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

=E5=9C=A8 2026/7/8 14:30, Daniel Vacek =E5=86=99=E9=81=93:
> On Wed, 8 Jul 2026 at 00:43, Qu Wenruo <[email protected]> wrote:
>> =E5=9C=A8 2026/7/7 23:57, Daniel Vacek =E5=86=99=E9=81=93:
>>> From: Sweet Tea Dorminy <[email protected]>
>>>
>>> As part of the encryption changes, encrypted inline file extents recor=
d
>>> 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 =3D 0;
>>>        u64 extent_offset =3D 0;
>>>        u64 mask =3D gfs_info->sectorsize - 1;
>>> -     u32 max_inline_size =3D 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_ro=
ot *root,
>>>        fi =3D btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
>>>        extent_type =3D btrfs_file_extent_type(eb, fi);
>>>        compression =3D btrfs_file_extent_compression(eb, fi);
>>> +     encryption  =3D btrfs_file_extent_encryption(eb, fi);
>>>
>>>        if (extent_type =3D=3D BTRFS_FILE_EXTENT_INLINE) {
>>> -             num_bytes =3D btrfs_file_extent_ram_bytes(eb, fi);
>>> -             if (num_bytes =3D=3D 0)
>>> +             u32 max_inline_size =3D min_t(u32, mask,
>>> +                                     BTRFS_MAX_INLINE_DATA_SIZE(gfs_i=
nfo));
>>> +             u64 num_disk_bytes =3D btrfs_file_extent_inline_item_len=
(eb, slot);
>>> +             u64 num_decoded_bytes =3D btrfs_file_extent_ram_bytes(eb=
, fi);
>>> +             if (num_decoded_bytes =3D=3D 0)
>>>                        rec->errors |=3D 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 =3D min_t(u32, gfs_info-=
>sectorsize,
>>> +                                     BTRFS_MAX_INLINE_DATA_SIZE(gfs_i=
nfo));
>>
>> 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 jus=
t
>> lack of interface?
>=20
> The encrypted data has the granularity of the cipher block size. With
> AES, it's 16 bytes. Hence why.
> Eventually the best we could do would be sectorsize-16. But then, if
> the cipher changed in the future...

Thanks a lot, that explains the reason why we can not follow the old=20
sectorsize - 1 limit.

Thanks,
Qu

>=20
> --nX
>=20
>> 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 |=3D I_ERR_FILE_EXTENT_TOO_=
LARGE;
>>>                } else {
>>> -                     if (num_bytes > max_inline_size)
>>> +                     if (num_decoded_bytes > max_inline_size)
>>>                                rec->errors |=3D I_ERR_FILE_EXTENT_TOO_=
LARGE;
>>> -                     if (btrfs_file_extent_inline_item_len(eb, slot) =
!=3D
>>> -                         num_bytes)
>>> +                     if (num_disk_bytes !=3D num_decoded_bytes)
>>>                                rec->errors |=3D I_ERR_INLINE_RAM_BYTES=
_WRONG;
>>>                }
>>> -             rec->found_size +=3D num_bytes;
>>> -             num_bytes =3D (num_bytes + mask) & ~mask;
>>> +             rec->found_size +=3D num_decoded_bytes;
>>> +             num_bytes =3D (num_decoded_bytes + mask) & ~mask;
>>>        } else if (extent_type =3D=3D BTRFS_FILE_EXTENT_REG ||
>>>                   extent_type =3D=3D BTRFS_FILE_EXTENT_PREALLOC) {
>>>                num_bytes =3D btrfs_file_extent_num_bytes(eb, fi);
>>
>=20