this new change.

Thanks,
Qu

> +			if (num_disk_bytes > max_inline_size ||
> +			    num_decoded_bytes > gfs_info->sectorsize)
>   				rec->errors |= I_ERR_FILE_EXTENT_TOO_LARGE;
>   		} else {
> -			if (num_bytes > max_inline_size)
> +			if (num_decoded_bytes > max_inline_size)
>   				rec->errors |= I_ERR_FILE_EXTENT_TOO_LARGE;
> -			if (btrfs_file_extent_inline_item_len(eb, slot) !=
> -			    num_bytes)
> +			if (num_disk_bytes != num_decoded_bytes)
>   				rec->errors |= I_ERR_INLINE_RAM_BYTES_WRONG;
>   		}
> -		rec->found_size += num_bytes;
> -		num_bytes = (num_bytes + mask) & ~mask;
> +		rec->found_size += num_decoded_bytes;
> +		num_bytes = (num_decoded_bytes + mask) & ~mask;
>   	} else if (extent_type == BTRFS_FILE_EXTENT_REG ||
>   		   extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
>   		num_bytes = btrfs_file_extent_num_bytes(eb, fi);