wine 0.9.6 segfaults (was :Re: wine 0.9.5 - segmentation fault with some apps)

[penna at bb.com.br]

Alex,

> That might be a problem. It would be better if you could compile the 
> latest snapshot, or even better, the latest CVS, from scratch. This 
> would enable you to test any patches I (or somebody else) might send to 
> try and fix the problem.

OK, I will do it then!
But I will have to learn a bit on how to use subversion trhough our 
autenticated squid proxy. 
It will take some hours (or days 8-/).
As soon as I get a local snapshot working I will post a message again 
(also after reporting the bug)

>
>>I also noticed I can do something like:
>>       WINEDUBUG=+all winebdg user.exe
>>
>>Are you interested in the output of the above? Winedbg does not 
segfault. 
>>It freezes.
>>
>> 
>>
>It should be WINEDEBUG=+all, not WINEDUBUG... might be the problem.

Sorry! Just a typo .... I meant WINEDEBUG ....

> However, the debug trace was useful by itself.
>
>The last lines of your trace show the following:
>
>0009:Call ntdll.RtlImageNtHeader(00000000) ret=7fce61da
>0009: *killed* exit_code=0
>
>This is bad - RtlImageNtHeader should be supplied a non-NULL pointer, 
>and somebody passed it a NULL one instead. In addition, it seems there 
>is an issue with the exception handling in RtlImageNtHeader
>
> From dlls/ntdll/loader.c:
>
>/***********************************************************************
> *           RtlImageNtHeader   (NTDLL.@)
>*/
>PIMAGE_NT_HEADERS WINAPI RtlImageNtHeader(HMODULE hModule)
>{
>    IMAGE_NT_HEADERS *ret;
>
>    __TRY
>    {
>        IMAGE_DOS_HEADER *dos = (IMAGE_DOS_HEADER *)hModule;
>
>        ret = NULL;
>        if (dos->e_magic == IMAGE_DOS_SIGNATURE)
>        {
>            ret = (IMAGE_NT_HEADERS *)((char *)dos + dos->e_lfanew);
>            if (ret->Signature != IMAGE_NT_SIGNATURE) ret = NULL;
>        }
>    }
>    __EXCEPT_PAGE_FAULT
>    {
>        return NULL;
>    }
>    __ENDTRY
>    return ret;
>}
>
>The exception handler is supposed to return NULL in case of a page fault 
>(such as trying to access a NULL pointer, as is your case). However, I 
>think I saw a discussion somewhere in wine-devel that advised *not* to 
>return from inside an __EXCEPT clause of an exception handler in Wine 
>(most probably because __ENDTRY needs to run in order to clean up). If 
>this is true, then RtlImageNtHeader is violating this rule. Your 
>segmentation fault might be the expected result of a violation of the 
>return rule. Could anybody in wine-devel speak up to confirm or refute 
>this observation about exception handlers?
>
>This, of course, does not address the actual issue of passing a NULL 
>pointer to RtlImageNtHeader(). I could make a set of patches to add 
>TRACEs to all functions with uses of RtlImageNtHeader(), but you need to 
>be able to apply the patches for them to be actually of use.
>
>Alex Villacís Lasso

I will be working on setting up an environment to apply the patches. 
Just wait some time in order to me to work on some issues I would have ...

Thanks.
---------------------------------------------------------
Ulisses de Sousa Penna
Analista Consultor - Banco do Brasil
Fone: +55-61-3310-6320   Fax: +55-61-3310-6435
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