[opensource-dev] Review Request: STORM-1118 Viewer crashes when user tries to upload image without JFIF header

[Kiptic Horsley]

> On April 8, 2011, 4:51 p.m., Boroondas Gupte wrote:
> > indra/llimage/llimagedimensionsinfo.cpp, lines 217-219
> > <http://codereview.secondlife.com/r/255/diff/2/?file=1426#file1426line217>
> >
> >     Wouldn't a seek be a "cheaper" way to determine size than reading into an actual buffer? (According to indra/llcommon/llapr.h, it returns -1 on failure.)
> >     
> >     There's also a static method LLAPRFile::size, but that seems to operate on not-yet-opened files given by filename.
> 
> Vadim ProductEngine wrote:
>     seek() may go beyond the file end, so we can't use it to check whether the file contains the needed header.
>     Well, we could seek to the end of file, but accessing the whole file just to find out that it's of wrong type looks like overkill.
>     I agree that reading into a dynamically allocated buffer doesn't look nice, but I think we can live with it as long as we only read small chunks this way.
> 
> Boroondas Gupte wrote:
>     There's no pointer equivalent of /dev/null that could be used here instead of an actual buffer, is there?
> 
> Vadim ProductEngine wrote:
>     No. Well, there is NULL, but you'll get a crash if you use it as a buffer address. :-)

The LLAPRFile::seek() with offset < 0 does apr_file_seek(file_handle, APR_END, 0), and apr_file_seek() doesn't "access the whole file" it just does an apr_file_info_get(), checks the size (the OS should know...) and jumps there, then returns the result.

So you should really do a seek() :)


- Kiptic


-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
http://codereview.secondlife.com/r/255/#review580
-----------------------------------------------------------


On April 7, 2011, 4:20 p.m., Vadim ProductEngine wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> http://codereview.secondlife.com/r/255/
> -----------------------------------------------------------
> 
> (Updated April 7, 2011, 4:20 p.m.)
> 
> 
> Review request for Viewer.
> 
> 
> Summary
> -------
> 
> * Added checks for image file contents not matching the file extension (e.g. a bitmap named file.jpg).
> * Added checks for abnormally short files to avoid crashes when parsing them.
> 
> 
> This addresses bug STORM-1118.
>     http://jira.secondlife.com/browse/STORM-1118
> 
> 
> Diffs
> -----
> 
>   indra/llimage/llimagedimensionsinfo.h 33ca961b0870 
>   indra/llimage/llimagedimensionsinfo.cpp 33ca961b0870 
> 
> Diff: http://codereview.secondlife.com/r/255/diff
> 
> 
> Testing
> -------
> 
> 
> Thanks,
> 
> Vadim
> 
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.secondlife.com/pipermail/opensource-dev/attachments/20110415/9faa177f/attachment.htm