Ocfs2 devel - May 2023 - [PATCH] ocfs2: check new file size on fallocate call

On 5/29/23 11:26 PM, Lu?s Henriques wrote:
> When changing a file size with fallocate() the new size isn't being
> checked.  In particular, the FSIZE ulimit isn't being checked, which
makes
> fstest generic/228 fail.  Simply adding a call to inode_newsize_ok() fixes
> this issue.
> 
> Signed-off-by: Lu?s Henriques <lhenriques at suse.de>
> ---
>  fs/ocfs2/file.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index efb09de4343d..b173c36bcab3 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -2100,14 +2100,20 @@ static long ocfs2_fallocate(struct file *file, int
mode, loff_t offset,
>  	struct ocfs2_space_resv sr;
>  	int change_size = 1;
>  	int cmd = OCFS2_IOC_RESVSP64;
> +	int ret = 0;
>  
>  	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
>  		return -EOPNOTSUPP;
This means we only support keep-size and pouch_hole.
And it seems pouch_hole will also imply keep-size.
>  	if (!ocfs2_writes_unwritten_extents(osb))
>  		return -EOPNOTSUPP;
>  
> -	if (mode & FALLOC_FL_KEEP_SIZE)
> +	if (mode & FALLOC_FL_KEEP_SIZE) {
>  		change_size = 0;
> +	} else {
Seems this will be a dead branch?

Thanks,
Joseph
> +		ret = inode_newsize_ok(inode, offset + len);
> +		if (ret)
> +			return ret;
> +	}
>  
>  	if (mode & FALLOC_FL_PUNCH_HOLE)
>  		cmd = OCFS2_IOC_UNRESVSP64;

Joseph Qi <joseph.qi at linux.alibaba.com> writes:
> On 5/29/23 11:26 PM, Lu?s Henriques wrote:
>> When changing a file size with fallocate() the new size isn't being
>> checked.  In particular, the FSIZE ulimit isn't being checked,
which makes
>> fstest generic/228 fail.  Simply adding a call to inode_newsize_ok()
fixes
>> this issue.
>> 
>> Signed-off-by: Lu?s Henriques <lhenriques at suse.de>
>> ---
>>  fs/ocfs2/file.c | 8 +++++++-
>>  1 file changed, 7 insertions(+), 1 deletion(-)
>> 
>> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
>> index efb09de4343d..b173c36bcab3 100644
>> --- a/fs/ocfs2/file.c
>> +++ b/fs/ocfs2/file.c
>> @@ -2100,14 +2100,20 @@ static long ocfs2_fallocate(struct file *file,
int mode, loff_t offset,
>>  	struct ocfs2_space_resv sr;
>>  	int change_size = 1;
>>  	int cmd = OCFS2_IOC_RESVSP64;
>> +	int ret = 0;
>>  
>>  	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
>>  		return -EOPNOTSUPP;
>
> This means we only support keep-size and pouch_hole.
> And it seems pouch_hole will also imply keep-size.
I think you're forgetting about mode = 0, which is also valid.  And the
default '0' will allow size to be changed.
>>  	if (!ocfs2_writes_unwritten_extents(osb))
>>  		return -EOPNOTSUPP;
>>  
>> -	if (mode & FALLOC_FL_KEEP_SIZE)
>> +	if (mode & FALLOC_FL_KEEP_SIZE) {
>>  		change_size = 0;
>> +	} else {
>
> Seems this will be a dead branch?
Again, you need to consider '0' as a valid mode value.  If you run
generic/228 without this patch you'll see that test failing because it
*does* hit this branch.

Cheers,
-- 
Lu?s
>
> Thanks,
> Joseph
>
>> +		ret = inode_newsize_ok(inode, offset + len);
>> +		if (ret)
>> +			return ret;
>> +	}
>>  
>>  	if (mode & FALLOC_FL_PUNCH_HOLE)
>>  		cmd = OCFS2_IOC_UNRESVSP64;

On 5/31/23 4:29 PM, Lu?s Henriques wrote:
> Joseph Qi <joseph.qi at linux.alibaba.com> writes:
> 
>> On 5/29/23 11:26 PM, Lu?s Henriques wrote:
>>> When changing a file size with fallocate() the new size isn't
being
>>> checked.  In particular, the FSIZE ulimit isn't being checked,
which makes
>>> fstest generic/228 fail.  Simply adding a call to
inode_newsize_ok() fixes
>>> this issue.
>>>
>>> Signed-off-by: Lu?s Henriques <lhenriques at suse.de>
>>> ---
>>>  fs/ocfs2/file.c | 8 +++++++-
>>>  1 file changed, 7 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
>>> index efb09de4343d..b173c36bcab3 100644
>>> --- a/fs/ocfs2/file.c
>>> +++ b/fs/ocfs2/file.c
>>> @@ -2100,14 +2100,20 @@ static long ocfs2_fallocate(struct file
*file, int mode, loff_t offset,
>>>  	struct ocfs2_space_resv sr;
>>>  	int change_size = 1;
>>>  	int cmd = OCFS2_IOC_RESVSP64;
>>> +	int ret = 0;
>>>  
>>>  	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
>>>  		return -EOPNOTSUPP;
>>
>> This means we only support keep-size and pouch_hole.
>> And it seems pouch_hole will also imply keep-size.
> 
> I think you're forgetting about mode = 0, which is also valid.  And the
> default '0' will allow size to be changed.
> 
Oops... You are right.
>>>  	if (!ocfs2_writes_unwritten_extents(osb))
>>>  		return -EOPNOTSUPP;
>>>  
>>> -	if (mode & FALLOC_FL_KEEP_SIZE)
>>> +	if (mode & FALLOC_FL_KEEP_SIZE) {
>>>  		change_size = 0;
>>> +	} else {
>>
>> Seems this will be a dead branch?
> 
> Again, you need to consider '0' as a valid mode value.  If you run
> generic/228 without this patch you'll see that test failing because it
> *does* hit this branch.
> 
> Cheers,