[Mesa-dev] [PATCH] aux/pipe_loader: Don't leak error string on dlopen failure

[Ilia Mirkin]

On Fri, Nov 14, 2014 at 1:31 PM, Aaron Watry <awatry at gmail.com> wrote:
> On Fri, Nov 14, 2014 at 12:04 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
>> On Fri, Nov 14, 2014 at 12:48 PM, Aaron Watry <awatry at gmail.com> wrote:
>>> Signed-off-by: Aaron Watry <awatry at gmail.com>
>>> CC: Ilia Mirkin <imirkin at alum.mit.edu>
>>>
>>> v4: Call dlerror() twice instead of freeing glibc's memory.
>>>     Prevents issues on C Libraries that don't malloc the error string.
>>> v3: Switch comment to C-Style
>>> v2: Use strdup instead of calloc/strcpy
>>> ---
>>>  src/gallium/auxiliary/pipe-loader/pipe_loader.c | 6 ++++++
>>>  1 file changed, 6 insertions(+)
>>>
>>> diff --git a/src/gallium/auxiliary/pipe-loader/pipe_loader.c b/src/gallium/auxiliary/pipe-loader/pipe_loader.c
>>> index 8e79f85..f103497 100644
>>> --- a/src/gallium/auxiliary/pipe-loader/pipe_loader.c
>>> +++ b/src/gallium/auxiliary/pipe-loader/pipe_loader.c
>>> @@ -25,6 +25,8 @@
>>>   *
>>>   **************************************************************************/
>>>
>>> +#include <dlfcn.h>
>>> +
>>>  #include "pipe_loader_priv.h"
>>>
>>>  #include "util/u_inlines.h"
>>> @@ -101,6 +103,10 @@ pipe_loader_find_module(struct pipe_loader_device *dev,
>>>           if (lib) {
>>>              return lib;
>>>           }
>>> +
>>> +         /* Retrieve the dlerror() str twice. Once to populate the error, twice to clear it. */
>>> +        dlerror();
>>> +        dlerror();
>>
>> Is this portable? Perhaps just if PIPE_OS_UNIX or something? (For the
>> include as well...)
>>
>> I could be wrong on that though. But please check :)
>>
>
> How about changing dlerror to util_dl_error? It takes care of the
> os-portability issues.

Even better.