[netCDF #UBS-599337]: Abort on reading damaged HDF5 file

Hello,

This is something we can look at, absolutely; I'll need to review the code in 
question to see if there's a reason why it's being handled the way it is, but 
it might make more sense to return an error instead.

Thanks for reporting this, we'll take a look.

Have a great day!

-Ward

> Full Name: Ruurd Dorsman
> Email Address: address@hidden
> Organization: VORtech
> Package Version: 4.4.1.1
> Operating System: Linux, Windows
> Hardware:
> Description of problem:
> 
> Dear Sir/Madam,
> 
> We are currently trying to build an application that robustly reads data
> from netCDF files (in HDF5 file format). Because it is essential for
> our application that it continues on errors, we have written extensive
> tests. One of the tests we perform is trying to read a valid netCDF
> file of which we have changed the first byte to 0x00 to mimic file
> corruption. This causes the program to abort with an assertion error.
> 
> As far as I can tell, the error is triggered by line 2866 of nc4file.c
> because the variable hdf_file is zero. This variable is set in the same
> file on line 294 because the function H5Fis_hdf5 recognizes the file is
> not valid HDF5 and the fallback (checking the first 4 bytes of the file
> for a known file format) also produces no result.
> 
> The assertion is followed by a comment that the assert(0) should
> never happen, but apparently it can sometimes occur in rare
> circumstances. Replacing the line with something like:
> 
> return NC_ENOTNC;
> should fix the problem.
> 
> Is this fix something you would be willing to include in the next release
> of netCDF?
> 
> Kind regards,
> Ruurd Dorsman
> 
> 


Ticket Details
===================
Ticket ID: UBS-599337
Department: Support netCDF
Priority: Normal
Status: Closed
===================
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